Background/Objectives: Pentacyclic Triterpenoids are increasingly studied as anti-cancer agents with many advantages comparative to synthetic chemotherapeutics. The aim of this study was to prepare liposomal and nanostructured lipid formulations including a standardized extract of silver birch (Betula pendula) outer bark (TTs) and to evaluate their potential as anti-cancer agents in vitro, using Melanoma B16-F10 and Walker carcinoma cells. Methods: Appropriate solvents were selected for an efficient TTs extraction, and original recipes were used to obtain Pegylated liposomes and nanolipid complexes with entrapped TTs, comparative to pure standards (betulinic acid and doxorubicin) in similar conditions. The composition, morphology and sizes of all nanoformulations were checked by High Performance Liquid Chromatography/Mass spectrometry, Transmission Electronic Microscopy and Diffraction Light Scattering. The entrapment efficiency and their impact on cell viability, cell cycle arrest and apoptosis by Flow Cytometry was also measured on both cancer cell lines. Conclusions: The standardized TTs showed good stability, synergistic effects of main components and superior comparative to pure betulinic acid. According to experimental data, TTs showed good entrapment in liposomal and NLC nanoformulations, both delivery systems including natural, biodegradable ingredients and enhanced bioavailability. The apoptosis and necrosis effects were more pronounced for TTs liposomal formulations in both types of cancer cells, with lower cytotoxicity comparative to Doxorubicin, and can be correlated with their increased bioavailability.

Melanin is extensively distributed in organisms and believed to be synthetized by tyrosinase (TYR), leading to aberrant coloring and skin conditions when over-produced. Loquat (Eriobotrya japonica (Thunb.) Lindl.) flowers contain large amounts of bioactive substances currently few studied on their suppressive capabilities to melanin synthesis. Its isolate product (LFP) was obtained by ethanol solution extraction and resin purification, of which the inhibitory mechanism on TYR activity was elaborated by enzyme kinetics and multi-spectroscopy determinations and the impact on related proteins’ expression in mouse melanoma B16 cells was analyzed with Western blotting. HPLC-MS analysis indicated that LFP was identified into 137 compounds, with 12 including flavonoids (quercetin, isorhamnoin, p-coumaric acid, etc.), cinnamic acid and its derivatives as well as benzene and its derivatives owning TYR inhibitory activities. LFP inhibited TYR activity in a concentration-dependent manner with its IC50 value being 2.8 mg/mL and an anti-competitive mechanism involved altering the enzyme's conformation. LFP reduced the expression of TYR, TRP1, and TRP2 in melanoma B16 cells, hence inhibiting the synthesis of melanin. Considered collectively, LFP would be a viable option for treating hyperpigmentation caused by tyrosinase, providing a theoretical basis for the value-added utilization of loquat flower resource in beauty and aging related functional products.

Resistance to Immune Checkpoint Blockade (ICB) constitutes the current limiting factor for the optimal implementation of this novel therapy that otherwise demonstrates durable responses with acceptable toxicity scores. This limitation is exacerbated by a lack of robust biomarkers. In this study, we have dissected the basal TME composition at the gene expression and cellular levels that predict response to Nivolumab and prognosis. BCR, TCR and HLA profiling were employed for further characterization of the molecular variables associated with response. The findings were validated using a single-cell RNA-seq data of metastatic melanoma patients treated with ICB and by multispectral immunofluorescence. Finally, machine learning was employed to construct a prediction algorithm that was validated across eight metastatic melanoma cohorts treated with ICB. Using this strategy, we have unmasked a major role played by basal intratumoral plasma cells expressing high levels of IGKC in efficacy. IGKC, differentially expressed in good responders, was also identified within the Top response-related BCR clonotypes, together with IGK variants. These results were validated at gene, cellular and protein levels; CD138+ Plasma-like and Plasma cells were more abundant in good responders and correlated with the same RNA-seq defined fraction. Finally, we generated a 15-genes prediction model that outperformed the current reference score in eight ICB-treated metastatic melanoma cohorts. The evidenced major contribution of basal intratumoral IGKC and plasma cells in good response and outcome in ICB in metastatic melanoma is a groundbreaking finding in the field beyond the role of T lymphocytes.

The development of using mitochondrial transplantation in medical therapy are currently discussed. According to the endosymbiotic theory, the movement of mitochondria between different cells is possible. Therefore, an idea of transferring the mitochondria purified from the cells with a limited lifespan to shorten the lifespan of immortal cancer cells was generated. Human umbilical vein endothelial cell (HUVEC) is a kind of primary cell with a limited lifespan. In the present study, the mitochondria purified from HUVEC were applied to alter the malignance of B16F10 melanoma cell. In the comparison of the basic function of mitochondria, HUVEC mitochondria exhibited a higher mitochondrial membrane potential (MMP), while the lower levels in ATP, mitochondrial DNA (mt-DNA) and mitochondrial protein (mt-protein) as compared to melanoma B16F10. After transplanted the B16F10 with HUVEC mitochondria, the migration, invasion, and the proteins involved in cancer stemness were decreased, however, the proteins involved in cell proliferation, such as cyclin D1 and cyclin E1 were increased. In addition, the levels of ATP, mt-DNA and mt-protein of B16F10 were also reduced. As for the dynamics of mitochondria, the reduced expressions of DRP1 and LC3 II revealed that transferred mitochondria can attenuate the mitophagy of B16F10. In mice, inoculated the B16F10 carrying the transplanted HUVEC mitochondria resulted in the larger size of tumor, which is corresponded to the higher levels of cyclin D1 and E1. Interestingly, the lower expressions of N-cadherin, α-SMA and MMP-9 reveled the tumor were decreased in mesenchymal characteristics. Therefore, despite the HUVEC mitochondria did not inhibit the proliferation of B16F10, the metastatic characteristic was reduced.

Plasma medicine is a new field focusing on biomedical and clinical applications of cold physical plasmas, including their anticancer effects. Cold plasmas can be applied directly or indirectly as plasma activated liquids (PAL). The effect of plasma activated cell growth medium (PAM) and plasma activated phosphate buffered saline (PAPBS) were tested using a plasma pen generating streamer corona discharge in ambient air, on different cancer cell lines (melanoma A375, glioblastoma LN229 and pancreatic cancer MiaPaCa-2) and normal cells (human dermal fibroblasts HDFa). The viability reduction and apoptosis induction were detected in all cancer cells after incubation in PAL. In melanoma cells we focused on detailed insights to the apoptotic pathways. The anticancer effects depend on the plasma treatment time or PAL concentration. The first 30 minutes of incubation in PAL were enough to start processes leading to the cell death. In fibroblasts, no apoptosis induction was observed, only PAPBS, activated for longer time, slightly decreased their viability. Anticancer effects of PAM and PAPBS on cancer cells showed selectivity compared to normal fibroblasts, depended on correctly chosen activation time and PAL concentration. This selectivity, supported by optimum ratio of hydrogen peroxide and nitrites in PAL, is very promising for potential clinical applications.

3D cell cultures have improved the evaluation of drugs for cancer therapy, due to their high similarity to solid tumors. In melanoma, autophagy appears to show a dual role depending on the progression of the disease. p62 protein has been proposed for the evaluation of autophagic flux since its expression is an indicator of the state of autophagy. Pentoxifylline (PTX) and Norcantharidin (NCTD) are drugs that have been shown to have anticancer effects in various types of cancer. In this work, B16F1 mouse melanoma cell line was used, from which two-dimensional (2D) monolayer cultures and three-dimensional (3D) organoids were carried out using the hanging drop technique. The expression of p62 was determined by western blot and immunofluorescences. Our results indicate that pentoxifylline reduces p62 expression in both types of culture. While Norcantharidin increases its expression in 3D cultures at 24 h. Therefore, these drugs could have a potential therapeutic use for the regulation of autophagy in melanoma, depending on the state of evolution of the disease.

The detection and enrichment of circulating melanoma cells is a challenge as the cells are very heterogeneous in terms of their biomechanical properties and surface markers. In addition, there is a lack of valid and reliable biomarkers that predict progress and therapeutic response. We here analyzed the elasticity of A375 melanoma cells applying force spectroscopy and a microfluidic method. To identify and eventually separate circulating tumor cells, it is crucial to precisely know their physical properties. First, we used standard AFM force spectroscopy, where the elasticity of the cells is calculated from indentation with a pyramidal tip. To extend the limits of measurement with a tip, we then used cantilevers without a tip to press on the cells over a large area. The resulting Young’s moduli are slightly lower and vary less without tip presumably because of the inhomogeneity of the cells. Finally, we implemented our microfluidic method. We measured single cell elasticity by analyzing its deformation in high-speed micrographs while passing a stenosis. Combining the force field and the change in shape provides the basis for a stress strain diagram. The results from microfluidic deformation analysis were in accordance with the results from force spectroscopy. The microfluidic method provides advantages over conventional methods, since it is less invasive and less likely to harm the cell during the measurement, and the whole cell is measured as one entity without contact to a stiff substrate, while force spectroscopy is limited to the contact area of the tip, and in some cases dependent of the cell substrate interaction. Consequently, microfluidic deformation analysis allows to predict the overall elastic behavior of the whole inhomogeneous cell in three-dimensional force fields. This method may contribute to improve the detection of circulation melanoma cells in the clinical practice.

Ferruginol is a promising abietane-type antitumor diterpene able to induce apoptosis in SK-Mel-28 human malignant melanoma. We here aim to increase this activity by testing the effect of a small library of ferruginol analogues. After an screening of their antiproliferative activity (SRB staining) on SK-Mel-28 cells the analogue 18-aminoferruginol (GI50=10 µM) was further selected for mechanistic studies including effects on mitochondrial viability (MTT assay, IC50=10 µM p<0.0001), induction of apoptosis (DAPI staining, p<0.001), changes in cell morphology associated with the treatment (cell shrinkage and membrane blebbing), induction of caspase-3/7 activity (2.5x at 48h, 6.5x at 72h; p<0.0001), changes in the mitochondrial membrane potential (not significant), and effects on 2D cell migration and 3D cell invasion (modified Boyden assay, not significant). The results were compared to those of the parent molecule (ferruginol, GI50»50 µM) and paclitaxel (GI50=10 nM) as a reference drug. In conclusion, we demonstrate here that derivatization of ferruginol into 18-aminoferruginol increases its antiproliferative activity 5 times in SK-MEL-28 cells as well as changing the apoptotic mechanism of its parent molecule ferruginol from activation of caspases without depolarization of mitochondrial membrane.

Melanoma is a type of highly malignant and metastatic skin cancer. In situ molecular imaging of endogenous levels of the melanoma biomarker tyrosinase (TYR) may decrease the likelihood of mortality. In this study we proposed the weakly fluorescent probe 1-(4-(2-(4-(dicyanomethylene)-4H-chromen-2-yl)vinyl)phenyl)-3-(4-hydroxybenzyl)urea (DCM-HBU), which releases a strong red-shifted fluorescent signal after a TYR-mediated oxidation followed by hydrolysis of the urea linkage. The large Stokes shift of the dye is owed to the recovery of the intramolecular charge transfer (ICT) effect. The resulting probe derivate shows a highly ratiometric fluorescence output. Furthermore, the simultaneous excitation by two near-infrared (NIR) photons of the released DCM-NH2 fluorophore could avoid the usual drawbacks, such as cellular absorption, autofluorescence and light scattering, due to an usually short wavelength of the excitation light on biological systems, resulting in images with deeper tissue penetration. In addition, the probe is useful for the quantitative sensing of TYR activity in vivo, as demonstrated in zebrafish larvae. This new ratiometric two photon NIR fluorescent probe is expected to be useful for the accurate detection of TYR in complex biosystems at greater depths than other one-photon excited fluorescent probes.

This study aimed to investigate the potential of Cord Blood Stem Cell-derived exosome vesicles (CBSC-EVs) in regulating cancer growth and preventing cellular damage. The study aimed to examine the effects of CBSC-EVs on CHL1 cancer cells and healthy fibroblasts. The study results reveal that CBSC-EVs have an anti-cancer/antioxidant effect on CHL1 cancer cells without inducing any toxic effects on healthy lymphocytes. Further analysis of CBSC-EVs revealed the presence of seven miRNAs (noncoding RNA molecules), including three from the Let 7 family, two from the Let 5 family, and two novel miRNAs. The function of the novel miRNAs was the main focus of the study. To assess the efficacy of CBSC-EVs, CHL1 cells (a type of malignant melanoma cell line) and human fibroblasts were grouped into different treatments. One group of those cell lines were treated with CBSC-EVs, and in the second group, the cells were transfected with either miRNA inhibitor Novel 1 (miRNA IN1) plus CBSC-EVs or miRNA inhibitor Novel 2 (miRNA IN2) and CBSC-EVs to knock down those novel miRNAs in the CBSC-EVs. Therefore, by comparing these groups, the function of novel miRNAs is more understandable. In this study, the Comet assay was employed to evaluate cancer cells' DNA damage and CCK8 to measure cell viability. The findings revealed that CBSC-EVs caused an increase in DNA damage in CHL1 cells compared to cells without treatment (p

In Caucasians, basal cell carcinoma, a type of non-melanoma skin cancer, is most often found on the nose. This presents challenges for surgeons due to anatomical, functional, and aesthetic concerns. The study aimed to evaluate the distribution of tumor localization, size, morphological subtypes, surgical outcomes, radicality levels, and their correlation with recurrence rates. The research utilized data from the Hygiene Institute Health Information Centre. A retrospective analysis encompassed 343 cases of nasal skin cancer over a four-year period from January 1, 2019, to December 31, 2022. The research cohort comprised 252 female and 91 male participants, averaging 75,2 years old. Tumors were most found on the left sidewall of the nose (25.4%) and the dorsum (24.8%). The infiltrative morphological subtype was predominant (70.8%). Standard surgical excision with fasciocutaneous plastic was the preferred surgical procedure. Radical excision was achieved in 79.0% of lesions, while 16.9% were incompletely excised. Non-radically excised tumors exhibited a significantly higher recurrence rate (24.1%) compared to those with radical excision (6.3%). In nasal reconstruction, diverse surgical techniques are essential for precise adaptation based on factors like tumor characteristics and patient needs. Despite surgeons' careful adherence to excision guidelines, the potential for non-radical procedures cannot be entirely eliminated.

Non-melanoma skin cancers (NMSCs), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), are highly prevalent and a significant cause of morbidity. Image-guided su-perficial radiation therapy (IGSRT) uses integrated high-resolution dermal ultrasound to improve lesion visualization, but it is unknown whether efficacy varies by histology. This large retro-spective cohort study was conducted to determine the effect of tumor histology on freedom from recurrence in 20,069 biopsy-proven NMSC lesions treated with IGSRT, including 9,928 BCC (49.5%), 5,294 SCC (26.4%), 4,648 SCCIS (23.2%), and 199 lesions with ≥2 NMSCs (1.0%). Freedom from recurrence at 2, 4, and 6 years was 99.60%, 99.45%, and 99.45% in BCC; 99.58%, 99.49%, and 99.49% in SCC; and 99.96%, 99.80%, and 99.80% in SCCIS. Freedom from recurrence at 2, 4, and 6 years following IGSRT did not differ significantly comparing BCC vs. non-BCC or SCC vs. non-SCC but were slightly lower among SCCIS vs. non-SCCIS (p = 0.002). There were no significant differences in freedom from recurrence when stratifying lesions by histologic subtype. This study demonstrates that there is no significant effect of histology on freedom from recurrence in IGSRT-treated NMSC except in SSCIS. These findings support IGSRT as a first-line therapeutic option for NMSC regardless of histology.

Cutaneous melanoma (CM) patients respond better to immune checkpoint inhibitors (ICI) than mucosal and uveal melanoma patients (MM/UM). Aiming to explore these differences and understand the distinct response to ICI, we evaluated the serum metabolome of advanced CM, MM, and UM patients. Levels of 115 metabolites were analyzed in samples collected before ICI, using a targeted metabolomics platform. In our analysis, molecules involved in the tryptophan-kynurenine axis distinguished UM/MM from CM. UM/MM patients had higher levels of 3-hydroxykynurenine (3-HKyn), whilst patients with CM were found to have higher levels of kynurenic acid (KA). The KA/3-HKyn ratio was significantly higher in CM versus the other subtypes. UM, the most ICI-resistant subtype, was also associated with higher levels of sphingomyelin-d18:1/22:1 and the polyamine spermine (SPM). Overall survival was prolonged in patients with lower SPM levels. Our study revealed distinct metabolomic profile between the most resistant melanoma subtypes, UM and MM, compared to CM. Alterations within the kynurenine pathway, polyamine metabolism and sphingolipid metabolic pathway may contribute to the poor response to ICI. Understanding the different metabolomic profiles introduces opportunities for novel therapies with potential synergic activity to ICI, to improve responses of UM/MM.

Maslinic acid (MA) is a natural triterpene from Olea europaea whose pharmacological functions have been showed. The objective of this study was to examine MA effect on cell viability (by MTT assay), reactive oxygen species (ROS levels, by flow cytometry) and key anti-oxidant enzyme activities (by spectrophotometry) in murine skin melanoma (B16F10) cells compared to healthy cells (A10). MA induced cytotoxic effects in cancer cells (IC50 42 µM) whereas no effect was found in A10 cells treated with MA (up to 210 µM). In order to produce a stress situation in cells, 0.15 mM of H2O2 were added. Under stressful conditions, MA protected both cell lines against oxidative damage, decreasing intracellular ROS, being higher in B16F10 than in A10 cells. The treatment with H2O2 and without MA produced different responses in anti-oxidant enzymes activities depending on cell line. In A10 cells, all enzymes were up-regulated, but in B16F10 cells only superoxide dismutase, glutathione S-transferase and glutathione peroxidase increased their activities. MA restored the enzyme activities to similar levels than control group in both cell lines, highlighting that in A10 cells the highest MA doses induced values lower than control. Overall, these findings demonstrate the great anti-oxidant capacity of MA.

Oleuropein (Ole), a secoiridoid glucoside present in Olea europaea leaves, gained the interest of many scientists thanks to its several biological properties, including the anticancer one. We verified whether Ole might potentiate cytotoxicity of conventional drugs used to treat melanoma, disclosing new potential therapeutic strategy. We tested the cytotoxic action of Ole alone or in combination with chemotherapeutics on A375 human melanoma cells. We found that Ole was able, at a dose of 500 μM, to stimulate apoptosis in melanoma cells, while at a non-toxic dose of 250 μM, it affected cell proliferation and induced the downregulation of pAKT/pS6 pathway. 250 μM Ole did not potentiate the effect of Vemurafenib (PLX4032), but it succeeded in increase the cytotoxic effect of Dacarbazine (DTIC). The mayor effect was found in the association between Ole and Everolimus (RAD001), also on PLX4032-resistant BRAF melanoma cells, possibly cooperating in the inhibition of pAKT/pS6 pathway. Of interest, an olive leaf extract enriched in equimolar Ole was more effective and able to further improve DTIC and, particularly, RAD001 efficacy on BRAF melanoma cells than Ole alone. Therefore, Ole represents a natural product able to potentiate a wide array of chemotherapeutics against BRAF melanoma cells affecting pAKT/pS6 pathway.

Background: to analyze the impact of COVID-19 pandemic on characteristics and management of uveal melanoma (UM) in National Referral Center in Poland. Materials and Methods: the retrospective analysis of 1336 patients who were newly diagnosed with UM at Department of Ophthalmology and Ophthalmic Oncology, Jagiellonian University Collegium Medicum Krakow, Poland between January 1, 2018 and December 31, 2021. The demographic and clinical data were compiled including localization, size and treatment methods of tumors. Results: In total, 728 patients with UM were included before COVID-19 pandemic in years 2018-2019 and 608 were included during COVID-19 pandemic in years 2020-2021. Fixed-base dynamics indicators for the incidence of uveal melanoma (base year 2018) in the national referral center in Poland were 80.22% and 86.81% in year 2020 and 2021, respectively. UMs were statistically significantly larger and more frequently localized anterior to the equator of the eye globe in year 2021 than in year 2018 (Chi^2 Pearson test p= 0.0001 and p= 0.0077, respectively). The rate of patients treated with enucleation increased from 15.94% in year 2018 to 26.90% in year 2021 (Chi^2 Pearson test p=0.0005). Conclusions: statistically significant differences were found in the management of uveal melanoma in National Referral Center in Poland during COVID-19 pandemic with tumors being larger, more frequently localized anterior to the equator of the eye globe and more often enucleated.

Malignant melanoma (MM) is the most fatal form of skin cancer, accounting for 90% of all skin cancer deaths. Multiple dysregulated cellular pathways are involved in MM, including the MAPK/ERK and PI3K/PTEN/AKT pathways, which can be targeted with novel targeted inhibitors. However, these blockades can be overcome through the activation of alternative pathways, leading to treatment resistance. The high immunogenicity of MM has been exploited using checkpoint inhibitors resulting in improved survival outcomes of patients with advanced MM. However, their side effect profile and prohibitive cost remain a challenge and the survival outcomes for patients with metastatic MM remain poor. Treatment resistance has been attributed to the presence of cancer stem cells (CSCs), a small subpopulation of pluripotent, highly tumorigenic cells proposed to drive cancer progression, metastasis, and treatment resistance. CSCs reside within the MM tumor microenvironment (TME) regulated by the immune system, and the paracrine renin-angiotensin system (RAS), expressed in many cancer types, including MM. This article reviews the current treatment of advanced MM with targeted therapy and immune checkpoint blockers, highlights the emergence of mRNA vaccine. It also discusses the MM TME and its relationship with CSCs, and the local immune system and the paracrine RAS. It highlights the regulation of the MAPK/ERK and PI3K/AKT/mTOR pathways by the RAS via prorenin receptor and angiotensin II receptor 1, and how this relates to the CSCs and treatment resistance. This underscores the potential multi-modal therapeutic strategy by concurrent targeting of multiple components of the TME.

Cutaneous melanoma (CM) is a candidate for screening programs, since its prognosis is excellent when diagnosed in an early disease stage. Targeted screening of those at high risk for developing CM, a cost-effective alternative to population-wide screening, requires valid procedures to identify the high-risk group. Self-assessment of the number of nevi has been suggested as a component of such procedures, but its validity has not yet been established. We analyzed the level of agreement between self-assessments and expert assessments of the number of melanocytic nevi in the area between the wrist and the shoulder of both arms based on 4548 study subjects in whom mutually blinded double counting of nevi was performed. Nevus counting followed the IARC protocol. Study subjects received written instructions, photographs, a mirror, and a “nevometer” to support self-assessment of nevi larger than 2 mm. Nevus counts were categorized based on the quintiles of the distribution into five levels defining a nevus score. Cohen’s weighted kappa-coefficient was estimated to measure the level of agreement. In the total sample, agreement between self-assessments and expert-assessments was moderate (raw agreement: 50.29%, weighted κ=0.596). Self-assessed nevus counts were higher than those determined by experts (mean differ-ence: 3.33 nevi). The level of agreement was independent of sociodemographic and cutaneous factors; however, participants’ eye color had a significant impact on the level of agreement. Our findings show that even with comprehensive guidance, only a moderate level of agreement between self-assessed and expert-assessed nevus counts can be achieved. Self-assessed nevus information does not appear to be reliable enough to be used in individual risk assessment to target screening activities.

Given the importance of peroxisome proliferator-activated receptor (PPAR)-gamma in epidermal inflammation and carcinogenesis, we analyzed transcriptomic changes observed in epidermal PPARγ deficient mice (Pparg-/-epi). Gene set enrichment analysis revealed a close association with epithelial malignancy, inflammatory cell chemotaxis and cell survival. Single cell sequencing of Pparg-/-epi mice verified changes to the stromal compartment, including increased inflammatory cell infiltrates, particularly neutrophils and an increase in fibroblasts expressing myofibroblast marker genes. A comparison of transcriptomic data from Pparg-/-epi and publicly available human and or mouse actinic keratoses (AK) and cutaneous squamous cell carcinomas (SCCs) revealed strong correlation between the datasets. Importantly, PPAR signaling was the top common inhibited canonical pathway in AK and SCC. Both AKs and SCCs also had significantly reduced PPARG expression and PPARγ activity z-scores. Smaller reductions in PPARA expression and PPARα activity and increased PPARD expression but reduced PPARδ activation were also observed. Reduced PPAR activity was also associated with reduced PPARα/RXRα activity while LPS/IL1-mediated inhibition of RXR activity was significantly activated in the tumor datasets. Notably. these changes are not observed in normal sun-exposed skin relative to non-exposed skin. Finally, Ppara and Pparg were heavily expressed in sebocytes while Ppard was highly expressed in myofibroblasts, suggesting a role for PPARδ in myofibroblast differentiation. In conclusion, these data indicate PPARγ and possibly PPARα represent key tumor suppressors by acting as master inhibitors of the inflammatory changes found in AKs and SCCs.

Skin cancer is a condition characterized by the abnormal growth of skin cells, primarily caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. Different types of skin cancer include melanoma, basal cell carcinoma, and squamous cell carcinoma. Despite the advancements in targeted therapies, there is still a need for a safer, highly efficient approach to preventing and treating cutaneous malignancies. Spices have a rich history dating back thousands of years and are renowned for their ability to enhance the flavor, taste, and color of food. Derived from various plant parts like seeds, fruits, bark, roots, or flowers, spices are important culinary ingredients. However, their value extends beyond the culinary realm. Some spices contain bioactive compounds, including phenolic compounds, which are known for their significant biological effects. These compounds have attracted attention in scientific research due to their potential health benefits, including their possible role in disease prevention and treatment, such as cancer. This review focuses on examining the potential of spice-derived phenolic compounds as preventive or therapeutic agents for managing skin cancers. By compiling and analyzing the available knowledge, this review aims to provide insights that can guide future research in identifying new anticancer phytochemicals and uncovering additional mechanisms for combating skin cancer.

Hypoxia contributes to tumor progression and metastasis, and hypoxically dysregulated RNA molecules may thus be implicated in poor outcomes. Canine oral melanoma (COM) has a par-ticularly poor prognosis, and some hypoxia-mediated miRNAs are known to exist in this cancer; however, equivalent data on hypoxically dysregulated other non-coding RNAs (ncRNAs) are lacking. Accordingly, we aimed to elucidate non-miRNA ncRNAs that may be mediated by hy-poxia, targeting primary-site and metastatic COM cell lines and clinical COM tissue samples in next generation sequencing (NGS), with subsequent qPCR validation and quantification in COM primary and metastatic cells, plasma and extracellular vesicles (EVs) for any identified ncRNA of interest. Findings suggested that a number of non-miRNA ncRNA species are hypoxically up- or downregulated in COM. We identified one ncRNA, the long ncRNA fragment EN-SCAFT00000084705.1, as a molecule of interest due to its consistent downregulation in COM tissues, hypoxically and normoxically cultured primary and metastatic cell lines, when compared to the oral tissues from healthy dogs. However, this molecule was undetectable in plasma and plasma EVs, suggesting that its expression may be tumor tissue-specific and it has little potential as a biomarker. Here, we provide evidence of hypoxic transcriptional dysregulation for ncRNAs other than miRNA in COM for the first time, and suggest that ncRNA ENSCAFT00000084705.1 is a molecule of interest for future research on the role of the transcriptome in hypoxia-mediated progression of this aggressive cancer.

Collagen has been accepted in drug delivery structures due to its biocompatible chemical, physicochemical and curative actions. The study aims to evaluate the effects of a bovine collagen hydrolysate (Clg) on the main photophysical and photodynamic properties of a new gallium (III) phthalocyanine (GaPc). The absorbance of GaPc and the conjugate GaPc-Clg showed a decrease of the intensive Q-band (681 nm) and a blue shift of the maximum (678 nm) with loss of UV-band (354 nm) for 40 mg/mL Clg. The fluorescence of GaPc was evaluated with strong emission peak at 694 nm (exc: 615 nm) which was lower for GaPc-Clg (691 nm). The quantum yield of 0.23 was obtained for GaPc which was reduced for GaPc-Clg (0.012). Photo- and dark cytotoxicity was studied by NRU-assay on pigmented melanoma cells (SH-4) and normal cell lines (BJ and HaCaT). The results suggested a slight reduction of cytotoxicity for the conjugate but almost double for the selectivity index (SI: 0.71 vs. 1.49 for HaCaT cells). The study showed that bovine collagen hydrolysate can lower the PDT activity of a powerful photosensitizer with phototherapeutic index: 819 to 360, but also minimized its dark toxicity as a positive effect in the photodynamic treatment.

Actually wide excision is recommended after the primary excision of any cutaneous melanomas. The definition of the margins of wide excision indicated by the guidelines has remained unchanged over the years, although the reported indications derived from fairly dated studies, in which melanomas tend to be thicker or in advanced stages at diagnosis. These indications may no longer be current; especially in those patients affected by in situ or thin melanoma, exposing patients to a possible overtreatment. A retrospective observational study was conducted in patients who had undergone surgery for melanoma in a single institution. In a univariate model a melanoma-positive wide excision resulted related with a worst progression free survival (PFS); but this association was not confirmed in the multivariable model. Moreover, logistic model were applied to estimate the probability to find a metastasis after wide local excision (WLE) in relation to demographic data of patients and histologic information of the melanoma. Results testified that the Breslow thickness was the only factor associated with the increase of the risk to found metastases in the WLE area. The ROC curve testified that the optimum cut-off value to differentiate patients with respect those without a tumor-positive wide excision, was a Breslow thickness of 2.31mm in women, and 2.4mm in men.

Objective: To evaluate whether primary tumor treatment provides a survival benefit in uveal melanoma by comparing patients who declined treatment (Natural History Study, NHS) with those who received treatment in the Collaborative Ocular Melanoma Study (COMS) for medium-sized choroidal melanomas. Methods: A retrospective cohort study was conducted using reverse-engineered individual-level survival data from cumulative all-cause mortality curves in the original COMS and NHS publications. Censoring patterns were estimated from numbers at risk and descriptive statistics. To ensure a conservative approach, a Bonferroni-corrected significance level of 0.017 was applied. Further, if the Cox regression hazard ratio for all-cause mortality, the unadjusted risk ratio for death at 8 years, and the 95% confidence intervals (CIs) of the Kaplan-Meier curves did not indicate a smaller survival difference for the resulting data than reported in the original studies, we iteratively adjusted the NHS cohort data by reducing the 8-year cumulative mortality by one percentage point until these criteria were met. Results: Kaplan-Meier analysis revealed significantly higher cumulative mortality in the NHS cohort compared to the COMS cohort (Log-rank P = 0.012). When restricting the analysis to the first 8 years to account for unclear censoring patterns beyond this period, the NHS cohort still demonstrated worse survival (P = 0.008). Sensitivity analysis varying censoring times by ±25% over 1,000 iterations confirmed worse survival in the NHS cohort in 100% of cases. Conclusions: Patients who declined primary tumor treatment had significantly worse survival than those who received treatment. These findings support the hypothesis that primary tumor treatment confers a survival benefit in uveal melanoma.

In this study, we analyzed the microbial community of traditional fermented foods in Jeju Island to identify the distribution of useful microorganisms and confirm their anti-inflammatory and anti-melanogenic effects to determine their potential use as cosmetic ingredients. Firstly, we examined the microbial communities of Omphalius rusticus Jeotgal (OR), Spratelloides gracilis Jeotgal (SG), Chromis notata Jeotgal (CN), Turbo cornutus Jeotgal (TC), Trichiurus lepturus intestine Jeotgal (TL), Branchiostegus japonicus Sweet Rice Punch (BJ), Salted Anchovy Sauce (SA), Jeju Soy Sauce (JSS), and Jeju Soybean Paste (JSP). We found that Latilactobacillus sakei (87.2%), Tetragenococcus halophilus (37.7%), T. halophilus (96.8%), Bacillus subtilis (23.4%), T. halophilus (71.3%), L. sakei (53.7%), Lentibacillus sp. (42.9%), Enterococcus durans (14.6%), and E. durans (32.8%) were the dominant species. Secondly, to study the nine Jeju fermented foods’ anti-inflammatory and anti-melanogenic effects, we employed RAW 264.7 and B16F10 cells, classic cell models for inflammation and melanogenesis studies. Ethyl acetate extracts of the nine Jeju fermented foods all inhibited nitric oxide (NO) and melanin production in a concentration-dependent manner. Thirdly, to test the applicability of the nine Jeju fermented foods to human skin, we used the MTT assay to assess their cytotoxic effects on human keratinocytes (HaCaT cells). Finally, the topical applicability of the nine Jeju fermented foods was tested through primary skin irritation, and it was found that they did not cause any adverse effects. Therefore, extracts from the nine Jeju fermented foods have potential applications as ingredients in anti-inflammatory and anti-melanogenic products and can be used in the cosmetic industry.

Background/Objective: In this study, for the first time, we examined and compared the sensitivity of four patient-derived cutaneous melanoma cell lines to alpha radiation in vitro and analyzed it in view of cell nucleus area and the formation of double strand breaks (DSB). Melanoma cells sensitivity to alpha radiation was compared to photon radiation effects. Furthermore, we compared the sensitivity of the melanoma cells to squamous cell carcinoma. Methods: Human melanoma cell lines YDFR.C, DP.C, M12.C and M16.C, and the squamous cell carcinoma cell line, CAL 27, were irradiated in-vitro using Americium-241 as alpha-particle source. Cells were irradiated with doses of 0 to 2.8 gray (Gy). Cell viability, DNA DSB and nuclear size were measured. Results: 1. Alpha radiation caused death and proliferation arrest of all four melanoma cell lines, but inter-tumor heterogeneity was observed. 2. The most sensitive cell line (DP.C) had a significantly larger nucleus area (408 mM²) and the highest mean number of DSB per cell (9.61) compared to more resistant cells. 3. The most resistant cell, M16.C, had a much lower nucleus area (236.99 mM²) and DSB per cell (6.9). 4. Alpha radiation was more lethal than photon radiation for all melanoma cells. 5. The SCC cell, CAL 27, was more sensitive to alpha radiation than all melanoma cells, yet, had a similar number of DSB (6.67) and nucleus size (175.49 mM²) as the more resistant cells. 6. The cytotoxic effect of alpha radiation was not affected by proliferation arrest after serum starvation. 7. Killing of cells by alpha radiation was marginally elevated by ATR or topoisomerase 1 inhibition. Conclusions: This study demonstrates that various human melanoma cells can be killed by alpha radiation but exhibit variance in sensitivity to alpha radiation. Alpha radiation applied using Intra-tumoral Diffusing alpha-emitters Radiation Therapy (Alpha DaRT) methodology may serve as an efficient treatment for human melanoma.

Healthy human subjects develop spontaneous CD8+ T cell responses to melanocyte antigens (MA) expressed by normal melanocytes, such as Tyrosinase, MAGE-A3, Melan/Mart-1, gp100, and NY-ESO-1. This natural autoimmunity directed against melanocytes might confer protection against the development of malignant melanoma (MM), where MA are present as overexpressed tumor-associated antigens. Consistent with this notion we report here that functional T cell reactivity to MA was found to be diminished in untreated MM patients: while 57.5% of healthy controls (n=40) exhibited high-frequency MA-specific T cell reactivity ex vivo, such was detected in only 12% of the untreated MM patients (n=24). Three lines of evidence suggest that the MA-reactive T cells present in healthy subjects undergo exhaustion once MM establishes itself. First, only the MA-specific T cell reactivity was affected in the MM patients; that to third party recall antigens was not. Second, in these patients, the residual MA-specific T cells, unlike third party antigen reactive T cells, were functionally impaired, showing a diminished per cell IFN-γ productivity. Third, successful immunotherapy with AGI-101H melanoma vaccine restored natural CD8+ T cell autoimmunity to MA in 85% of the vaccinated patients (n= 27). The role of natural T cell autoimmunity to tumor-associated MA is discussed based on discrete levels of T cell activation thresholds.

Malignant melanoma is a lethal skin cancer containing melanoma-initiating cells (MIC), implicated in tumorigenesis, invasion, and drug resistance, and characterized by elevated expression of stem cell markers, such as CD133. We previously showed that siRNA knockdown of CD133 enhances apoptosis induced by the MEK inhibitor trametinib in melanoma cells. The current study investigates underlying mechanisms of CD133’s anti-apoptotic activity in patient-derived BAKP and POT cells, harboring difficult-to-treat NRASQ61K and NRASQ61R drivers, after CRISPR-Cas9 CD133 knockdown or Dox-inducible expression of CD133. To maintain stable expression of CD133, MACS-sorted CD133(+) positive cells were expanded by ROCK-mediated conditional reprogramming of BAKP melanoma cells (BAKR). BAKR showed increased survival via reduced apoptosis after exposure to trametinib or DTIC, compared to BAKP. CRISPR-Cas9- mediated CD133 knockdown in BAKR cells (BAKR-T3) re-sensitized the cells, while CRISPR-Cas9 knockdown of CD133 in parental BAKP and POT cells even further increased trametinib-induced apoptosis (cleaved PARP) by reducing levels of anti-apoptotic BCL-xL, p-AKT, and p-BAD, and increasing pro-apoptotic BAD and active BAX. Dox-induced CD133 overexpression had the opposite effect, and blocked trametinib-induced apoptosis in both cell lines, coincident with elevated p-AKT, p-BAD, BCL-2 and BCL-xL and decreased levels of the active form of BAX and caspases-3 and -9. The roles of CD133 in AKT and BAD phosphorylation, or in the upregulation of anti-apoptotic BCL-2 family members, was further investigated by AKT knockout with siRNA, or inhibition of BCL-2 family members with navitoclax (ABT-263). Similar to CD133 knockdown, AKT1/2 siRNA knockdown in BAKP cells also reduced p-BAD. CD133 knockdown (T3)-mediated reduction of pBAD levels was equivalent in AKT-knockdown or AKT control cells indicating that CD133 may be upstream of AKT signaling. In BAKP cells treated with trametinib and/or ABT-263, effects of ABT-263 mirrored CD133 knockdown, since levels of active BAX and cleaved-PARP in BAKP-SC (CD133-) cells increased to the same level as that exhibited by BAKP-T3 cells (CD133+). CD133 may therefore activate a survival pathway where 1) increased phosphorylation of AKT induces 2) phosphorylation and inactivation of BAD, 3) decrease in the active form of BAX, and 4) reduction in caspase-mediated PARP cleavage, indicating apoptosis suppression leading to drug resistance in melanomas. Targeting survival pathways by which CD133 may confer chemoresistance in MICs can contribute to development of more effective treatments for patients with high-risk melanoma.

Background: Sarcoma may show similarities to malignant melanoma in terms of morphologic and immunohistochemical aspects, hence making it difficult to differentiate between these two neoplasms during the diagnostic process. This systematic review aims to summarize available evidence on cases of sarcoma that were initially diagnosed as melanoma. Methods: A comprehensive search was conducted including MEDLINE/Pubmed, EMBASE and SCOPUS through March 2023. We included case series and case reports of sarcoma patients that were initially diagnosed as malignant melanoma. PRISMA guidelines were followed. Results: Twenty-three case reports and four case series with a total of 34 patients were included. The clinical presentation was heterogeneous, and the most involved anatomical regions were lower limbs (24%), head/neck (24%) and upper limbs (21%). IHC positivity was reported for S100 (69%), HMB45 (63%), MelanA (31%) and MiTF (3%). The main reasons for second assessment were unusual presentation (48%) and uncertain diagnosis (28%). EWSR1 translocation was investigated in 17/34 patients (50%) and found positive in 16/17 (94%). The final diagnosis was clear cell sarcoma (50%) or other soft tissue sarcomas (50%). Conclusions: Melanoma and some histotypes of sarcoma share many similarities. In case of atypical lesions, a second diagnosis should be considered, and ESWR1 translocation should be investigated.

Metastatic melanoma patients have a poor prognosis with poor responsiveness to chemotherapy. BRAF V600E mutations have been detected in ~40% of melanoma patients. Vemurafenib is an oral agent licensed for patients with BRAF V600E mutation-positive inoperable and metastatic melanoma, which already presents resistance that leads to patient relapse and the serious side effects. In our study, we synthesized 5 new vemurafenib analogs, RF-86A, RF-87A, RF-94A, RF-94B and RF-96B, with structural improve-ments, in order to increase the anti-proliferative and anti-metastatic effect on human melanoma. We showed that the analogs were efficient in inducing cell death and reducing the migration of A375 cells, by inhibition of MMP-2 and MMP-9 activity, indicating that this action may be longer lasting comparing to the action of Vemurafenib.

The BRAFV600E mutation, found in approximately 50% of melanoma cases, is associated with aggressive tumor behavior and poor prognosis. This study aimed to assess its impact on immunogenic cell death (ICD), a pivotal cytotoxic process triggering anti-tumor immune responses. Through comprehensive in silico analysis of The Cancer Genome Atlas data, we explored the association between the BRAFV600E mutation, immune subtype dynamics, and tumor mutation burden (TMB). Our findings revealed that the mutation correlated with a lower TMB, indicating a reduced generation of immunogenic neoantigens. Investigation into immune subtypes reveals an exacerbation of immunosuppression mechanisms in BRAFV600E-mutated tumors. To assess the response to ICD inducers, including doxorubicin and Me-ALA-based photodynamic therapy (PDT), compared to the non-ICD inducer cisplatin, we used distinct melanoma cell lines with wild-type BRAF (SK-MEL-2) and BRAFV600E mutation (SK-MEL-28, A375). We demonstrated a differential response to PDT between the WT and BRAFV600E cell lines. Further transcriptomic analysis revealed upregulation of IFNAR1, IFNAR2, and CXCL10 genes associated with the BRAFV600E mutation, suggesting their involvement in ICD. Using a gene reporter assay, we showed that PDT robustly activated the IFN-1 pathway through cGAS-STING signaling. Collectively, our results underscore the complex interplay between the BRAFV600E mutation and immune responses, emphasizing a putative correlation between tumors carrying the mutation and their responsiveness to therapies inducing the IFN-1 pathway, such as the ICD inducer PDT, possibly mediated by the elevated expression of IFNAR1/2 receptors.

Recent advancements in mass spectrometry have significantly enhanced our understanding of complex lipid profiles, opening new avenues for oncological diagnostics. This review highlights the importance of lipidomics in the comprehension of certain metabolic pathways and its potential for the detection and characterization of various cancers, in particular melanoma. Through detailed case studies, we demonstrate how lipidomic analysis has led to significant breakthroughs in the identification and understanding of cancer types and its potential for detecting unique biomarkers that are instrumental in its diagnosis. Additionally, the review addresses the technical challenges and future perspectives of these methodologies, including their potential expansion and refinement for clinical applications. The discussion underscores the critical role of lipidomic profiling in advancing cancer diagnostics, proposing a new paradigm in how we approach this devastating disease, with particular emphasis on its application in comparative oncology.

Cancer stem cells (CSCs) have been identified in many cancer types. This study identified and characterized CSCs in head and neck metastatic malignant melanoma (HNmMM) to regional lymph nodes using induced pluripotent stem cell (iPSC) markers. Immunohistochemical (IHC) staining performed on 20 HNmMM tissue samples demonstrated expression of iPSC markers OCT4, SOX2, KLF4 and c-MYC in all samples while NANOG was expressed at low levels in two samples. Immunofluorescence (IF) staining demonstrated an OCT4+/SOX2+/KLF4+/c-MYC+ CSC subpopulation within the tumor nests (TNs) and another within the peritumoral stroma (PTS) of HNmMM tissues. IF also showed expression of NANOG by some OCT4+/SOX2+/KLF4+/c-MYC+ cells within the TNs in an HNmMM tissue sample that expressed NANOG on IHC staining. In situ hybridization (n=6) and reverse-transcription quantitative polymerase chain reaction (n=5) on the HNmMM samples confirmed expression of all five iPSC markers. Western blotting of four primary cell lines derived from four of the 20 HNmMM tissue samples showed expression of SOX2, KLF4, and c-MYC but not OCT4 and NANOG, and three of these cell lines formed tumorspheres in vitro. We demonstrate the presence of two putative CSC subpopulations within HNmMM, which may be a novel therapeutic target in the treatment of this aggressive cancer.

The sunscreen industry is achieving remarkable worldwide prominence by responding to the growing need for skin protection with fast-paced innovation. Increased consumer awareness of the harmful effects of sunlight has fueled the demand for improved photo protection. The need for broad-spectrum protection from both UVA and UVB rays has inspired scientists worldwide to research new cosmetic formulations and delivery systems. More effective sunscreen actives, emollients and novel cosmetic and functional ingredients have been regularly added to the formulator’s repertoire. Creativity in innovation has been hindered only by regulatory agencies and patent restrictions worldwide. Familiarity with the current restrictive regulations and patent law infringements has become integral to any research effort attempting to provide improved protection to individuals affected by the sun’s damaging effects. The increasing incidence of skin cancers and photo damaging effects caused by ultraviolet radiation has increased the use of sun screening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Unlike the situation in Europe where sunscreen ingredients are considered under cosmetics guidelines, the FDA is required to define sunscreens as drugs since they are advertised to prevent sunburn and, more recently, the risk of skin cancer. In the USA, the FDA has been regulating this industry since August 25, 1978, with the publication of the Advance Notice of Proposed Rulemaking. Sunscreens are considered drugs and cosmetics and therefore must be governed by the FDA-OTC monograph. With the variety of sunscreen agents used in cosmetic and UV protection products, Australia, Canada, and the European Union (EU) have also developed regulatory protocols on safe sunscreen product use. Unlike the USA though, Australia has approved 34 active sunscreen ingredients and the EU has approved 28 of these ingredients. Current FDA regulations allow labeling of sunscreen products to a maximum of 30þ, despite the many products currently available with numbers as high as 100. From a cosmetic formulation point of view, increasing the SPF number in a product is governed by simple chemical principles.

Drug resistance in melanoma is a major hindrance in cancer therapy. Growth hormone (GH) plays a pivotal role in contributing to resistance to chemotherapy. Knocking down or blocking the GH receptor has been shown to sensitize the tumor cells to chemotherapy. Extensive studies have demonstrated that exosomes, a subset of extracellular vesicles, play an important role in drug resistance by transferring key factors to sensitize cancer cells to chemotherapy. In this study, we explore how GH modulates exosomal cargoes from melanoma cells and their role in drug resistance. We treated the melanoma cells with GH, doxorubicin, and GHR antagonist, pegvisomant, and analyzed the exosomes released. Additionally, we administered these exosomes to recipient cells. The GH-treated melanoma cells released exosomes with elevated levels of ABC transporters (ABCC1 and ABCB1), N-cadherin and MMP2, enhancing drug resistance and migration in recipient cells. GHR antagonism reduced these exosomal levels, restoring drug sensitivity and attenuating migration. Overall, our findings highlight a novel role of GH in modulating exosomal cargoes that drive chemoresistance and metastasis in melanoma. This understanding provides insights to the mechanisms of GH in melanoma chemoresistance and suggests GHR antagonism as a potential therapy to overcome chemoresistance in melanoma treatment.

Melanoma, a deadly form of skin cancer, has seen improved survival rates due to advances in diagnosis and treatment, yet the need for further improvement remains critical. Tumor-associated antigens, such as PRAME (Preferentially Expressed Antigen in Melanoma), offer promising avenues for enhanced diagnostic precision, prognostic assessment, and targeted immunotherapy. PRAME, a cancer-testis antigen, is selectively expressed in various cancers, including melanoma, and plays a key role in promoting tumorigenesis through inhibition of retinoic acid signaling, epithelial-to-mesenchymal transition, and immune evasion. This review explores the diagnostic utility of PRAME in distinguishing melanoma from benign nevi, its prognostic value in aggressive melanoma subtypes, and its potential as a therapeutic target in cancer vaccines and adoptive T-cell therapies. While PRAME-targeted therapies face challenges such as tumor heterogeneity and immune suppression, ongoing research aims to overcome these barriers, offering hope for more effective melanoma treatments.

Melanoma is the most aggressive form of skin cancer. In the advanced stage of development it is resistant to currently available therapeutic modalities. Increased invasiveness and metastatic potential depend on a number of proteins involved in various signal transduction pathways. Hippo signaling plays an important role in malignant transformation. Dysfunctions of the Hippo pathway initiate the expression of tumor growth factors and is associated with tumor growth and metastasis formation. This review summarizes the recent achievements in studying the role of the Hippo pathway in melanoma pathogenesis and points to the potential specific targets for anti-melanoma therapy.

Introduction: pembrolizumab showed to increase survival in patients with metastatic melanoma, Con-sidering the numerous oncoming studies, we decided to conduct a narrative review of the latest efficacy evidence regarding the use of pembrolizumab, alone or in combination, in patients with metastatic melanoma. (2) Methods: A search was conducted on Pubmed using "pembrolizumab," and "metastatic melanoma" as keywords, considering studies from 2022 onward. (3) results: we reviewed pembroli-zumab and associations, cost-effectiveness, virus, advanced acral melanoma, long-term outcomes, re-al-life data, biomarkers, obesity, and vaccines (4) Conclusions: pembrolizumab is a fundamental op-tion in the therapy of metastatic melanoma. However, a certain group of patients do not respond and therefore new combination options need to be evaluated. In particular, the use of vaccines tailored to tumor epitopes could represent a breakthrough in the treatment of resistant forms. Further studies with larger sample numbers are needed to confirm preliminary results.

Data on the KIT mutation rate in skin melanoma in the central European region is missing. Accordingly, in a cohort of 79 double wild type (BRAF/NRAS) skin melanoma KIT mutation was assessed by Sanger sequencing of exons 9,11,13,17 and 18. In this skin melanoma cohort KIT mutation frequency was found to be 34/79 (43%) with a significantly higher rate in acrolentiginous melanoma (ALM) as compared to UV-induced common variants (20/34, 58.8% versus 14/45, 31.1%, p=0.014). Exon 11 was the most frequent mutation site (44.7%) followed by exon 9 (21.1%) equally characterizing UV-induced common histotypes and ALM tumors. KIT mutation hotspots were identified in exon 9 (c491/492), in exon 11 (c559,c572, c570), in exon 13 (c642), in exon 17 (c822) and in exon 18 (c853). The relatively high KIT mutation rate in skin melanoma in this central-European cohort justifies regular testing of this molecular target.

The interest in natural remedies in modern medicine has revealed potent disease-fighting agents, such asCUR(CUR) and nicotinamide (NIC), known for their antioxidant, anti-inflammatory, and immune-boosting properties. This study explores the antibacterial and antimelanoma potential of a CUR-NIC combination and its liposomal formulation. The antibacterial efficacy was assessed against skin infection-causing bacteria, Staphylococcus aureus, while cytotoxicity and migration assays were conducted on the melanoma B16 cancer cell line. The CUR-NIC combination (1:1) demonstrated an inhibition zone of 18±0.8 mm against S. aureus and a MIC of 31.25 µg/ml, outperforming CUR alone. Whereas Lip-CUR-NIC showed an inhibition zone of 12±0.8 mm against S. aureus and a MIC of 37.5 µg/ml. Notably, the cytotoxicity assay revealed that the CUR-NIC duo synergistically inhibited melanoma cell proliferation (CI<1). Liposomal preparations further enhanced this effect, with Lip-CUR-NIC showing a remarkably low IC50 of 8.5 ± 0.3 µM compared to CUR (IC50= 9.8 ± 2.2 µM) and NIC (IC50=135.95 ± 10.2 µM). These findings highlight the synergistic potential of CUR and NIC, especially in their liposomal form, offering a promising strategy for more effective cancer treatment.

The therapeutic management of melanoma, the most aggressive form of skin cancer, remains challenging. In the search for more effective therapeutic options, metal-based complexes are being investigated for their anticancer properties. Cisplatin was the first clinically approved plati-num-based drug and, based on its success, other metals (e.g. gold) are being used to design novel compounds. In the present work, the antimelanoma potential of a new organometallic cy-clometalated Au(III) complex [[Au(CNOxN)Cl2] (CNOxN = 2-(phenyl-(2-pyridinylmethylene)aminoxy acetic acid))] (ST004) was evaluated in vitro and in vivo. Furthermore, this new gold-based complex was associated to liposomes with the lipid composition DMPC:DOPE:DSPE-PEG (50:45:5) to overcome solubility and stability problems, as well as to promote accumulation at melanoma sites and maximize the therapeutic effect. Devel-oped liposomal formulations showed a low mean size (around 100 nm), high homogeneity (PdI100 μM). Cell cycle analysis revealed an arrest in G0/G1 phase by Free-ST004 in all cell lines. In turn, LIP-ST004 led to a G0/G1 halt in B16F10, and to an arrest in S phase in A375 and MNT-1 cells. Preliminary mechanistic studies suggest gold-based inhibition of glycerol permeation through aquaglyceroporin 3 (AQP3) in human red blood cells used as a model. The proof-of-concept of the antimelanoma properties of LIP-ST004 was obtained in subcutaneous and metastatic murine melanoma models. In the latter, results showed a significant reduction on lung metastases in animals receiving LIP-ST004, com-pared to free gold complex and DTIC. Globally, this study highlights the antimelanoma potential of a new gold-based complex.

A 68-year-old man with malignant metastatic melanoma in complete remission after Pembrolizumab treatment, developed 10 months after Pembrolizumab cessation due a grade 3 diarrhea, confusion, altered mental status, progressive memory loss, gait disturbance. He was admitted to the neurologic department and comprehensive neurological workup, brain magnetic resonance imaging, cerebral fluid analysis, EEG, blood test allowed the diagnosis of autoimmune encephalitis. The patient was treated with plasmapheresis, high dose of intravenous steroids and intravenous immunoglobulins. The patient improved and he is now well with a performance status 1. This case is interesting since the AE developed approximately 10 months after the cessation of immunotherapy, the underlying cancer was in complete remission and the AE showed a good response to the treatment done.

Non-melanoma skin cancers (NMSCs) are the leading cause of skin cancer-related morbidity and mortality. Effective strategies are needed to control NMSC occurrence and progression. Non-toxic, plant-derived extracts have been shown to exert multiple anti-cancer effects. Graviola (Annona muricata), a tropical fruit-bearing plant, has been used in traditional medicine against multiple human diseases including cancer. The current study investigated the effects of graviola leaf and stem extract (GLSE) and its solvent-extracted fractions on two human NMSC cell lines, UW-BCC1 and A431. GLSE was found to: i) dose-dependently suppress UW-BCC1 and A431 cell growth, motility, wound closure, and clonogenicity; ii) induce G₀/G₁ cell cycle arrest by downregulating cyclin/cdk factors while upregulating cdk inhibitors, and (iv) induce apoptosis as evidenced by cleavage of caspases-3, -8 and PARP. Further, GLSE suppressed levels of activated hedgehog (Hh) pathway components Smo, Gli 1/2, and Shh while inducing SuFu. GLSE also decreased the expression of pro-apoptotic protein Bax while decreasing the expression of the anti-apoptotic protein Bcl-2. We determined that these activities were concentrated in an acetogenin/alkaloid-rich dichloromethane subfraction of GLSE. Our data identify graviola extracts and their constituents as promising sources for new chemopreventive and therapeutic agent(s) to be further developed for the control of NMSCs

The keratinocyte carcinomas, basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), are the most common cancers in humans. Recently, an increasing body of literature has investigated the role of miRNAs in keratinocyte carcinoma pathogenesis, progression and their use as therapeutic agents and targets, or biomarkers. However, there is very little consistency in the literature regarding the identity of and/or role of individual miRNAs in cSCC (and to a lesser extent BCC) biology. miRNA analyses that combine clinical evidence with experimental elucidation of targets and functional impact provide far more compelling evidence than studies purely based on clinical findings or bioinformatic analyses. In this study, we review the clinical evidence associated with miRNA dysregulation in KCs assessing the quality of validation evidence provided, identify gaps, and provide recommendations for future studies based on relevant studies that investigated miRNA levels in human cSCC and BCC. Furthermore, we demonstrate how miRNAs contribute to the regulation of a diverse network of cellular functions, and that large-scale changes in tumor cell biology can be attributed to miRNA dysregulation. We highlight the need for further studies investigating the role of miRNAs as communicators between different cell types in the tumor microenvironment. Finally, we explore the clinical benefits of miRNAs as biomarkers of keratinocyte carcinoma prognosis and treatment.

Uveal melanoma (UM) poses a significant clinical challenge due to its high metastasis rate and poor prognosis. Melatonin, noted for its anti-cancer properties in various malignancies, including cutaneous melanoma, shows promise in UM treatment. This study aimed to evaluate melatonin receptor expression in primary UM and its association with UM-related mortality and prognostic factors. Immunohistochemical analysis of 47 primary UM tissues showed low expression of MTNR1A and MTNR1B receptors, with MTNR1A significantly higher in patients who succumbed to UM. Analysis of TCGA data from 80 UM patients revealed RNA expression for MTNR1A, RORα, and NQO2, but not MTNR1B or GPR50. Higher MTNR1A RNA levels were observed in patients with a BAP1 mutation, and higher NQO2 RNA levels were noted in patients with the epithelioid tumor cell type. However, Kaplan-Meier analysis did not show distinct survival probabilities based on receptor expression. The study concludes that UM clinical samples express melatonin receptors, suggesting a potential mechanism for melatonin's anti-cancer effects. Despite finding higher MTNR1A expression in patients who died of UM, no survival curve differences were observed. Further research is needed to explore additional mechanisms of melatonin’s oncostatic effects, including its antioxidant properties and immune modulation.

Purpose: Melanoma’s incidence is increasing, and elderly people could be significantly impacted since the majority occurs in people over 65 years of age. Combined targeted therapies (TT) are current standard regimen for BRAF mutated metastatic melanoma (MM). Except for subgroups of pivotal trials, little data are available for TT in this population. Materials and Methods: Outcomes were explored in real life patients from MelBase, a French multicentric biobank dedicated to the prospective follow-up of unresectable stage III or IV melanoma. Patients treated by BRAF TT and/or MEK TT combined or not, were included from 2013 to 2017 in 2 groups: group 1 <65-year-old (yo), group 2 >65 yo, analyzed for tolerance and efficacy. Results: 353 patients were included: 231 in group 1, 122 in group 2. Median follow-up was 12 months (M). Median time of treatment was 6.9 M. A total of 80% had at least one Adverse Effect (AE). Most frequent AE (all grades) were mainly skin and subcutaneous, general, and gastrointestinal disorders. A total of 31% of AE were grade 3–4: 28% in group 1 and 39% in group 2 (p = 0.05). No differences were observed in all AE grades proportion, dose modifications, interruptions, and discontinuations. For each group, median overall survival was 20.3 M (CI 95%: 15.5–27.9) and 16.3 M (CI: 14.5–26.9), respectively (p = 0.8). Median progression free survival was 7.8 M (6.4–9.9) and 7.7 M (CI: 5.8–11.3) (p = 0.4). Objective response rate was 59% and 50% (p = 0.6). Conclusion: This study on a large multicentric cohort is the first to assess that TT is well tolerated in elderly BRAF-mutated patients such as in patients younger than 65. Efficacy was similar between groups with outcomes reaching those from pivotal studies. There is thus no argument against using TT in elderly people, although an onco-geriatric opinion is welcome for the most vulnerable.

The use of circulating cell-free (cf) DNA to monitor cancer progression and response to therapy has significant potential but there is only limited data on whether this technique can detect the presence of low frequency subclones that may ultimately confer therapy resistance. In this study, we sought to evaluate whether whole-exome sequencing of cfDNA can accurately profile the mutation landscape of metastatic melanoma. We used whole-exome sequencing (WES) to identify variants in matched tumor-derived genomic (g) DNA and plasma-derived cfDNA isolated from a cohort of 10 metastatic cutaneous melanoma patients. WES parameters such as sequencing coverage and total sequencing reads were comparable between gDNA and cfDNA. There was significant concordance between gDNA and cfDNA based on the total number of variants identified and the degree of overlap in variants which was independent of the site of tumor biopsy. The mutant allele frequency of common single nucleotide variants was lower in cfDNA reflecting lower read depth and dilution of circulating tumor DNA in the circulation by other cfDNA species. In addition to known melanoma driver mutations, several other melanoma-associated mutations were found to be concordant between matched gDNA and cfDNA. This study highlights that WES of cfDNA can capture clinically-relevant mutations present in melanoma metastases, but does not appear to provide any additional unique information on tumor heterogeneity. Targeted deep sequencing may be required to detect low frequency genomic aberrations known for predicting therapy resistance.

Background and aims: Brain metastases are prevalent in the late stages of malignant melanoma. Multimodal therapy remains challenging. Patient-derived organoids (PDOs) represent a valuable pre-clinical model, faithfully recapitulating key aspects of the original tumor, including the heterogeneity and the mutational status. This study aimed to establish PDOs from melanoma brain metastases (MBM-PDOs) and to test the feasibility of using them as a model for in vitro targeted-therapy drug testing.Methods: Surgical resection samples from eight patients with melanoma brain metastases were used to establish MBM-PDOs. Samples were enzymatically dissociated followed by seeding into low-attachment plates to generate floating organoids. The MBM-PDOs were characterized genetically, histologically, immunohistologically and compared with the parental tissue. The MBM-PDO cultures were exposed to dabrafenib (BRAF inhibitor) and trametinib (MEK inhibitor) followed by cell viability assessment.Results: Seven out of eight cases were successfully cultivated, maintaining the histological, immunhistological phenotype, and the mutational status of the parental tumors. Five out of seven cases harbored BRAF V600E mutations and were responsive to BRAF and MEK inhibitors in vitro. Two out of seven cases were BRAF wild type, one case harboring an NRAS mutation and the other harboring a KIT mutation, and both were resistant to BRAF and MEK inhibitor therapy. Conclusion:We successfully established PDOs from melanoma brain metastases surgical specimens, which exhibited a consistent histological and mutational profile with the parental tissue. Using FDA-approved BRAF and MEK inhibitors, our data demonstrates the feasibility of employing MBM-PDOs for targeted-therapy in vitro testing.

Uveal melanoma represents the most prevalent form of primary malignant intraocular tumor in adults. Historically, enucleation was considered the gold-standard approach in the treatment of uveal melanoma. Nowadays, radiotherapy is the most commonly used therapy, aiming at a better quality of life. However, radiotherapy can result in several ocular complications, some of which may be vision-threatening. Radiation-induced dry eye, scleral necrosis, cataract, rubeosis iridis, neovascular glaucoma, radiation retinopathy and maculopathy and optic neuropathy are the most common. This article aims to summarize the current literature on the ocular complications after radiotherapy, their clinical features, risk factors and management strategies. A thorough understanding is crucial for ophthalmologists and oncologists to provide optimal patient care, improve visual outcomes, and minimize long-term complications.

Tailoring extracellular vesicles (EVs) as targeted drug delivery systems to enhance the therapeutic efficacy showed superior advantage over liposomal therapies. Herein, we developed a novel nanotool for targeting B16.F10 murine melanoma, based on EVs stabilized with Polyethylene glycol (PEG) and loaded with doxorubicin (DOX). Nanosized EVs were efficiently enriched from melanoma cells cultured under metabolic stress by ultrafiltration coupled with size exclusion chromatography (UF-SEC) and characterized by size, morphology, and proteome. To reduce their clearance in vivo, EVs were PEGylated and passively loaded with DOX (PEG-EV-DOX). Our data suggested that the low PEG coverage of EVs might still favor EV surface protein interactions with target proteins from intratumor cells, ensuring their use as “Trojan horses” to deliver DOX to the tumor tissue. Moreover, our results showed a superior antitumor activity of PEG-EV-DOX in B16.F10 murine melanoma models in vitro and in vivo compared to that exerted by clinically applied liposomal DOX in the same tumor model. The PEG-EV-DOX administration in vivo reduced NF-κB activation and increased BAX expression, suggesting better prognosis of EV-based therapy than liposomal DOX treatment. Collectively, our results highlight the promising potential of EVs as optimal tools for systemic delivery of DOX to solid tumors.

Skin cancer is a prevalent and heterogenous disease with several subtypes, such as melanoma, basal cell carcinoma, and squamous cell carcinoma. Among them, melanoma is the most aggressive subtype, with a higher propensity to spread compared to most solid tumors. The application of OMICS approaches has revolutionized the field of melanoma research by providing comprehensive insights into the molecular alterations and biological processes underlying melanoma development and progression. This review aims to offer an overview of melanoma biology, covering its transition from primary to malignant melanoma, as well as the key genes and pathways involved in the initiation and progression of this disease. Utilizing online databases, we extensively explored the general expression profile of genes, identified the most frequently altered genes, and gene mutations, and examined genetic alterations responsible for drug resistance. Additionally, we studied the mechanisms responsible for immune checkpoint inhibitors resistance in melanoma.

Immune checkpoint inhibitors (ICIs), including anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and anti-programmed death-1 (PD-1) antibodies, have initiated a new era in the treatment of malignant melanoma. ICIs can be used in various settings, including as first-line, adjuvant, and neoadjuvant therapy. In the scope of this review, we examined clinical studies utilizing ICIs in the context of treating oral mucosal melanoma, a rare disease albeit with an extremely poor prognosis, with a specific focus on unraveling the intricate web of resistance mechanisms. The absence of a comprehensive review focusing on ICIs in oral mucosal melanoma is notable. Therefore, this review seeks to address this deficiency by offering a novel and thorough analysis of the current status, potential resistance mechanisms, and future prospects of applying ICIs specifically to oral malignant melanoma. Clarifying and thoroughly understanding these mechanisms will facilitate the advancement of effective therapeutic approaches and enhance the prospects for patients suffering from oral mucosal melanoma.

(1) Background: better mechanistic understanding of desmosome disruption and acantholysis in Grover disease (GD) may improve management of this disease. Recent molecular studies highlighted promising pathways to be explored, by directly comparing GD and selected features of associated skin diseases. The association between GD and cutaneous keratinocyte carcinomas, the most prevalent non-melanoma skin cancers (NMSC), is not completely characterized. (2) Objective: To review the medical literature regarding GD-associated cutaneous keratinocyte cancers, focusing on molecular features, pathophysiological mechanisms and disease associations, to help guide future research and patient management. (3) Result: GD has been associated with a variety of skin conditions, but its association with skin cancers has been rarely reported. Between 1983 and 2024 only 9 scientific papers presented data supporting this association. Interestingly, we found that GD may mimic multiple NMSCs, as few authors reported GD cases misdiagnosed as multiple cutaneous squamous cell carcinomas for more than 4 years, or the presence of superficial basal cell carcinoma–like areas associated with focal acantholysis. (4) Conclusions: (a) GD may be an imitator of multiple NMSCs and (b) the relationship between GD and NMSCs may reveal promising pathways for the mechanistic understanding of desmosome disruption and acantholysis in GD and may even lead to its reclassification as a distinctive syndrome.

Cutaneous metastatic melanoma (CMM) is the most aggressive form of skin cancer with a poor prognosis. Drugs-induced secondary tumorigenesis and the emergency of drug resistance worsen the already worrying scenario, thus rendering urgent the development of new treatments, not dealing with mutable cellular processes. Triphenyl phosphonium salts (TPPSs), in addiction to act as cytoplasmic membrane disruptors, are reported to be mitochondria-targeting compounds, exerting anticancer effects mainly by damaging their membranes and causing depolarization, impairing mitochondria functions and their DNA, triggering oxidative stress (OS), and priming primarily apoptotic cell death. TPP-based bola-amphiphiles are capable to self-form nanoparticles (NPs) with enhanced biological properties, as commonly observed for nanomaterials. Already employed in several other biomedical applications, only recently the per se selective potent antibacterial effects of a TPP bola-amphiphile has been demonstrated on 50 multidrug resistant (MDR) clinical superbugs, as well as its exceptional and selective anticancer properties, on sensitive and MDR neuroblastoma cells. Here, aiming at finding new molecules possibly developable as new treatments for counteracting CMM, the effects of this TPP-based bola-amphiphile (BPPB) have been investigated against two BRAF mutants CMM cell lines (MeOV and MeTRAV) with excellent results (even IC50 = 49 nM on MeOV after 72 h treatment). Upon these findings and considered the low cytotoxicity of BPPB against different mammalian not tumoral cell lines and red blood cells (RBCs, selectivity indexes up to 299 on MeOV after 72 h treatment), the possible future development of BPPB as topical treatment for CMM lesions was presumed. In this sight, a biodegradable hyaluronic acid (HA)-based hydrogel formulation (HA-BPPB-HG) was prepared without using any potentially toxic crosslinking agents, but simply dispersing suitable amounts of the two ingredients in water and sonicating under gentle heating. HA-BPPB-HA was completely characterized with promising outcomes, such as high swelling capability, high porosity and viscous elastic rheological behavior.

The landscape of clinical management for metastatic melanoma (MM) and other solid tumors has been modernized by the advent of immune checkpoint inhibitors (ICI), including programmed cell death-1 (PD-1), programmed cell death-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors. While these agents demonstrate efficacy in suppressing tumor growth, they also lead to immune-related adverse events (irAEs), resulting in exacerbation of autoimmune diseases such as Rheumatoid arthritis (RA), Ulcerative colitis (UC), and Crohn’s disease (CD). The immune checkpoint inhibitors offer promising advancements in the treatment of melanoma and other cancers, but they also present significant challenges related to irAEs and autoimmune diseases. Ongoing research is crucial to better understand these challenges and develop strategies for mitigating adverse effects while maximizing therapeutic benefits. In this manuscript, we addressed this challenge using network-based approaches by constructing and analyzing molecular and signaling networks associated with tumor-immune cross-talk.. Our analysis revealed that IL6 is the key regulator responsible for irAEs during ICI therapies. Furthermore, we conducted an integrative network and molecular-level analysis, including virtual screening, of drug libraries, such as the Collection of Open Natural Products (COCONUT) and the Zinc15 FDA-approved library, to identify potential IL-6 inhibitors.. Subsequently, the compound amprenavir was identified as the best molecule that may disrupt essential interactions between IL6 and IL6R responsible for initiating signaling cascades underlying irAEs in ICI therapies.

Melanoma, one of the most aggressive forms of skin cancer, is also one of the most diagnosed cancer types. While surgical excision of the lesions is the primary treatment for melanoma, not all cases are candidates for surgical procedures. New treatments and complementary options are necessary, given the increasing diagnosis rate. In the present study, a norcantharidin-containing nanoemulsion was developed and evaluated in vivo using a syngeneic graft murine model. Our model contemplates an amputation surgery simulating the standard treatment and the role of the nanoemulsion as a potential adjuvant therapy. We observed a significant decrease in the growth rate of the melanoma lesion in the treated groups compared to the control group, both at the 20th and 30th days of treatment. Moreover, we evaluated the drug bioavailability in serum samples, and the results showed that norcantharidin was detectable in a range of 0.1 to 0.18 mg per mL in the treated groups. Furthermore, histopathological analysis was performed on the amputated tumors, where significant differences were found regarding size, mitosis rate, lymphocytic infiltration, and multispectral quantitative image analysis compared to the control group. The norcantharidin-containing nanoemulsion could be a potential alternative or adjuvant therapy if more clinical studies are conducted. Topical nanosystems can become or complement standard therapies, which is needed as melanoma affects not only in terms of mortality but also the patient's morbidity and life quality.

Cutaneous squamous cell carcinoma is a prevalent malignancy with a rising incidence and notably high mutational load. Exploring the genetic nuances of cSCC and investigating molecular approaches stands as a potential avenue for improving outcome in high-risk patients. This retrospective case-control study involved two cohorts of 14 patients (“discovery cohort”) and 12 patients (“validation cohort”) with cSCC located in head-neck anatomical district and diagnosed at pT2 stage. Overall, cases developed early local relapse of the disease whereas controls never re-lapsed during the entire follow-up period. Next generation sequencing (NGS) approach conducted on histological samples revealed that TP53 and CDKN2A were the most frequently mutated genes in our series. No specific mutation was identified as potential prognostic or therapeutic targets. Controls exhibited a tendency toward a higher mutational rate compared to cases. It is possible that an increased number of mutations could prompt the cSCC to expose more antigens, becoming more immunogenic and facilitating the recognition by the immune system. This could enhance and sustain immunological response, potentially preventing future recurrences.

Label-free confocal photothermal (CPT) microscopy was utilized for the first time to investigate malignancy in mouse skin cells. A laser diode (LD) with 405nm or 488nm was used as a pump and 638nm LD as a probe for the CPT microscope. The Grey Level Cooccurrence Matrix (GLCM) for texture analysis was applied to the CPT images. Nine parameters of GLCM were calculated for the intracellular super-resolved CPT images, and the parameters Entropy and Prominence were found to be most suited among the nine parameters to discriminate between healthy cells and MM cells in case pump wavelength of 488nm is used.

Cutaneous Melanoma (CM) is the most lethal form of skin cancer if it becomes metastatic, where treatment options and survival chances decrease dramatically. Immunotherapy treatments based on the immunologic checkpoint inhibitors (PD-1 and CTLA4) constituted a main breakthrough in the treatment of metastatic CM, particularly in the long-term benefit. However, several molecular pathways are responsible for the failure of this strategy in about 50-70% of CM patients. Some Long Non-coding RNAs (lncRNAs), and circular RNAs (circRNA) are implicated in triggering pro- and antitumorigenic responses to various cancer treatments. The relationship between lncRNA, circRNA and Immune Checkpoint Blockade (ICB) immunotherapy is not extensively explored in cutaneous metastatic melanoma (CMM). The aim of this study is to evaluate the potential role of both circRNA and lncRNA as a predictive immunotherapy biomarker in CMM. RNA-seq from 12 FFPE samples from the metastatic biopsy of metastatic melanoma patients treated with Nivolumab were analyzed. Our findings indicate that specific lncRNA and circRNA are involved in regulatory networks of the immune response against metastatic melanoma under treatment with nivolumab. Moreover, we have established a risk score that allows the prediction of Overall survival (OS) and Progression-free survival (PFS) of CMM patients with high accuracy. This proof of principle work provides a possible insight on the function of ceRNA, contributing to decipher the complex molecular mechanism of ICB cancer treatment response.

Background: Emerging data indicate that radiotherapy can modulate antitumour immune responses. Regulatory T cells (Tregs) are a key immunosuppressive subpopulation of interest. We aimed to evaluate the impact of conventional fractionated radiotherapy on circulating Treg levels in melanoma patients and to determine the correlation between these changes and survival. Understanding radiotherapy–immunity interactions may facilitate personalized combination therapies. Methods: Peripheral blood samples from 32 melanoma patients were analysed to quantify Tregs before and 1-3 months after regional lymph node radiotherapy using flow cytometry. Tregs were characterized as CD4+/CD25+/CD127-. Total CD4+ T cells were also evaluated. Changes were compared to those in a control group of 30 tumor-free patients. Overall survival was correlated with T-cell subset dynamics induced by radiotherapy. Results: At baseline, the median percentage of Tregs was not significantly lower in melanoma patients than in controls (7.4% vs 8.32%, p=0.17). Radiotherapy markedly increased the median Treg count to 10.01% (p=0.0008), with a concomitant increase in total CD4+ cells (to 11.71%, p=0.001), indicating systemic expansion. Patients exhibiting coordinated increases in Treg and CD4+ T cells after treatment had a significantly improved prognosis compared with nonresponders (median OS 27.8 vs 13.1 months, p=0.001). Conclusions: Our study demonstrated the significant effects of standard fractionated radiotherapy on systemic Treg levels in melanoma patients. Radiation-induced changes in T-cell subset proportions hold prognostic value. Monitoring of circulating lymphocyte subsets could facilitate personalized combination therapies.

Trend patterns of melanoma skin in Serbia from 1999 to 2020 *Rancic K. Natasa 1,2, Tiodorovic B. Danica 1,4, Ilic V. Mirko 2, Biljana N. Kocic 1,2, Maksimovic S. Natasa 3, Ilija D. Kocic 4, Dusan P. Miljkovic 4, Otasevic A. Suzana 1,2 Introduction. Melanoma of the skin represents about 1% of all skin cancers and it causes nearly 80% of skin cancer deaths. Due to its increasing incidence, particularly in the most developed countries it represents a great challenge for primary prevention. Objective. To explore patterns and analyze incidence trends of melanoma in Central Serbia from 1999 to 2020. Materials and Methods. Descriptive study was done and data were obtained from the Population-based Cancer Registry of Serbia. The joinpoint regression analysis was done to assess the incidence trend of the melanoma skin: the annual percent change (APC) along with its 95% confidence interval (95% CI) was calculated. Results. A total number of 9952 new melanoma cases were registered melanoma (5204 in males and 4748 in females) during the observed period. Males represented 52.3% of all patients, with male to female ratio of incidence 2.09:1. A non significant increasing trend of incidence in males from 1999 to 2013 with APC of 2.53% (95%CI: from -18.2 to 21.9, p=1) and significantly increasing trend from 2013 to 2020 with the APC of 11.29 % (95%CI: from 1.4 to 5.8, p<0.001) was established. An incidence trend in females has stabilized in the whole studied period, with APC of 0.42% (95%CI: from -3.3 to 6.8, p=0.1). Melanoma of the skin was not common before the age of 30. Out of all cases and about of 76% new cases were diagnosed in persons ≥ 50 years of age. Conclusion. The incidence trend of new melanoma cases significantly increase in the whole population from 1999 to 2020. The significant increasing of incidence trend in males and stabilization of incidence trend in females was established. Males had significantlly higher incidence rates than femalesand over of 76% new melanoma cases were diagnosed in persons above 50 years of age.

Melanoma is a highly aggressive type of skin cancer produced by malignant transformation of melanocytes and it is usually associated with a poor prognosis. Clinically, melanoma has several stages associated with migration and invasion of the cells through the skin layers, rapid cell spreading and formation of tumors in multiple organs. The main problem is the emergence of resistance of melanoma to the applied methods of treatment, thus it is of primary importance to find more crucial signaling pathways that control the progression of this type of cancer and could be targeted to prevent melanoma spreading. The main life-threatening stage of melanoma is metastasis formation, and 3D cell spheroids are better suited for the study of this process. Using a combinative approach (RT-PCR, immunofluorescence, patch-clamp and calcium imaging) we showed the functional expression of mechanosensitive Piezo1 channels in SK-MEL-2 aggressive melanoma cell line. We found that chemical activation of Piezo1 by its selective agonist Yoda1 completely prevents melanoma spheroid formation, and could be considered as a novel approach for the prevention of melanoma development.

MicroRNAs (miRNAs) dysregulation contribute the cancer pathogenesis. However, the miRNA profile of canine oral melanoma (COM), one of the frequent malignant melanoma in dog is still unrevealed. The aim of this study is to reveal the miRNA profile in canine oral melanoma. MicroRNAs profile of oral tissues from normal healthy dogs and COM patients were compared by next-generation sequencing. Along with tumour suppressor microRNAs (miRNAs), we report 30 oncogenic miRNAs in COM. Expression of miRNAs were further confirmed by quantitative real-time PCR (qPCR). Pathway analysis showed that deregulated miRNAs impact on cancer and signalling pathways. Three oncogenic miRNAs targets (miR-450b, 301a, and 223) from human study also were down-regulated in COM and had significant negative co-relation with their respective miRNA. Furthermore, we found that miR-450b expression is higher in metastatic cells and regulated MMP9 expression through a PAX9-BMP4-MMP9 axis. In silico analysis indicated that miR-126, miR-20b, and miR-106a regulated the highest numbers of differentially expressed transcription factors in respect to human melanoma. Chromosomal enrichment analysis revealed the X chromosome was enriched with oncogenic miRNAs. We comprehensively analyzed the miRNA’s profile in COM which will be a useful resource for developing therapeutic interventions in both species.

Background and Objectives: Multiple primary malignant tumors represent a small percentage of the total number of oncological cases and can involve either metachronous or synchronous development and represent challenges in diagnosis, staging, and treatment planning. Our purpose is to present a rare case of bladder adenocarcinoma in a female patient with multiple primary malignant tumors and to provide systematic review of the available literature. Materials and Methods:A 67-year-old female patient who was admitted altered general condition, and anuria. The past medical history of the patient included malignant melanoma (2014), cervical cancer (2017), colon cancer (2021), obstructive anuria (2023), liver metastasectomy (2023). Transurethral resection of bladder tumor was performed for bladder tumors. Results: Contrast CT highlighted multiple pulmonary metastases, a poly nodular liver con-glomerate, retroperitoneal lymph node, II/III grade left ureterohydronephrosis, and no digestive tract tumor masses. The pathological result of the bladder resection showed an infiltrative adenocarcinoma. Conclusions: The difference between primary bladder adenocarcinoma tumor and metastatic colorectal adenocarcinoma is the key for the future therapeutic strategy. Identification and assessment of risk factors such as viral infection, radiotherapy, chemotherapy, smoking, genetics are pivotal in understanding and managing multiple primary malignant tumors. Personalized prevention strategies, screening programs may facilitate the early detection of this tumors, synchronous or metachronous one. The use of multicancer early detection (MCED) blood tests for early diagnosis appears promising. However, additional research is needed to standardize these techniques for cancer detection.

In this study, we aimed to identify the features of indeterminate choroidal melanocytic lesions visualized on optical coherence tomography angiography (OCTA) and to identify predictors of growth. We retrospectively evaluated 86 patients with indeterminate lesions treated at our cen-tre from 2016 to 2021. Clinical management involved active surveillance followed by brachy-therapy if growth was detected. The lesions were classified into two groups according to wheth-er they grew (small melanomas) or remained stable (choroidal nevi). Growth was detected in 19 (22.1%) lesions. All patients underwent OCTA at baseline. These images were compared to iden-tify possible predictors of growth. Significant between-group differences were observed in thickness (p=0.00), greatest basal diameter (p=0.00), number of risk factors (p=0.00), symptoms (p=0.001; relative risk [RR]: 4.3), orange pigment (p=0.00; RR: 6.02), and ultrasonographic hol-lowness (Kappa sign); p=0.000; RR: 5.3). The melanomas had significantly more vessels with a diameter ≥ 76.3 µm (p=0.02; RR: 2.46). The time to growth in these lesions was significantly shorter (p=0.05) than in lesions with smaller vessels. These findings show that vessel diameter quantified by OCTA can differentiate between choroidal nevi and small melanomas, especially when considered together with clinical risk factors.

Melanoma is a malignant, highly metastatic neoplasm showing increasing morbidity and mortality. Tumor invasion and angiogenesis are based on remodeling of the extracellular matrix (ECM). Selective inhibition of functional components of cell-ECM interaction, such as hyaluronic acid (HA), matrix metalloproteinases (MMPs), and integrins, may inhibit tumor progression and enhance the efficacy of combination treatment with checkpoint inhibitors (ICBs), chemotherapy, or immunotherapy. In this review, we have combined the results of different approaches targeting extracellular matrix elements in melanoma in preclinical and clinical studies. The identified limitations of many approaches, including side effects, low selectivity and toxicity, indicate the need for further studies to optimize therapy. Nevertheless, significant progress in expanding our understanding of tumor biology and the development of targeted therapies holds great promise for the early approaches developed several decades ago to inhibit metastasis through ECM targeting.

This study investigates the effects of xylitol, a natural sugar alcohol, on tumor progression in syngeneic mouse cancer models. Xylitol has been known for its dental health benefits, but emerging evidence suggests broader biological roles, including potential anti-cancer properties. We explored xylitol's impact on two mouse cancer models: 4T1 mammary carcinoma and B16F10 melanoma. Xylitol's efficacy in inhibiting cancer cell lines and modulating tumor progression was assessed using immunocompetent female mice. The experiments involved intratumoral and peri-tumoral administration of a 20% xylitol solution in two mouse strains: BALB/c (4T1 mammary carcinoma) and C57BL/6 (B16F10 melanoma). Tumor volume, histopathology, and metabolomic analyses were conducted to gauge xylitol's influence. The study revealed that xylitol administration initially reduced tumor growth in the B16F10 melanoma model, accompanied by alterations in tumor metabolism. However, similar effects were not observed in the 4T1 mammary carcinoma model, and melanoma tumor growth re-commenced after stroma deterioration permitted xylitol solution leakage. These findings suggest that xylitol may have potential as an adjunct therapy in cancer treatment, specifically in melanoma. The differential response between the two cancer models underscores the complexity of cancer biology and the need for further investigation into xylitol's mechanisms of action and its role in cancer therapy.

Cytokines and chemokines (chemotactic cytokines) are soluble extracellular proteins that bind to specific receptors and play an integral role in the cell-to-cell signaling network, in addition can promote the homing of cancer cells into different organs. We investigated the potential relationship between human hepatic sinusoidal endothelial cells (HHSECs) and several melanoma cell lines for the expression of chemokine and cytokine ligand and receptor expression during invasion of melanoma cells. In order to define the invasion related gene expression differences, we selected invasive and non-invasive subpopulations of cells after co-culturing with HHSECs. In addition, we determined protein expression of the endothelial cells before and after co-culturing with melanoma cell lines originated from primary tumors. Cell lines with increased invasive capacity after culturing with conditioned medium showed a set of receptor genes (CXCR1, IL1RL1, IL1RN, IL3RA, IL8RA, IL11RA, IL15RA, IL17RC, and IL17RD) with significantly different expression. It is very important note, that the IL11RA gene expression level was also significantly increased in primary melanoma tissues with liver metastasis as well. Proteome arrays revealed 15 differentially expressed proteins (including CD31, VCAM-1, ANGPT2, CXCL8, and CCL20) in the hepatic endothelial cells after co-cultured with melanoma cells. Our findings clearly indicate the interaction between liver endothelial- and melanoma cells. Based on our data, we assume that overexpression of the IL11RA gene might has key role in the formation of organ specific metastasis to the liver by primary melanoma cells.

Malignant melanoma and urological cancers originate from different tissues and organs, yet several studies highlight connections between these malignancies, including common risk factors, genetic predispositions, and immunological pathways. Research indicates that individuals with a history of melanoma have an elevated risk of developing renal cell carcinoma (RCC), while those with RCC are more likely to develop melanoma. Shared factors such as a personal or family history of cancer, UV radiation exposure, smoking, and obesity have all been linked to an increased incidence of various cancer types. A major link between malignant melanoma and urological cancers is the presence of shared genetic mutations and familial cancer syndromes. Key mutations, including germline mutations in BRCA1, MITF, CDKN2A, TP53, and alterations in the PI3K/AKT pathway, significantly contribute to the risk of both types of malignancies. Personalized medicine, which tailors prevention and treatment strategies to an individual’s genetic, environmental, and lifestyle factors, has significantly improved cancer care. The primary aim is to select the most effective treatment for each patient, maximizing therapeutic outcomes, reducing side effects, and minimizing the risk of drug resistance. Advances in genomics and immunology are driving the development of personalized therapies that target specific molecular pathways and immune responses common to both melanoma and urological cancers. Angiogenesis inhibitors and checkpoint inhibitors have demonstrated notable success in treating these cancers, with tumor mutational burden serving as a valuable biomarker for predicting the efficacy of immune checkpoint inhibitors.

Background: Cutaneous malignant melanoma (CMM) is one of the most aggressive types of skin cancer. Currently, innovative approaches such as target therapies and immunotherapies have been introduced in clinical practice for the treatment of metastatic CMM. Data of clinical trials and real life studies that evaluate the outcomes of these therapeutic associations are necessary to establish their clinical utility. The aim of this study is to investigate the types of oncological treatments employed in the real-life clinical management of patients with advanced CMM in several Italian centers which are part of the Clinical National Melanoma Registry (CNMR), and the oncological outcomes obtained. Methods: CNMR collects data of patients with a histologically confirmed diagnosis of primary CMM treated in one of the 38 Italian institutions (hospitals, research institutes, etc.) participating in the network. Melanoma-specific survival and Overall survival were calculated. Kaplan-Meier curves and medians of OS and 95% CI are presented overall and by immunotherapy and target treatments. The Log-rank test compared curves by treatments. Multivariate Cox regression models were used to estimate the hazard ratios adjusting for confounders and other prognostic factors. Results: The median follow-up time was 36 months (range 1.2-185.1). 787 CMM were included in the analysis with completed information about therapies.Global immunotherapy showed a significant improved survival compared with all other therapies (p=0.001). 75% was the highest reduction of death reached by nivolumab/pembrolizumab immunotherapy (anti-PD1 HR=0.25 95% CI 0.14-0.42), globally immunotherapy was significantly associated with improved survival, either for anti-CTL A4 monotherapy or combined with anti-PD1 (HR=0.47;95% CI 0.33-0.66 and HR=0.26; 95% CI 0.15-0.46, respectively). Conclusions: The nivolumab/pembrolizumab and the combination of ipilimumab can be considered the best therapy to improve survival in a real-world-population. The CNMR can complement clinical registries with the intent of improving cancer management and standardizing cancer treatment.

The early detection of cutaneous melanoma, a potentially lethal cancer with rising incidence, is key to increase survival and therapeutic adjustment. Especially in stages II-IV biomarkers are urgently needed for adjuvant therapy purposes after resection and for treatment of metastatic patients. We here investigated if fatty acid (FA) and protein composition of small extracellular vesicles (sEV) deriving from plasma of 0-I, II, and III-IV stage melanoma patients (n=38) could reflect disease stage and thus function as biomarker. The subpopulation of sEV expressing CD81 (CD81sEV) was isolated by an ad hoc immune affinity technique from microvesicle-depleted plasma. Biological macromolecules were investigated by gas chromatography and mass spectrometry in CD81sEV. A higher content of FA and a decrease in Saturation Index (C18:0/C18:1), already detectable in early stages, distinguished patients’ from healthy donor CD81sEV. Proteomics (identifier PXD024434) detected an exclusive and significant increase of CD14, PON1, PON3 and APOA5 in stage II and a significant decrease of Rap1b in stage III-IV CD81sEV. The FA and proteomic stage dependent CD81sEV signature strengthens the potential of circulating sEV studies in providing discriminatory information for early diagnosis, prediction of metastatic behavior and follow up of melanoma patients.

Current methodologies for developing patient-derived xenografts (PDX) in humanized mice in preclinical trials to test response to immune-based therapies are limited by graft versus host disease. Here we compared two approaches for establishing PDX tumors in humanized mice: 1) PDX are first established in immune-deficient mice; 2) PDX are initially established in humanized mice, before transplanting established PDX’s to a larger cohort of humanized mice for preclinical trials. With the first approach, there was rapid wasting of PDX-bearing humanized mice with high levels of activated T cells in the circulation and organs, indicating immune-mediated toxicity. In contrast, with the second approach, toxicity was less of an issue and long-term human melanoma tumor growth and maintenance of human chimerism was achieved. Pre-clinical trials from the second approach revealed that rigosertib, but not anti-PD-1, increased CD8/CD4 T cell ratios in spleen and blood and inhibited PDX tumor growth. Resistance to anti-PD-1 was associated with limited infiltration of CD8+ T cell into the tumor. Our findings suggest that it is essential to carefully manage immune editing by first establishing PDX tumors in the presence of human immune cells before expanding PDX tumors into a larger cohort of humanized mice to evaluate therapy response.

The human scalp is a common site of skin cancer in humans, with non-melanoma skin cancer being exceedingly common. In this review, two dermatologists with extensive experience in cutaneous oncology will discuss unique features of the epidemiology of cancer of the scalp. Clinical observations on these common skin cancers lead to insight into the pathogenesis and potential prevention and treatment of cutaneous scalp neoplasia. Our hypothesis is that the presence of hair protects against the development of skin cancer, but not by serving as a physical shield, but rather by providing a continuous IL-17 biased immunosurveillance. Loss of hair allow release from immunosurveillance, resulting in expansion of neoplastic cells towards skin cancer. Both hair follicles and metabolic changes in stroma allow permissiveness for tumor promotion.

Reactive oxygen species (ROS) are intermediates in oxidation-reduction reactions with the capacity to modify biomolecules and temporarily or permanently alter cell behaviour through signalling pathways under physiological and pathophysiological conditions where there is an imbalance between oxidative factors and the antioxidant response of the organism, a phenomenon known as oxidative stress. Evidence suggests that differential modulation of ROS-mediated oxidative stress occurs in the pathogenesis and progression of melanoma, and that this imbalance in redox homeostasis appears to be functionally linked to microRNA-mediated non-mutational epigenetic reprogramming involving genes and transcription factors. The relationship between ROS-mediated stress control, tumour microenvironment and microRNAs expression in melanoma is not fully understood. The aim of this review is to analyze the involvement of miRNAs in the modulation of signalling pathways involved in ROS-mediated oxidative stress in melanoma. It is hoped that these considerations will contribute to the understanding of the mechanisms associated with a potential epigenetic network regulation, where the modulation of oxidative stress is consolidated as a common factor in melanoma and therefore a potential footprint poorly documented.

Background: Cutaneous melanoma arises from skin melanocytes and has a high risk of metastatic spread. Despite better prevention, earlier detection, and the development of innovative therapies melanoma incidence and mortality increase annually. Major clinical risk factors for melanoma include fair skin, an increased number of nevi, the presence of dysplastic nevi, and a family history of melanoma. However, several external inducers seem to be associated with melanoma susceptibility such as environmental exposure, primarily unprotected sun experience, alcohol consumption, and heavy metals. In recent years, epidemiological studies have highlighted a potential risk of β-hexachlorocyclohexane (β-HCH), the most studied organochlorine pesticide, on cancer induction including melanoma. Methods: We evaluated in vitro the impact of this pollutant on epidermal and dermal cells, attempting to describe mechanisms that could render cutaneous cells more prone to oncogenic transformation. Results: We demonstrated that β-HCH impacts melanocyte biology with a highly cell-type specific signature that involves perturbation of AKT/mTOR and Wnt/β-catenin signaling, and AMPK activation that converges in lowering energy reserve, cell proliferation, and pigment production. Conclusion: In conclusion, long-term exposure to persistent organic pollutants damages melanocyte metabolism in the function of the melanin content with a consequent reduction of melanogenesis indicating a potential augmented skin cancer risk.

(1) Background: Melanoma is the most aggressive tumor located at the skin level and the man-agement of this pathology requires a correct staging as well as a modern oncological treatment, adapted to each patient. The main objective of the study is to determine the variability of lymphatic drainage in the case of melanomas located on the trunk; (2) Methods: This retrospective study in-cluded 62 cases of melanoma located on the trunk operated between July 2019 and March 2023 in which SLNB was performed and a total of 84 lymph node were excised; (3) Results: Patients had an average age of 54.5 years old, while melanomas had a mean Breslow index of 2.3 mm. The distri-bution of trunk melanomas was: upper trunk 54 cases, lower trunk 30 cases (64.3 % vs. 35.7%). The type of anesthesia chosen was general anesthesia in 53 cases, respectively spinal anesthesia in 9 cases (85.5% vs. 14.5%, p<0.001). The number of sentinel lymph nodes was 54 for melanomas lo-cated on the upper trunk, 8 cervical and 46 axillary, respectively 30 sentinel lymph nodes in cases of melanomas of the lower trunk, 16 at the axillary level and 14 at the inguinal level; (4) Conclusions: Lymph node involvement in melanoma represents an important prognostic factor and the different lymphatic drainage pathways in relation to the location of the primary tumor represents an im-portant objective in the management of this pathology.

Gut microbiota is considered a key player modulating the efficacy of immune checkpoint inhibitor therapy. The study investigated the association between response to the anti-PD-1 therapy and the baseline gut microbiome in the Polish cohort of melanoma patients, alongside selected agents modifying the microbiome. Sixty-four melanoma patients enrolled for the anti-PD-1 therapy and 10 healthy subjects were recruited. Response to the treatment was assessed according to the response evaluation criteria in solid tumors, and patients were classified as responders or non-responders. The association between selected extrinsic factors and response was investigated using questionnaire-based analysis, and metataxonomics of the microbiota. The Bacteroidota to Firmicutes ratio was higher, and the richness was decreased in the responders. The abundance of Prevotella copri and Bacteroides uniformis was related to the response, whereas non-responder gut microbiota was enriched with Faecalibacterium prausnitzii and Desulfovibrio intestinalis, and some unclassified Firmicutes. Dietary patterns, including plant, dairy, and fat consumption, but also gastrointestinal tract functioning were significantly associated with the therapeutic effects of the therapy. The specific gut microbiota alongside diet were found associated with response to the therapy in the Polish population of melanoma patients.

The incidence of cutaneous melanoma has been increasing in the last decades among fair-skinned population. Despite etiology is complex and multifactorial, the exposure to ultraviolet radiation (UVR) is the most consistent modifiable risk factor associated with melanoma. Several factors influence the amount of UVR reaching Eart’s surface. The aim of our study is to explore the association between melanoma and altitude in an area characterized by a mixed geographic morphology, such as in the Veneto region. For this purpose, 2752 melanoma patients, who referred to our attention between 1998 and 2014, were included in this study. For each patient we extracted demographic, histological and clinical-survival data. Head/neck and acral melanoma were more common in patients from the hills and the mountains, while the prevalence of limb and trunk melanoma was higher in patients living in plain and coastal areas. With increase of altitude, the Breslow thickness, ulceration and mitotic rate get worse but no significant difference was observed in overall and disease free-survival. Geographical area of origin of melanoma patients and the “coast-plain-hill gradient” could help to estimate the influence of different sun exposure and to explain the importance of vitamin D level in skin-cancer control.

Uveal melanoma is the most common intraocular malignancy and arises from melanocytes in the choroid, ciliary body, or iris. Radiotherapy is the mainstay of therapy for most patients with localized uveal melanoma. Another RT technique used in the treatment of uveal melanomas is charged-particle radiotherapy. Photodynamic therapy is based on the selective destruction of cancer cells or pathological vessels. High-Intensity Focused Ultrasound (HIFU) is a promising technology of thermal destruction of solid tumors located deep under the skin. The principle of operation is based on the heating of a tumor. Sonodynamic therapy (SDT) induces the reactive oxygen species and kills cancer cells. Electroporation applied in vivo delivers drugs or genetic material from the intercellular space to cells. Iontophoresis is a technique in which using electric current increases the biodistribution of drugs in the eyeball. Transcorneal iontophoresis has been shown to increase the local concentration of antibacterial and antifungal drugs, steroids, DNA, and RNA molecules. Theranosticsincorporates diagnostic imaging and therapy. Although no theranostic markers have been developed specifically for uveal melanoma, some NPs have already found use in ophthalmology. UM presents an unmet clinical need. Novel eye-preserving therapeutic approaches for the localized disease are needed.

Malignant melanoma is a highly aggressive type of cancer that requires radical treatment strategies to inhibit the cancer cell progression and metastasis. In recent years, preclinical research and clinical trials on melanoma treatment are considerably focused on the adjuvant-based immunotherapy for enhancing the immune response of innate immune cells against cancer cells. However, the clinical outcome of these adjuvant-based treatments are inadequate due to improper delivery system for these immune activators to reach the target site. Hence, we developed a vaccine formulation containing tumor lysate protein (TL) and poly I:C (PIC) complexed with positively charged poly (sorbitol-co- polyethylenimine (PEI)(PSPEI). The resulting ionic PSPEI-polyplexed antigen/adjuvant (PAA) (PSPEI-PAA) nanocomplexes were stable at the physiological condition, non-toxic and enhanced intracellular uptake in immature dendritic cells. In murine B16F10 tumor xenograft model, PSPEI-PAA nanocomplexes significantly suppressed tumor growth and did not exhibit any noticeable sign of toxicity. Additionally, the cytotoxic T lymphocytes (CTLs) assay involving co-culturing of splenocytes isolated from the PSPEI-PAA-treated mice with that of B16F10 cells significantly revealed enhanced cancer killing by the TL-reactivated CTLs compared to untreated control mice bearing tumor. Therefore, we strongly believe that PSPEI-PAA nanocomplexes could be an efficient antigen/adjuvant delivery system and also enhance the antitumor immune response against melanoma tumor in the future clinical trials.

Conjunctival melanoma (Co-M) is an aggressive, invasive eye and eyelid cancer. Its global inci-dence of ~1 in a million is increasing at a rate ratio of ~1.4, but this rises sharply in over 65-year-olds. Although rare, Co-M has a devastating impact on the lives of those who develop it. Co-M is often misdiagnosed or overlooked leading to vision loss either from destructive effects of the tumour or side effects of therapy, facial disfigurement from radical surgery, and death from metastases. Due to its rarity, there is limited evidence for diagnosis and management; hence, there is no standardised treatment and not all cases are referred to a specialised ocular oncology centre. Recent progress in cancer immunology and genetics have revolutionised treatment of cutaneous melanoma, which share some similarities to Co-M. A better understanding of Co-M and its precursor lesions is urgently needed to lead the development of novel targeted and immuno-therapies both for local tumour control and disseminated disease. This review aims to provide a comprehensive clinical overview of the current knowledge of Co-M, its epidemiology, pathogenesis, presentation, diagnosis, management, and recent advances in novel biological therapies for personalised treatment of this disease.

Background: Cutaneous Melanoma (SKCM) is characterized by significant heterogeneity in its molecular, genomic, and immunologic characteristics. Methods: Whole transcriptome RNAseq data from The Cancer Genome Atlas of SKCM (n=328) was utilized. The immune microenvironment was characterized using CIBERSORTX to identify immune cell type composition. Unsupervised hierarchical clustering was performed based on immune cell type content. Samples were separated into those obtained from the primary tumor site and regional skin or soft tissue (locoregional), or distant metastasis and regional lymph node (metastatic). Analysis of overall survival (OS) was performed using Kaplan-Meier estimates and Cox-regression multivariable analyses. Results: Four immune clusters were identified, largely defined by lymphocyte:monocyte (L:M) ratio, monocyte-enrichment, and M0-macrophage-enrichment (L:MLow, MonocyteHigh, M0High; L:MLow, MonocyteMid, M0Low; L:MMid, MonocyteLow, M0Low; L:MHigh, MonocyteLow, M0Low). The L:MLow, MonocyteHigh, M0High cluster demonstrated significantly worse OS than clusters 2-4 in the locoregional group (HR 2.804, 95% CI 1.262–6.234, p=0.0114). Membership in the L:MLow, MonocyteHigh, M0High cluster was an independently poor prognostic factor for survival (HR 3.03, 95% CI 1.12–8.20, p=0.029). The L:MLow, MonocyteHigh, M0High cluster correlated with higher rates of metastasis and decreased predicted response to immune checkpoint blockade compared to the other clusters as determined by the Tumor Immune Dysfunction and Exclusion tool (TIDE). Conclusion: Distinct tumor immune clusters with a M0-macrophage-enriched, L:M ratio low phenotype in the primary melanoma tumor site independently characterize an aggressive phenotype that may differentially respond to treatment.

Melanoma is the most aggressive and deadly form of skin cancer, and its incidence has been steadily increasing over the past few decades, particularly in the Caucasian population [1]. Current treatment strategies, the combination of BRAF and MEK inhibitors (BRAF/MEKi) in BRAFV600 mutant melanoma, and immune checkpoint inhibitors (ICI), have changed the clinical evolution of this disease [2]. However, a significant percentage of patients do not benefit from these therapies. Therefore, to improve patient selection, it is imperative to look for novel biomarkers. Immune subsets, particularly the quantification of lymphoid populations, could contribute to the identification of ICI responders. The aim of this review is to thoroughly examine significant published data on this topic in melanoma patients and to evaluate the potential role of lymphoid subsets as prognostic and predictive response biomarkers.

Immune checkpoint inhibitors (ICI) have been widely used in melanoma, but to identify melanoma patients with survival benefit from ICI is still a big challenge. There is an urgent need for prognostic signatures improving the prediction of immunotherapy responses of cancer patients. We used data from EMBL-EBI database and analyzed RNA-seq information and clinical profiles in melanoma. Weighted gene co-expression network analysis (WGCNA) was used to identify the key module, then nonnegative matrix factorization (NMF) was conducted to cluster patients into two different cluster and compared them regarding overall survival (OS) and progression-free survival (PFS). Subsequently, the differentially expressed genes (DEGs) between different clusters were identified, and their function and pathway annotation were performed. 91 melanoma biopsies with complete survival information were included in our analyses and we first identified the key module (magenta) by WGCNA, then identified nine prognostic lncRNAs (ENSG00000258869, ENSG00000179840, ENSG00000206344, ENSG00000226777, ENSG00000205018, ENSG00000204261, ENSG00000163597, ENSG00000197536, and ENSG00000263069) signature that predicted for OS and PFS in patients treated with ICI by NMF. Finally, enrichment analysis showed that the functions of DEGs between two consensus clusters were mainly related to the immune process and treatment. In summary, the nine lncRNAs signature is a novel effective predictor for OS and PFS in melanoma patients treated with ICI.

Background. Neoplastic diseases and infections have become the leading causes of death in SLE in recent decades. Cancers and infections were also precipitating factors in the development of catastrophic APS. Case summary. We describe two patients: one of them had definite antiphospholipid syndrome (APS) and melanoma and the other had definite systemic lupus erythematosus (SLE) with APS, melanoma, infiltrative tuberculosis and severe Herpes Zoster (HZ). Management of patients with SLE concurrent with APS is a rather difficult task in rheumatology practice. In addition to kidney damage and cardiovascular disease, infections and malignancies are a significant cause of death in this cohort. The risk of malignancy in SLE is of considerable interest, since the immune and genetic pathways underlying the pathogenesis of this disease, as well as the immunosuppressive therapy, can significantly alter the risk. Both patients still had reliable APS, confirmed by triple-positive aPL. Both were at high risk of thrombosis. Patients ' adherence to treatment with direct oral anticoagulants and relapse of thrombosis on the background of rivaroxaban were noted. Conclusion. The cases where cancer or tuberculosis develops in the presence of rheumatic diseases are not so common and complicate the possibilities of therapeutic approaches, limiting the use of drugs that are not regulated by clinical recommendations.

Advanced cutaneous melanoma is considered the most aggressive type of skin cancer with variable rates of treatment response. Nowadays, there are available some classes of immunotherapy and target therapy for its treatment. Immunotherapy can inhibit tumor growth and its recurrence by triggering host's immune system, while targeted therapy acts inhibiting specific molecules or signaling pathways. However, melanoma response to these treatments are highly heterogenous, and frequently become resistant. Epigenome (DNA/histone modification) contribute to cancer initiation and progression. Epigenetic alterations are divided into four levels of gene expression regulation: DNA methylation, histone modification, chromatin remodeling and non-coding RNAs regulation. The deregulation of lysine methyltransferase enzymes is associated with tumor initiation, invasion, development of metastases, changes in immune microenvironment and drug resistance. The study of lysine histone methyltransferase (KMT) inhibitors is important to cancer epigenetic mechanisms understanding and to biological processes. In addition to immunotherapy and target therapy, the research and development of KMT inhibitors is ongoing. Many studies are exploring the therapeutic implications and possible side effects of these compounds, besides their adjuvant potential to the approved current therapies. Importantly, as with any drug development, safety, efficacy, and specificity are crucial considerations when developing KMT inhibitors for clinical applications.

Immune checkpoint inhibitors (ICI) are currently use in a wide range of tumors, but only 20-40% of patients achieve clinical benefit. Aim of our study was to find predictive biomarkers of ICI treatment. We analyzed by immunohistochemistry various cell subsets, including CD3+ cells, CD8+ cells, CD68+ cells, CD20+ cells, FoxP3+ cells, and molecules as LAG-3, IDO1, TGfβ. Comprehensive genomic profiles were analyzed. Correlation of various biomarkers with efficacy of ICI treatment in patients with advanced solid tumors was evaluated. We evaluated 56 patients treated with ICI monotherapy. Longer median progression-free survival (PFS) was found in tumors negative for nuclear FoxP3 (P = 0.002, HR 0.14) and in TMB-high tumors (P = 0.024, HR 0.38). Longer overall survival (OS) was found in patient with intraepithelial CD8 negativity (P = 0.045, HR 0.47). In malignant melanoma CD68 negativity, FoxP3 negativity and PDL TPS ≥ 1 was associated with longer PFS. In NSCLC FoxP3 was associated with longer PFS and OS. We found that absence of expression of several biomarkers such as CD68 and FoxP3 is associated with better survival. TMB-high and PD-L1 expression not universally but in certain disease could predict response.

In comparison to other human cancer types, malignant melanoma exhibits the greatest amount of heterogeneity. After DNA-based detection of the BRAF V600E mutation in melanoma patients, targeted inhibitor treatment is the current recommendation. This approach, however, does not take the abundance of the therapeutic target, i.e., the B-raf V600E protein, into consideration. As shown by immunohistochemistry, the protein expression profiles of metastatic melanomas do clearly reveal the existence of inter- and intra-tumor variability. Nevertheless, the technique is only semi-quantitative. To quantitate the mutant protein there is a fundamental need for more precise techniques that are aimed at defining the currently non-existent link between the levels of the target protein and subsequent drug efficacy. Using cutting-edge mass spectrometry combined with DNA and mRNA sequencing, the mutated B-raf protein within metastatic tumors was quantitated for the first time. B-raf V600E protein analysis revealed a subjacent layer of heterogeneity for mutation-positive metastatic melanomas. These were characterized into two distinct groups with different tumor morphologies, protein profiles and patient clinical outcomes. This study provides evidence that a higher level of expression for the mutated protein is associated with a more aggressive tumor progression. Our study design that is comprised of surgical isolation of tumors, histopathological characterization, tissue biobanking, and protein analysis may enable the eventual delineation of patient responders/non-responders and the subsequent therapy of malignant melanoma.

To develop peptide drugs targeting integrin receptors, synthetic peptide ligands endowed with well-defined selective binding motifs are necessary. The snake venom KTS-containing disintegrins, that selectively block collagen α1β1 integrin, were used as lead compounds for the synthesis and structure-activity relationship of a series of linear peptides containing the KTS-pharmacophore and alternating natural amino acids and 3-aminobenzoic acid (MABA). To ensure a better stiffness and metabolic stability, one, two and three MABA residues, were introduced around the KTS pharmacophore motif. Molecular dynamics simulations have determined that the solution conformation of MABA peptide 4 is more compact, underwent larger conformational changes until convergence, and spent most of the time in a single cluster. The peptides’ binding affinity has been characterized by enzyme linked immunosorbent assay in which the most potent peptide 4 inhibited with IC50 of 324±8 µM and 550±45 µM the binding of GST-α1-A domain to collagen IV fragment CB3, and the cell adhesion to collagen IV using α1-overexpressor cells, respectively. Docking studies and MM-GBSA calculations confirmed that peptide 4 binds a smaller region of the integrin near the collagen- binding site and penetrated deeper into the binding site near Trp1. Peptide 4, inhibited tube formation by endothelial cell migration in the Matrigel angiogenesis in vitro assay. Peptide 4 was acutely tolerated by mice, showed stability in human serum, decreased tumor volume and angiogenesis, and significantly increased the survival of mice injected with B16 melanoma cells. These findings propose that MABA-peptide 4 can further serve as an α1β1-integrin antagonist lead compound for further drug-optimization in angiogenesis and cancer therapy.

The incidence of melanoma, the most lethal form of skin cancer, has increased due to ultraviolet exposure. The molecular characterization of melanomas has shown a high mutational burden led to the identification of some recurrent genetic alterations. BRAF gene is mutated in 40-50% of melanomas and its role in melanoma development is paramount. BRAF mutations confer constitutive activation of MAPK signalling. The large majority (abou 90%) of BRAF mutations occur at amino acid 600; the majority are BRAFV600E mutations and less frequently BRAFv600K, V600D and V600M. The introduction of drugs that directly target BRAF-mutant protein (BRAF inhibitors) and of agents that stimulate immune response through targeting of immune check inhibitor consistently improved the survival of melanoma BRAFV600-mutant patients with unresectable/metastatic disease. In parallel, studies in melanoma stage II-III patients with resectable disease have shown that adjuvant therapy with ICIs and/or targeted therapy improves PFS and RFS, but not OS compared to placebo; however, neoadjuvant therapy plus adjuvant therapy improved therapeutic response compared to adjuvant therapy alone.

Targeted therapies are effective cancer treatments when accompanied by accurate diagnostic tests that can help identify patients that will respond to those therapies. The YAP/TAZ-TEAD axis is activated and plays a causal role in several cancer types, and TEAD inhibitors are currently in early phase clinical trials in cancer patients. However, mutations that predict YAP/TAZ-TEAD activation are not commonly found in most cancer types, making it hard to determine which tumors are de-pendent upon YAP/TAZ-TEAD. Here, we used a combination of RNA-seq and bioinformatics analysis of metastatic melanoma cells to develop a YAP/TAZ gene signature. We found that the genes in this signature are TEAD-dependent, and that their expression strongly correlates with YAP/TAZ activation in human melanomas. Using DepMap dependency data, we found that this YAP/TAZ signature was predictive of melanoma cell dependence upon YAP/TAZ or TEADs. Importantly, this was not limited to melanoma because this signature was also predictive when tested on a panel of over 1000 cancer cell lines representing numerous distinct cancer types. Our results suggest that YAP/TAZ gene signatures like ours may be an effective tool to predict tumor cell sensitivity to YAP/TAZ-TEAD inhibition, and thus provide a means to identify patients likely to benefit from TEAD inhibitors.

The scalp is a unique anatomical region with distinct challenges for reconstruction, especially in cases of melanoma excision. This study explores the utilization of the O-Z flap technique as an alternative approach for patients with melanoma, where traditional free flap reconstruction may not be feasible due to age or underlying health conditions. However, in this case, the patient had a history of angina and was unwilling to undergo a long operation due to his advanced age. This study highlights the importance of following NCCN guidelines for melanoma resection margins based on tumor thickness and underscores the value of staged resection planning to minimize deficits. This requires an individualized approach as each patient may have different circumstances (general health condition, age, compliance, etc.). So we planned a staged excision first. In the first surgery, we would resect the tumor minimally and then determine the exact size of the tumor. Then, in the second surgery, we resected it with a safety margin according to the guidelines. The O-Z flap, a local flap with an "O"-shaped defect and "Z"-shaped incision line, is introduced as a reconstructive option. The surgical procedure, advantages, and limitations of this approach are discussed. This study provides valuable insights into achieving successful scalp reconstruction while considering aesthetic outcomes and patient-specific factors.

Super-high (x400) magnification dermoscopy (D400) is a new non-invasive imaging technique that has been shown to add information for the differential diagnosis of melanocytic lesions in a pilot study. Our study aimed to confirm if D400 can add details for the discrimination of clinically atypical nevus and melanoma. This is a retrospective observational, multicentric study enrolling patients who received an x20 (D20) and x400 (D400) magnification dermoscopic examination of pigmented skin lesions. Dermoscopic images were retrospectively evaluated by three observers for the presence/absence of nine D20 and twenty D400 dermoscopic features defined in the previous pilot study. Univariate and multivariate analyses were carried out to find predictors of benign and malignant behaviors. At D20 atypical pigment network, blue-whitish veil, atypical vascular pattern, regression, and homogenous pattern were more frequent in melanoma than in nevi (p&lt;0.001). At D400 melanoma showed more frequently than benign lesions melanocytes with an irregular arrangement and irregular in shape and size (p&lt;0.001). Network with edged papillae was more frequent in benign lesions than melanomas (p&lt;0.001). Our study confirms that D400 can identify melanocytes with an irregular arrangement and irregular in shape and size in melanomas, adding information to the conventional D20 examination.

Rising incidences of cutaneous melanoma have fueled the development of statistical models that predict the individual melanoma risk. Our aim was to assess the validity of published prediction models for incident cutaneous melanoma using a standardized procedure based on PROBAST (Prediction model Risk Of Bias ASsessment Tool). We included studies that were identified by a recent systematic review and updated the literature search to ensure that our PROBAST rating included all relevant studies. Six reviewers assessed the risk of bias (ROB) for each study using the published “PROBAST Assessment Form” that consists of four domains and an overall rating of ROB. We further examined a temporal effect regarding changes in overall and domain-specific ROB rating distributions. Altogether 42 studies were assessed, of which a vast majority (n=34; 81%) was rated as having high ROB. Only one study was judged as having low ROB. The main reasons for high ROB ratings were the use of hospital controls in case-control studies and the omission of any validation of prediction models. However, our results of the temporal analysis showed a significant reduction in the number of studies with high ROB for the domain analysis. Nevertheless, the evidence base of high-quality studies that can be used to draw conclusions on the prediction of incident cutaneous melanoma is currently much weaker than the high number of studies on this topic would suggest.

Melanoma is considered the most serious and aggressive type of skin cancer, and metastasis appears to be the most important factor in prognosticating this type of cancer. With the emergence of new therapeutic strategies for metastatic melanoma that have shown improvement in patient survival, we developed a transfer learning-based biomarker discovery model that could help in the diagnosis and prognosis of this disease. After applying it to the ensemble machine learning model, results reveal that the genes we found show consistency with other methodologies previously applied to the same TCGA (The Cancer Genome Atlas) data set, and our methods found novel biomarker genes as well. Our ensemble model achieved Area Under the Receiver Operating Characteristic (AUC) of 0.9861, an accuracy of 91.05, and an F1 score of 90.60 using an independent validation data set. This study was able to identify potential genes for diagnostic classification (C7 and GRIK5) and diagnostic and prognostic biomarkers (S100A7, S100A7, KRT14, KRT17, KRT6B, KRTDAP, SERPINB4, TSHR, PVRL4, WFDC5, IL20RB). We also assessed the potential sources of bias for our model and confirmed some of them by the model's performance.

Ultraviolet (UV) radiation is a strong environmental carcinogen responsible for the pathogenesis of most skin cancers, such as malignant melanoma (MM) and non-melanoma (keratinocyte) skin cancers. The carcinogenic role of UV was firmly established based on epidemiological evidence and molecular findings of the characteristic mutation signatures which occur during excision repair of cyclobutane pyrimidine dimers and 6,4-photoproducts. The role of UV in the pathogenesis of mycosis fungoides (MF), the most common primary cutaneous T-cell lymphoma, remains controversial. Here, we performed whole exome sequencing of 61 samples of MF cells microdissected from the cutaneous lesions, and compared their mutational signatures to 340 MM. The vast majority of MM mutations had a typical UV mutational signature (SBS 7, SBS 38, DSB 1) underscoring the key role of ultraviolet as a mutagen. In contrast, the SBS 7 signature in MF comprised &lt;5% of all mutations. SBS 7 was higher in the intraepidermal MF cells (when compared to the dermal cells) and in the cells from tumors as compared to early-stage plaques. In conclusion, our data do not support the pathogenic role of UV in the pathogenesis of MF and suggest that the UV mutations are the result of the cumulative, environmental ultraviolet exposure of cutaneous lesions, rather than an early mutagenic event.

Cancer is a complex disease, considered a major public health problem worldwide. Among the types of cancer, melanoma, and leukemias present high mortality rates in Brazil and worldwide. Currently, conventional cytotoxic treatments cause severe side effects by the non-selectivity between normal cells and cancer cells. Therefore, molecules of natural origin with more efficient anticancer properties and that present fewer adverse effects are of extreme importance for cancer therapy and improvement in patients’ quality of life. This study isolated, identified, and characterized the chemical structure of a new anthraquinone present in the extract of the roots of Senna velutina. In addition, we sought to evaluate the anticancer potential of this molecule against melanoma and leukemic cell lines and identify the pathways of cell death involved. To this end, a novel anthraquinone was isolated from the barks of the roots of S. velutina, analyzed by HPLC-DAD, and its molecular structure was determined by NMR. Subsequently, their cytotoxic activity was evaluated by the MTT method against non-cancerous, melanoma, and leukemic cells. The migration of melanoma cells was evaluated by the scratch assay. By flow cytometry technique, the apoptosis process, caspase-3 activation, analysis of mitochondrial membrane potential, and measurement of ROS were evaluated. In addition, the pharmacological cell death inhibitors NEC-1, RIP-1, BAPTA, Z-VAD, and Z-DEVD were used to confirm the related cell death mechanisms. With the results, it was possible to elucidate the novel compound characterized as 2'-OH-Torosaol I. In normal cells, the compound showed no cytotoxicity in PBMC but reduced the cell viability of all melanoma and leukemic cell lines evaluated. 2'-OH-Torosaol I inhibited chemotaxis of B16F10-Nex2, SK-Mel-19, SK-Mel28 and SK-Mel-103. The cytotoxicity of the compound was induced by apoptosis via the intrinsic pathway with reduced mitochondrial membrane potential, increased levels of reactive oxygen species, and activation of caspase-3. In addition, the inhibitors demonstrated the involvement of necroptosis and CA+ in the death process and confirmed caspase-dependent apoptosis death as one of the main programmed-cell death pathways induced by 2'-OH-Torosaol I. Taken together, the data characterize the novel anthraquinone 2'-OH-Torosaol I, demonstrating its anticancer activity and potential application in cancer therapy.

Epidemiological evidence points to an inverse association between Parkinson's disease (PD) and almost all cancers except melanoma, for which this association is positive. The results of many studies have found that patients with PD are at reduced risk of the majority of neoplasm occurrence and death. Several potential biological explanations exist for the inverse relationship between cancer and PD. Recent results identified several PD-associated proteins and factors mediating cancer development and cancer-associated factors affecting PD. Accumulating data points to the role of genetic traits, members of the synuclein family, neurotrophic factors, ubiquitin-proteasome system, circulating melatonin, and transcription factors as such mediators. We present recent data about shared pathogenetic factors and mediators that might be involved in the association between these two diseases. We also discuss how these factors, individually or in combination, may be involved in pathology, serve as links between PD and cancer, and affect the prevalence of these disorders. Identification of these factors and investigations of their mechanisms will lead to the discovery of new targets for the treatment of both diseases

Despite numerous studies on cancer treatment, cancer remains a challenging disease to cure, even after decades of research. In recent years, cancer vaccine has emerged as a promising approach for cancer treatment, offering few unexpected side effects compared to existing therapies. How-ever, cancer vaccine faces obstacles to commercialization due to its low efficacy. Particularly, the Toll-like receptor (TLR) adjuvant system, specifically the TLR 7/8 agonist, has shown potential for activating Th1 immunity, which stimulates both innate and adaptive immune responses through T cells. In this study, we developed ProLNG-S, a cholesterol-conjugated form of resiquimod (R848), to enhance immune efficacy by stimulating the immune system and reducing toxicity. ProLNG-S was formulated as ProLNG-001, a positively charged liposome, and co-administered with oval-bumin (OVA) protein in the B16-OVA model. ProLNG-001 effectively targeted secondary lym-phoid organs, resulting in a robust systemic anti-tumor immune response and tumor-specific T cell activation. Consequently, ProLNG-001 demonstrated potential for preventing tumor progression and improving survival compared to AS01 by enhancing anti-tumor immunity.

Uveal melanoma (UM) is the most common primary cancer of the eye and is associated with a high rate of metastatic death. UM can be stratified into two main classes based on metastatic risk, with class 1 UM having a low metastatic risk and class 2 UM having a high metastatic risk. Class 2 UM have a distinctive genomic, transcriptomic, histopathologic, and clinical phenotype characterized by biallelic inactivation of the BAP1 tumor suppressor gene, an immune suppressive microenvironment enriched for M2-polarized macrophages, and poor response to checkpoint inhibitor immunotherapy. To identify potential mechanistic links between BAP1 loss and immune suppression in class 2 UM, we performed an integrated analysis of UM samples, as well as genetically engineered UM cell lines and uveal melanocytes (UMC). Using RNA sequencing (RNA-seq), we found that the most highly up-regulated gene associated with BAP1 loss across these datasets was PROS1, which encodes a ligand that triggers phosphorylation and activation of the immunosuppressive macrophage receptor MERTK. The inverse association between BAP1 and PROS1 in class 2 UM was confirmed by single-cell RNA-seq, which also revealed that MERTK was up-regulated in CD163+ macrophages in class 2 UM. Using ChIP-seq, BAP1 knockdown in UM cells resulted in an accumulation of H3K27ac at the PROS1 locus, suggesting epigenetic regulation of PROS1 by BAP1. Phosphorylation of MERTK in RAW 264.7 monocyte-macrophage cells was increased upon co-culture with BAP1-/- UMCs, and this phosphorylation was blocked by depletion of PROS1 in the UMCs. These findings were corroborated by multi-color immunohistochemistry, where class 2/BAP1-mutant UMs demonstrated increased PROS1 expression in tumor cells and increased MERTK phosphorylation in CD163+ macrophages compared to class 1/BAP1-wildtype UMs. Taken together, these findings provide a mechanistic link between BAP1 loss and suppression of the tumor immune microenvironment in class 2 UMs, and they implicate the PROS1-MERTK pathway as a potential target for immunotherapy in UM.