Treatment Of Melanoma Research Articles

Abstract A004: RNA splicing alterations in the development of acquired MAPKi resistance in melanoma

Abstract The standard treatment for melanoma with a BRAF mutation involves Mitogen-Activated Protein Kinase inhibitors (MAPKi), which target the aberrant MAPK signaling pathway. Although patients initially respond well to this therapy, many develop acquired resistance over time. This resistance can be attributed to various altered signaling pathways, including the reactivation of the MAPK pathway, activation of alternative survival pathways like PI3K/PTEN/AKT, engagement of receptor tyrosine kinases (RTKs) such as PDGFRβ and EGFR, and developmental pathways. Despite extensive omics studies aimed at deciphering the mechanisms behind acquired resistance, the specific alterations within these pathways remain poorly understood. To gain further insights into acquired MAPKi resistance in melanoma, we explored the role of RNA splicing events by analyzing publicly available datasets of pre- and post-MAPKi treated melanoma from patient-derived cell lines and in vitro studies using PDX models. We investigated differential transcript usage (DTU) to detect specific splice variants altered during the development of resistance. Our analysis revealed significant transcript alterations during on-treatment that reverted to baseline states once resistance was established, underscoring the dynamic and adaptive nature of these changes. Genes with DTU were enriched in pathways related to MAPKi resistance, such as the MAPKi signaling pathway, PI3K/AKT pathway, and signaling by RTKs. Furthermore, the DTU-centered analysis provided better insights into MAPKi resistance mechanisms compared to standard differential gene expression (DEG) analysis, with DTUs showing higher enrichment scores in MAPKi resistance-related pathways. Further, identifying developmental splicing signatures highlights the complexity of MAPKi resistance, as it reveals significant upregulation of transcripts associated with embryonic melanoblast stem cells (MSCs) among the altered transcripts in on-treatment cell lines. This reprogramming through RNA splicing may confer an adaptive advantage, enabling melanoma cells to revert to a more plastic, stem-like state, with developmental splicing events playing a crucial role in the adaptive response to MAPKi therapy. Next, using a regulatory model based on the expression of splicing factors (SFs), we accurately predicted transcript alterations in on-treatment samples and identified key SFs. Our study highlights the crucial role of RNA splicing in the adaptive response of melanoma cells to MAPKi treatment. These insights pave the way for future research and therapeutic strategies focusing on RNA splicing to combat drug resistance in cancer. Citation Format: Sumit Mukherjee, Arashdeep Singh, Hyunjeong Joo, Sumeet Patiyal, Hyungsoo Kim, Lipika R. Pal, Kun Wang, Chi-Ping Day, Ze’ev A Ronai, Eytan Ruppin, Sridhar Hannenhalli. RNA splicing alterations in the development of acquired MAPKi resistance in melanoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr A004.

Abstract B044: Fragmentomic features of cell-free DNA predict late-stage melanoma treatment benefit and survival

Abstract The levels of circulating tumour DNA (ctDNA) in cancer patients are associated with response and survival outcomes. Analysis of ctDNA generally requires knowledge of tumour mutations or the application of expensive next generation targeted sequencing. Here we utilize a cutting-edge approach, combining cell-free DNA molecules (cfDNA) fragmentomics and machine learning, to infer the presence of ctDNA to predict response and survival to immune checkpoint inhibitors in stage III unresectable and IV melanoma patients. Genome libraries were constructed from cfDNA derived from 48 (discovery cohort) and 96 (validation cohort) stage III unresectable and IV melanoma patients prior to the commencement of immune-checkpoint inhibitors. The discovery cohort included any-line therapy, patients had a median age of 66, 69% were male, 33% were BRAF V600 mutant, and 88% had an ECOG of 0-1. The validation cohort included first-line therapy, patients had a median age of 69, 59% were male, 22% were BRAF V600 mutant, and 89% had an ECOG of 0-1. Genome libraries were subjected to shallow whole genome sequencing (8x) and the following metrics were calculated: tumour content prediction, aneuploidy levels, various proportions of fragments ranging from 20 bp to 320 bp, the proportion of mitochondrial DNA, and the amplitude of 10 bp size oscillations between 75-150 bp, and the Shannon diversity of trinucleotide motifs at each end of the read. Non-penalized logistic modelling was used to predict clinical benefit, and the resulting logistic model was transformed into a “white-box” model. The white-box model was applied to the cohorts and used to test progression-free and overall survival. The removal of reads with inserts <90 and >150 bp greatly improved chromosome aneuploidy detection from 19% to 31%. Logistic modelling of the fragmentomic features of cfDNA yielded an AUROC of 0.83 for prediction of clinical benefit in the discovery cohort. A cutoff was set for the fragmentomic model score and used to stratify groups for survival analysis. Patients with a low score showed significantly worse progression- free (mPFS 931 vs 286 days, HR 3.4, 95% CI 1.55-7.46, p<0.002) and overall (mOS NR vs 363 days, HR 8.1, 95% CI 2.7-24.3, p<0.001) survival. These results were replicated in the validation cohort with an AUROC of 0.78 for prediction of clinical benefit and significant associations with progression-free (mPFS 1986 vs 926 days, HR 2.33 95% CI 1.27-3.92, p=0.005) and overall (mOS NR vs 1238 days, HR 4.51 95% CI 1.7-11.96, p=0.002) survival. Fragmentomic features of plasma cfDNA enable the prediction of clinical benefit, progression-free, and overall survival in stage IV melanoma patients treated with immune-checkpoint inhibitors. Citation Format: Aaron B Beasley, Leslie Calapre, Ashleigh Stewart, Anna L Reid, Russell Diefenbach, Wei Yen Chan, Rebecca Auzins, Luisa Pinnel, Sanjeev Adhikari, Muhammad A Khattak, Peter Lau, Tarek M Meniawy, Jenny H Lee, Lydia Warburton, Michael Millward, Alexander M Menzies, Richard A Scolyer, Georgina V Long, Helen Rizos, Elin S Gray. Fragmentomic features of cell-free DNA predict late-stage melanoma treatment benefit and survival [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B044.

Melanoma Cells from Different Patients Differ in Their Sensitivity to Alpha Radiation-Mediated Killing, Sensitivity Which Correlates with Cell Nuclei Area and Double Strand Breaks

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 µm2) 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 µm2) 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 but had a similar number of DSB (6.67) and nucleus size (175.49 µm2) 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 the Intra-tumoral Diffusing alpha-emitters Radiation Therapy (Alpha DaRT) methodology may serve as an efficient treatment for human melanoma.

NCMP-07. ADVERSE NEUROLOGIC COMPLICATIONS FOLLOWING IMMUNE CHECKPOINT INHIBITORS FOR TREATMENT OF MELANOMA: COMPARATIVE ANALYSIS OF PD-1 INHIBITOR MONOTHERAPY TO COMBINATION THERAPY WITH CTLA-4 INHIBITORS

Abstract In the past decade, FDA approval of several novel immune checkpoint inhibitors (ICI) has revolutionized treatment of advanced melanoma. However, severe immune-related adverse events (irAEs) from these medications have been reported. This study examines whether PD-1/CTLA-4 inhibitor combination immunotherapy confers increased incidence of neurologic irAEs in melanoma patients compared to PD-1 inhibitor monotherapy. A retrospective, multicenter cohort study performed using TriNetX research platform identified adult patients diagnosed with melanoma. Cohort 1 (n=9,105) included melanoma patients treated with PD-1 inhibitor monotherapy (pembrolizumab or nivolumab). Cohort 2 (n=4,727) included melanoma patients treated with PD-1/CTLA-4 inhibitor combination therapy (PD-1 inhibitor + ipilimumab). Propensity Score Matching generated final cohorts (n=4,667) using covariates: gender, race, age at diagnosis, and history of nervous system disorders. Odds ratios (OR) were determined for the occurrence of neurologic irAEs at 3 years and 5 years following therapy initiation. Kaplan Meier analysis estimated survival probabilities for each irAE subtype, as defined by the 2021 Neuro irAE Disease Definition Panel. At 3 years post-diagnosis, there was increased risk of meningitis [OR: 2.8, 95% CI: (1.8, 4.2)], encephalitis [OR: 3.1, 95% CI: (1.9, 5.1)], demyelinating syndromes [OR: 2.7, 95% CI: (1.4, 5.2)], vasculitis [OR: 1.2, 95% CI: (0.5, 2.8)], peripheral neuropathy [OR: 1.3, 95% CI (1.1, 1.5)], neuromuscular junction disorders [OR: 1.1, 95% CI: (0.7, 1.8)], and myopathy [OR: 1.4, 95% CI: (1.1, 1.9)] in melanoma patients receiving combination immunotherapy compared to those receiving anti-PD-1 monotherapy. Increased incidence of neurologic irAEs corresponded with marginally lower, yet statistically significant decreases in survival probability (p<0.01), except for vasculitis (p=0.2) and neuromuscular junction irAEs (p=0.3). At 5 years following therapy initiation, these trends persisted. Melanoma patients receiving anti-PD-1/CTLA-4 combination therapies are at greater risk of neurologic irAEs than patients on anti-PD-1 monotherapy. Incidence of neurologic irAEs may confer worsened survival prognosis for these patients.

Morphological and Optical Profiling of Melanocytes and SK‐MEL‐28 Melanoma Cells Via Digital Holographic Microscopy and Quantitative Phase Imaging

AbstractMelanoma, which originates from pigment‐producing melanocytes, is an aggressive and deadly skin cancer. Despite extensive research, its mechanisms of progression and metastasis remain unclear. This study uses quantitative phase imaging via digital holographic microscopy, Principal Component Analysis (PCA), and t‐distributed Stochastic Neighbor Embedding (t‐SNE) to identify the morphological, optical, and behavioral differences between normal melanocytes and SK‐MEL‐28 melanoma cells. Our findings reveal significant differences in cell shape, size, and internal organization, with SK‐MEL‐28 cells displaying greater size variability, more polygonal shapes, and higher optical thickness. Phase shift parameters and surface roughness analyses underscore melanoma cells' uniform and predictable textures. Violin plots highlight the dynamic and varied migration of SK‐MEL‐28 cells, contrasting with the localized movement of melanocytes. Hierarchical clustering of correlation matrices provides further insights into complex morphological and optical relationships. Integrating label‐free imaging with robust analytical methods enhances understanding of melanoma's aggressive behavior, supporting targeted therapies and highlighting potential biomarkers for precise melanoma diagnostics and treatment.

TMET-30. ONCOLYTIC HSV REWIRES METABOLISM TO PROMOTE ANTITUMOR IMMUNITY THROUGH REDUCTIVE CARBOXYLATION AND FERROPTOSIS

Abstract Cancer cells autonomously rewire metabolism to meet increased bioenergetic demands. Oncolytic HSVs (oHSVs) are attenuated Herpes simplex type 1 derived viruses that lyse tumor cells releasing damage-associated molecules triggering antitumor immunity. Currently one oHSV-1 derived virus is approved for melanoma treatment in the USA and another for recurrent GBM in Japan. While several other viruses are being evaluated in clinical trials for safety and efficacy, an understanding of the impact of oHSV therapy on cancer cell metabolism is largely unexplored. A detailed understanding of how oHSV impact tumor cell metabolism and oxidative stress is important to understand the unique susceptibilities that can further be exploited to improve the therapeutic index. Here, we analyzed transcriptomic changes in tumor biopsies of recurrent high-grade glioma patients treated with oHSV. RNA-seq data obtained from pre- and post-G207 treated biopsies from phase-Ib study patients (NCT00028158) revealed enrichment in pathways related to citric acid cycle, oxidative phosphorylation, and glutamate metabolism. We confirmed these changes by RNA sequencing of oHSV-infected patient derived GBM cells. Mechanistically, oHSV hijacked cellular glucose metabolism to increase oxidative phosphorylation and modulated cellular glutamine metabolism towards reductive carboxylation and reduced free glutathione, collectively contributing to increased ROS generation. Kinome profiling revealed PKC activation upon treatment with oHSV. Increased ROS combined with reduced glutathione, and PKC activation promoted ferroptotic cell death characterized by increased lipid peroxidation and smaller, ruptured mitochondria, and contributed to immunotherapy by this treatment. IDH mutant tumors that block reductive carboxylation were resistant to oHSV-induced ferroptotic cell death and did not benefit from oHSV-induced antitumor benefit. Together, this study presents avenues to enhance antitumor immunity by oHSV therapy.

Microneedle‐Loaded Gene‐Editable Nanohybrids Engineer Cancer Cells by Telomere Stress Induction and Metabolic Interference for Enhanced Cuproptosis and Immunotherapy

AbstractCuproptosis, a novel copper‐driven cell death, offers potential for cancer therapy, yet challenges persist in targeted delivery of copper ions and therapeutic resistance management. Here, CuTG‐Cas9@PLL, a cuproptosis nano‐inducer for efficient delivery of Cu ions, 6‐Thio‐dG (6‐thio‐2′‐deoxyguanosine), and CRISPR/Cas9 to enhance cuproptosis and immunotherapy via telomere stress and metabolic interference is developed. This system, combined with microneedle patches for transdermal delivery in melanoma treatment, targets the “Warburg effect,” a key resistance mechanism, through CRISPR/Cas9‐mediated LDHA knockout, thereby sensitizing cancer cells to cuproptosis and reversing immune suppression. Moreover, 6‐Thio‐dG‐induced telomere stress not only amplifies cuproptosis via autophagy dysfunction but also boosts anti‐tumor immunity by increased immunogenicity of senescent cancer cells. This work presents a novel approach for developing efficient cuproptosis nano‐inducers and reports on the feasibility of enhancing cancer cuproptosis and anti‐tumor immunotherapy through telomere stress induction and CRISPR/Cas9‐mediated metabolic interference.

A comparison of isolated limb infusion/perfusion, immune checkpoint inhibitors, and intralesional therapy as first‐line treatment for patients with melanoma in‐transit metastases

AbstractBackgroundIsolated limb infusion and perfusion (ILI/ILP) has been a mainstay treatment for unresectable melanoma in‐transit metastases (ITM), but increased use of immune checkpoint inhibitors (ICI) and intralesional therapy (talimogene laherparepvec [TVEC]) introduced several different management options. This study compares first‐line ILI/ILP, ICI, and TVEC.MethodsRetrospective review from 12 international institutions included patients treated from 1990 to 2022 with first‐line ILI/ILP, ICI, or TVEC for unresectable melanoma ITM.ResultsA total of 551 patients were treated, with ILI/ILP (n = 356), ICI (n = 125), and TVEC (n = 70) with median follow‐up of 5.5 years. Tumor burden was highest with ILI/ILP and lowest with TVEC (p = .002). Breslow thickness was lowest with TVEC (p = .007). TVEC was mostly used in stage IIIB disease versus IIIC for ILI/ILP and ICI (p = .01). Using ICI as the reference category, TVEC had the highest odds of a complete response (CR) (odds ratio, 1.96; p = .029) and a longer local progression‐free survival (PFS) (hazard ratio [HR], 0.40; p = .003). ILI/ILP had shorter local PFS (HR, 1.72; p = .012), PFS (HR, 1.79; p < .001), distant metastasis‐free survival (DMFS) (HR, 1.75; p = .014), overall survival (HR, 1.82; p = .009), and melanoma‐specific survival (HR, 2.29; p = .004). Stage IIIB disease had longer DMFS (HR, 0.24; p < .001) compared to IIIC/D.ConclusionsTVEC as first‐line therapy for unresectable melanoma ITM was associated with superior CR rates and local PFS. Notably, TVEC was used in patients with a lower Breslow thickness, disease stage, and tumor burden. Therefore, when compared to ILI/ILP and ICI, TVEC should be considered as first‐line therapy for unresectable stage IIIB melanoma ITM with minimal tumor burden and lower Breslow thickness.

Biocompatible Naringin loaded low molecular peptide Nanogels are effective against human melanoma cells

Abstract Melanoma, a type of cancer, has the ability to metastasize and can be fatal. The lack of success in the treatment of melanoma with chemotherapeutic agents and the side effects have led to the search for new agents. Moreover, developing systems that will provide reduce side effects by using biocompatible carriers, may be beneficial. Naringin (NAR), from Citrus plants, has anticancer and anti-inflammatory properties. NAR is useful in formulations where it is used with a carrier due to its low water solubility and bioavailability with few toxicity. This study aimed to evaluate the effects of NAR-loaded peptide based Fmoc-FF nanogels on human melanoma (SK-MEL-30) cells. Characterization of NAR-loaded Fmoc-FF nanogels was carried out. The biocompatibility properties of Fmoc-FF and NAR-loaded nanogels were evaluated in mouse fibroblast (L929) cells, and their cytotoxic effects were evaluated in human melanoma (SK-MEL-30) cells by the MTT method. While the DCF-DA method was used to measure the effects on reactive oxygen species (ROS) release, the changes in oxidative stress biomarkers were examined by spectrophotometric analysis, tyrosinase enzyme activity and inflammation biomarkers were investigated by ELISA method. Comet method was used to evaluate antigenotoxic effects. It has been observed that loading NAR into Fmoc peptide gels may be effective in causing cytotoxic, genotoxic, anti-inflammatory and anti-tyrosinase effects and an increase in ROS release in melanoma cells. These results indicate that NAR-loaded Fmoc-FF gels, which have the feature of easy application to the skin, may be effective in the treatment of melanoma without causing toxic effects.

Intradermal Delivery of Cell Vaccine via Ice Microneedles for Cancer Treatment.

The living tumor cell vaccine (TCV) holds a promise for cancer immunotherapy. Microneedle arrays provide a tool to improve the immune response of vaccines by the intradermal administration in a painless manner. However, it remains challenges for microneedle arrays to deliver the living TCV intradermally. Here, an ice microneedle array delivered living TCVsis shown with sustained granulocyte-macrophage colony-stimulating factor (GM-CSF) secretion for cancer treatment. The ice microneedle array is composed of ice microneedles and a matching polymer holder, which are customized fabricated by a static optical projection lithography (SOPL) technique. The living TCV consisted ofirradiated melanoma cells transfected with nanoparticle-mediated GM-CSF plasmids. After the living TCV is readily loaded into the ice microneedle via a cryopreservation process, it couldbe efficiently delivered into the dermis by the microneedle device. Compared to the subcutaneous injection, intradermal administration led to the recruitment of more dendritic cells at the vaccination site and the increased infiltration of CD8+ T cells in the tumor. The ice microneedle array deliveres intradermal TCVssignificantly inhibited melanoma growth and effectively prevented melanoma recurrence without obvious side effects. This work demonstrates a promising TCVs for melanoma treatment, which will inspire the future of cancer immunotherapy.

Treatment of Conjunctival Melanoma Cell Lines With a Light-Activated Virus-Like Drug Conjugate Induces Immunogenic Cell Death.

Conjunctival melanoma (CJM) is a rare malignant ocular surface tumor, which often leads to local recurrences and metastases. In murine models of subcutaneous tumors, treatment with a novel virus-like drug conjugate (VDC; Bel-sar) showed a dual mechanism of action with direct tumor cell killing as well as stimulation of an antitumoral immune response. Bel-sar is currently being evaluated for the treatment of primary uveal melanoma and indeterminate nevi in a phase III clinical trial. We determined whether Bel-sar also has direct antitumor efficiency and a potential immunostimulatory capacity in CJM cells. Three human tumor-derived CJM lines were used. Bel-sar's subcellular and intracellular locations were determined with tracers. Following light activation of Bel-sar, cytotoxicity and exposure of damage-associated molecular patterns (DAMPs) were assessed. Treated tumor cells were co-cultured with THP-1 derived macrophages to assess tumor-cell phagocytosis. Bel-sar was bound and internalized by CJM cells and subsequently found in the cell membrane, lysosome, Golgi apparatus, and mitochondria. Bel-sar activation induced near complete cell death with half-maximal inhibitory concentration (IC50) values between 30 pM and 60 pM. Finally, light-activated Bel-sar enhanced exposure of DAMPs, including calreticulin, heat shock protein 90, and stimulated phagocytosis by macrophages. Treatment with a novel VDC (Bel-sar) induced pro-immunogenic cell death in all three CJM cell lines. The in vitro cytotoxicity was accompanied by exposure of DAMPs, suggesting Bel-sar is a potential treatment for CJM by a dual mechanism of action. This dual mechanism may provide a targeted and direct killing of tumor cells and induce an immune response which might decrease local recurrences and metastasis.

Injectable nanocomposite hydrogel with cascade drug release for treatment of uveal melanoma

Uveal melanoma (UM) is the most common malignant intraocular tumor with the trait of distant metastases. Currently, the standard clinical therapy results in suboptimal outcomes due to ineffective inhibition of tumor metastasis. Thus, developing novel therapeutic modalities for UM remains a critical priority. Herein, we have developed an injectable nanocomposite hydrogel (HA-DOX/LAP gel) through integrating hyaluronic acid-based drug-loaded nanoparticles into an alginate-dopamine gel, delivering the chemotherapeutic drugs, lapatinib and doxorubicin for combinational treatment of UM. HA-DOX/LAP gel is fabricated in situ by a simple injection of the mixed precursor solution into tumor sites and maintains in vivo for more than 21 days. The entrapped drug-loaded nanoparticles can gradually release from HA-DOX/LAP gel, enhancing tumor targeting and penetration, and synchronously releasing lapatinib and doxorubicin into the acidic intracellular environment to synergistically destroy UM cells. In vivo anti-tumor studies conducted in MuM-2B tumor models demonstrated that HA-DOX/LAP gel significantly impedes tumor growth, diminishes postoperative recurrence, and prolongs overall survivals of UM tumor-bearing mice through only single injection. Remarkably, the escaped drug-loaded nanoparticles effectively reduce the risk of tumor metastases. Our findings provide new insights for the development of multifunctional nanocomposite-incorporating combination therapy against UM by targeting tumor recurrence and metastases.

Dysregulation of R-loop homeostasis shapes the immunosuppressive microenvironment and induces malignant progression in melanoma.

Dysregulated R-loop homeostasis leads to DNA replication stress and genomic instability, a major driver of cancer. However, the role of R-loops in melanoma development remains unclear. We established an R-loop scoring model based on a single-cell RNA sequencing dataset and evaluated the association between the R-loop score with the melanoma immune microenvironment and treatment response. We explored the role of CENPA-mediated changes in R-loop distribution during melanoma progression by DNA/RNA immunoprecipitation and sequencing and a series of functional experiments. We found that malignant cells with high R-loop scores may be involved in melanoma progression by modulating immune evasion, metabolic reprogramming, and cancer-related pathways. A cell communication analysis revealed that high-score R-loops play an important role in altering cell-cell interactions and limiting the CD8 + cytotoxic T cell response and T cell accumulation. CENPA silencing induced changes in R-loop distribution, upregulated Hippo signaling activity, and inhibited tumor cell proliferation and migration. Moreover, the R-loop score can predict the prognosis and immunotherapy effect of melanoma patients. Our work reveals the potential molecular mechanism by which abnormal R-loops promote melanoma progression, which may help develop anticancer therapies based on R-loops or R-loop regulators.

Discovery of cloxiquine derivatives as potent HDAC inhibitors for the treatment of melanoma via activating PPARγ

Discovery of cloxiquine derivatives as potent HDAC inhibitors for the treatment of melanoma via activating PPARγ

Lnc NEAT1 facilitates the progression of melanoma by targeting the miR-152-3p/CDK6 axis: An observational study.

Long noncoding (Lnc) RNAs are novel regulators in melanoma. Lnc nuclear enriched autosomal transcript 1 (NEAT1) was reportedly upregulated in melanoma; however, the functional roles and mechanisms of Lnc NEAT1 need further investigation. Therefore, we used quantitative real-time PCR to determine the mRNA levels of Lnc NEAT1, miR-152-3p, and cyclin-dependent protein kinase 6 (CDK6). The protein level of CDK6 was determined by Western blot. Cell counting kit 8 and colony formation assays were used to assess cell proliferation. Cell migration was measured by wound healing and Transwell assays. Direct binding of the indicated molecules was verified by an RNA-binding protein immunoprecipitation assay and a dual luciferase reporter assay. The results revealed that Lnc NEAT1 and CDK6 were elevated, while miR-152-3p was downregulated in melanoma. Furthermore, Lnc NEAT1 was positively correlated with CDK6 expression and negatively correlated with miR-152-3p level. Furthermore, Lnc NEAT1 facilitated proliferation, migration, and invasion of melanoma cells. The underlying mechanism is that Lnc NEAT1 serves as a sponge for miR-152-3p to suppress the inhibitory effect of miR-152-3p on CDK6. Furthermore, the miR-152-3p/ CDK6 axis was implicated in the progression of melanoma accelerated by Lnc NEAT1. Taken together, Lnc NEAT1 may promote melanoma development by serving as an endogenous sponge of miR-152-3p, increasing CDK6 expression, and identifying a new target for the treatment of melanoma.

Progress in antitumor mechanisms and applications of phenformin (Review).

Phenformin, a biguanide compound, has attracted increased attention due to its prominent antitumor activity. As a multi‑target agent, the antitumor effects of phenformin involve a wide range of factors, including inhibition of mitochondrial complex I, activation of AMP‑activated protein kinase, impact on the tumor microenvironment, suppression of cancer stem cells and others. In addition, phenformin has been shown to markedly augment the effectiveness of various clinical treatment methods, including radiotherapy, chemotherapy, targeted therapy and immunotherapy. It is noteworthy that breakthrough progress has been made in the treatment of cancer with phenformin with application in clinical trials for the treatment of melanoma. Phenformin not only reduces the lesion area of patients, but also enhances the efficacy of dalafinib/trimetinib. In the present review, the novel breakthroughs in the antitumor effects and mechanisms of phenformin were discussed. In addition, the current review focuses on the clinical development value of phenformin, striving to provide new insights into the future research direction of phenformin in the field of tumor treatment.

Enhanced Delivery and Potency of Chemotherapeutics in Melanoma Treatment via Magnetite Nanobioconjugates

Enhanced Delivery and Potency of Chemotherapeutics in Melanoma Treatment via Magnetite Nanobioconjugates

Antiproliferative and biochemical evaluation of rose extracts: impact on tumor and normal skin cells

Rose petals (Rosa L.) are rich sources of phenolic compounds, including anthocyanins. Anthocyanins and anthocyanidins are associated with multiple health benefits due to their antioxidant properties. In this study, eighteen rose cultivars were comparatively analyzed to determine their total polyphenol and flavonoid content, as well as their antioxidant activity using the 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging method. The extracts were purified using Amberlite XAD-7 and Sephadex LH-20 columns to obtain anthocyanin-rich fractions. Individual anthocyanins were separated and identified using high-performance liquid chromatography coupled with electrospray ionization mass spectrometry (HPLC-ESI-MS). The three cultivars with the highest anthocyanin content were further examined for cytotoxic effects on cell cultures at various extract concentrations (200-1000 µg/mL) using two skin cell lines: a melanoma cell line (A375) and a normal skin cell line (Hs27). The HPLC-MS analysis identified nine different anthocyanin compounds, with the total anthocyanin content in the rose cultivars varying from 12.42 to 331.95 mg of cyanidin-3-glucoside equivalent/100g of fresh weight. The total polyphenol and total flavonoid contents ranged from 289 to 2703 mg gallic acid equivalent/100g fresh weight and 102 to 603 mg catechin equivalent/100g fresh weight, respectively. Antioxidant activity ranged from 450 to 1304 µmol trolox equivalent/g fresh weight. A significant correlation was observed between antioxidant activity and the content of anthocyanins (R = 0.875, p < 0.001), flavonoids (R = 0.982, p < 0.001), and polyphenols (R = 0.991, p < 0.001). Furthermore, principal component analysis, along with dendrograms and heatmaps, illustrated the relationships among these key compounds and their association with antioxidant activity. The MTT assay showed a substantial suppression of A375 cancer skin cells, while simultaneously exhibiting cell proliferation in Hs27 normal skin cells in a concentration-dependent manner. Altogether, results suggest that the anthocyanins from these rose cultivars could be considered as a promising agent for adjuvant treatment of skin melanoma.

Cutaneous Toxicities of Advanced Treatment for Cutaneous Melanoma: A Prospective Study from a Single-Center Institution

Background/Objectives: The landscape of advanced melanoma treatments has shifted dramatically in recent years. Target therapy and immunotherapy have changed the management of patients with both metastatic (stage IV according to AJCC 8th ed.) and nodal (stage IIB/C and III) disease. As the use of novel agents has increased, so have the cutaneous toxicities associated with these medications. While most skin reactions are low-grade and can be managed conservatively with topical therapies, high-grade or life-threatening drug reactions can arise during therapy, requiring prompt dermatologic recognition and treatment. Given the survival benefit attributed to these new agents, treating skin toxicity and maintaining a patient’s quality of life is of paramount importance. Methods: We undertook a prospective, monocentric, and descriptive study in Bologna, Italy, including patients referred to the Oncologic Dermatology Unit of IRCCS AOU of Bologna who developed biopsy-proven cutaneous adverse events (AE) under treatment with immunotherapy for cutaneous melanoma with nodal (stage IIB/C, III) and metastatic (stage IV) disease from January 2016 to April 2024. Results: In 202 identified patients, 75 (37.5%) developed skin AEs. Ipilimumab was causal for 48.1% of skin AEs, followed by nivolumab (37%) and pembrolizumab (31.4%). Recorded types of skin AEs included erythematous rash, vitiligo, alopecia, lichenoid, maculopapular, acneiform, urticarial, psoriasiform, granulomatous, eczematous, and severe cutaneous AEs, such as Erythema multiforme/Stevens-Johnson syndrome and bullous autoimmune dermatoses. Most AEs were low-grade [CTCAE 1–2] (97%) and typically occurred after 10 weeks of treatment. Conclusions: This study comprehensively describes skin AEs occurring during systemic treatment with ICIs for cutaneous melanoma at a single center.

Sodium Copper Chlorophyllin: A Sustainable Bioinspired Catalyst for the Aerobic Oxidative Synthesis of Nitrogen Heterocycles and the Oxidative Cyanation of Tertiary Amines

AbstractA remarkably simple and straightforward protocol has been reported showcasing sodium copper chlorophyllin (SCC) as an eco‐friendly, bioinspired catalyst for the aerobic oxidative synthesis of pharmaceutically prevalent nitrogen‐containing heterocycles, such as benzimidazoles and quinoxalines. This reaction was performed in green solvent water, using the green oxidant, molecular oxygen. SCC displayed exceptional efficiency, congruent with the prevailing metal/non‐metal‐based catalyst regime without requiring additives. The SCC catalyst exhibited excellent recyclability upto three cycles for the benzimidazole synthesis reaction. This benign strategy was successfully applied in synthesizing a bioactive quinoxaline i. e., Tyrphostin AG1296, a promising candidate for melanoma treatment. The catalytic activity of SCC was explored for the synthesis of another privileged moiety i. e., α‐aminonitriles, via the α‐cyanation of tertiary amines under oxidative conditions. This reaction progressed with a mild, easy‐to‐use, convenient cyanide source, such as ethyl cyanoformate, and a green and attractive solvent, such as methanol, precluding acidic media. SCC catalyst was efficiently recycled upto three cycles for the α‐aminonitriles synthesis. Overall, the utility of a biodegradable, robust catalyst such as SCC, eco‐friendly solvents such as water and methanol, green oxidants such as O2, and mild reaction conditions, devoid of acidic additives, renders the present work viable for academic and industrial research.