Melanoma Therapy Research Articles

Non-coding RNAs in BRAF-mutant melanoma: targets, indicators, and therapeutic potential.

Melanoma, a highly aggressive skin cancer, is often driven by BRAF mutations, such as the V600E mutation, which promotes cancer growth through the MAPK pathway and contributes to treatment resistance. Understanding the role of non-coding RNAs (ncRNAs) in these processes is crucial for developing new therapeutic strategies. This review aims to elucidate the relationship between ncRNAs and BRAF mutations in melanoma, focusing on their regulatory roles and impact on treatment resistance. We comprehensively reviewed current literature to synthesize evidence on ncRNA-mediated regulation of BRAF-mutant melanoma and their influence on therapeutic responses. Key ncRNAs, including microRNAs and long ncRNAs, were identified as significant regulators of melanoma development and therapy resistance. MicroRNAs such as miR-15/16 and miR-200 families modulate critical pathways like Wnt signaling and melanogenesis. Long ncRNAs like ANRIL and SAMMSON play roles in cell growth, invasion, and drug susceptibility. Specific ncRNAs, such as BANCR and RMEL3, intersect with the MAPK pathway, highlighting their potential as therapeutic targets or biomarkers in BRAF-mutant melanoma. Additionally, ncRNAs involved in drug resistance, such as miR-579-3p and miR-1246, target processes like autophagy and immune checkpoint regulation. This review highlights the pivotal roles of ncRNAs in regulating BRAF-mutant melanoma and their contribution to drug resistance. These findings underscore the potential of ncRNAs as biomarkers and therapeutic targets, paving the way for innovative treatments to improve outcomes for melanoma patients.

Pneumatic extrusion bioprinting-based high throughput fabrication of a melanoma 3D cell culture model for anti-cancer drug screening

The high incidence of malignant melanoma highlights the need forin vitromodels that accurately represent the tumour microenvironment, enabling developments in melanoma therapy and drug screening. Despite several advancements in 3D cell culture models, appropriate melanoma models for evaluating drug efficacy are still in high demand. The 3D pneumatic extrusion-based bioprinting technology offers numerous benefits, including the ability to achieve high-throughput capabilities. However, there is a lack of research that combines pneumatic extrusion-based bioprinting with analytical assays to enable efficient drug screening in 3D melanoma models. To address this gap, this study developed a simple and highly reproducible approach to fabricate a 3D A375 melanoma cell culture model using the pneumatic extrusion-based bioprinting technology. To optimise this method, the bioprinting parameters for producing 3D cell cultures in a 96-well plate were adjusted to improve reproducibility while maintaining the desired droplet size and a cell viability of 92.13 ± 6.02%. The cross-linking method was optimised by evaluating cell viability and proliferation of the 3D bioprinted cells in three different concentrations of calcium chloride. The lower concentration of 50 mM resulted in higher cell viability and increased cell proliferation after 9 d of incubation. The A375 cells exhibited a steadier proliferation rate in the 3D bioprinted cell cultures, and tended to aggregate into spheroids, whereas the 2D cell cultures generally formed monolayered cell sheets. In addition, we evaluated the drug responses of four different anti-cancer drugs on the A375 cells in both the 2D and 3D cell cultures. The 3D cell cultures exhibited higher levels of drug resistance in all four tested anti-cancer drugs. This method presents a simple and cost-effective method of producing and analysing 3D cell culture models that do not add additional complexity to current assays and shows considerable potential for advancing 3D cell culture models' drug efficacy evaluations.

Cubosomes and hexosomes stabilized by sorbitan monooleate as biocompatible nanoplatforms against skin metastatic human melanoma

Nanoparticles have become versatile assets in the medical field, providing notable benefits across diverse medical arenas including controlled drug delivery, imaging, and immunological assays. Among these, non-lamellar lipid nanoparticles, notably cubosomes and hexosomes, showcase remarkable biocompatibility and stability, rendering them as optimal choices for theranostic applications. Particularly, incorporating edge activators like sodium taurocholate enhances the potential of these nanoparticles for dermal and transdermal drug delivery, overcoming the stratum corneum, a first line of defense in our skin. This study reports on the formulation of monoolein-based cubosomes and hexosomes incorporating taurocholate and stabilized by Span 80 and co-encapsulating Chlorin e6 and coenzyme QH for photodynamic therapy in skin metastatic melanoma. The formulations were optimized using small-angle X-ray scattering, and cryo-transmission electron microscopy confirmed the presence of cubosomes or hexosomes, depending on the ratio between taurocholate and Span 80. Furthermore, the co-loaded nanoparticles exhibited high encapsulation efficiencies for both Ce6 and the coenzyme QH. In vitro studies on human melanoma cells (Me45) demonstrated the biocompatibility and photodynamic activity of the loaded formulations. These findings show the possibility of formulating more biocompatible cubosomes and hexosomes for photodynamic therapy in skin cancer treatment.

Advances in Melanoma: From Genetic Insights to Therapeutic Innovations.

Advances in melanoma research have unveiled critical insights into its genetic and molecular landscape, leading to significant therapeutic innovations. This review explores the intricate interplay between genetic alterations, such as mutations in BRAF, NRAS, and KIT, and melanoma pathogenesis. The MAPK and PI3K/Akt/mTOR signaling pathways are highlighted for their roles in tumor growth and resistance mechanisms. Additionally, this review delves into the impact of epigenetic modifications, including DNA methylation and histone changes, on melanoma progression. The tumor microenvironment, characterized by immune cells, stromal cells, and soluble factors, plays a pivotal role in modulating tumor behavior and treatment responses. Emerging technologies like single-cell sequencing, CRISPR-Cas9, and AI-driven diagnostics are transforming melanoma research, offering precise and personalized approaches to treatment. Immunotherapy, particularly immune checkpoint inhibitors and personalized mRNA vaccines, has revolutionized melanoma therapy by enhancing the body's immune response. Despite these advances, resistance mechanisms remain a challenge, underscoring the need for combined therapies and ongoing research to achieve durable therapeutic responses. This comprehensive overview aims to highlight the current state of melanoma research and the transformative impacts of these advancements on clinical practice.

Predictive and pharmacodynamic biomarkers for combination therapy in stage III-IV melanoma: A Simon phase II trial (NCT03999749).

222 Background: The evaluation of biomarkers that predict response and immune-related adverse events (irAEs) is crucial for optimizing melanoma treatment with Immune checkpoint inhibitors (ICIs). We report predictive and pharmacodynamic biomarkers for response and irAEs using high-dimensional flow cytometry in a phase II trial combining nivolumab (3 mg/kg), ipilimumab (1 mg/ml), and the IL-6 receptor inhibitor tocilizumab (4 mg/kg) in unresectable/advanced melanoma patients. Methods: We analyzed serum and blood from melanoma patients at baseline, weeks 7 and 37, categorized them by irAE severity and clinical response. Patients were categorized based on the severity of irAEs (grades 3-5) (TOX), the absence of toxicity or grades 1-2 irAE (NT), clinical benefit (CB), and non-clinical benefit (NCB). Immune monitoring regimen included ELISA for IL-6, gp130, IL-23, osteopontin, and Luminex oncological panel (LXSAHM-22). We employed multi-parametric flow cytometry panels to examine myeloid cells, cytotoxic T cells, and checkpoint protein expression on immune cells. We processed ~1 million PBMCs per sample using various antibodies, with data acquisition performed via Sony’s ID7000 cytometer. The data underwent quality control, normalization PBMCs per patient, concatenation, dimensionality reduction, and clustering in FlowJo. Results: Among the 70 patients administered treatment, we observed a best overall response rate of 57%. Grade 3-5 irAEs occurred in 22% of patients by week 24. Patients manifesting irAEs exhibited notably higher baseline Th17 cell counts (NT=181±18 vs. Tox=311±49, p<0.01) and CD26+ Naive CD4 T-cell populations (NT=5838±801 vs. Tox=9632±1343, p<0.04), suggesting their potential role as predictive markers for toxicity. Additionally, in vitro investigations led us to identify CD26 co-stimulation as a preliminary step in TH17 cell differentiation. Key pharmacodynamic markers included a significant elevation in Treg cells (NCB=1286±71 vs. CB=1492±95, p=0.02) and reduction in serum gp130 levels (NCB=104±5 vs. CB=83±5 ng/ml, p<0.01) at week 7 in addition to IL-6 (NCB=7.5±1.5 vs. CB=4.6±1.1 pg/ml, p<0.01) and osteopontin (NCB=95±15 vs. CB=25±3 ng/ml, p<0.01) by week 37 when compared to baseline. Conclusions: Our findings suggest that Th17 cells can serve as a toxicity biomarker for combination therapy with ipilimumab, nivolumab and tocilizumab. Circulating Treg cells and serum osteopontin have emerged as promising pharmacodynamic biomarkers. Clinical trial information: NCT03999749 .

Three-Year Analysis of Adjuvant Therapy in Postoperative Melanoma including Acral and Mucosal Subtypes.

Adjuvant therapy has improved the clinical prognosis for postoperative melanoma patients. However, the long-term efficacy of this therapy on the melanoma acral and mucosal subtypes has not been fully evaluated in previous trials. This study assessed the 3-year recurrence-free survival and overall survival of patients with melanoma, including the acral and mucosal subtypes, treated with anti-PD-1 antibody (Ab) or with the combination of the BRAF and MEK inhibitors dabrafenib and trametinib. We retrospectively analyzed both the 3-year time to relapse (TTR) and overall survival (OS) of 120 patients treated with anti-PD-1 antibody (Ab), or with the combination of dabrafenib and trametinib. The overall median TTR was 18.4 months, with a range of 0.69 to 36 months. The 3-year TTR of the acral and mucosal types was 28.1% and 38.5%, respectively. Baseline tumor thickness (TT) and acral type were associated with the TTR in subgroup analysis. Moreover, we classified 104 acral and non-acral cutaneous patients into the anti-PD-1 Abs or dabrafenib plus trametinib combined therapies cohort in multiple analyses. The acral subtype and TT were detected as important prognostic factors. In the 3-year OS, only tumor ulceration was associated with the OS in both univariate and multiple analyses. There was no significant difference in baseline or treatment-related factors of the mucosal type (p > 0.05). This study suggests that adjuvant therapy is more effective with non-acral cutaneous melanoma than either the acral or mucosal types at the 3-year TTR endpoint.

High-throughput screening identifies ibuprofen as an sEV PD-L1 inhibitor for synergistic cancer immunotherapy

Programmed death-ligand 1 (PD-L1) on tumor-derived small extracellular vesicles (sEVs) limits therapeutic effectiveness by interacting with the PD-1 receptor on host immune cells. Targeting the secretion of sEV PD-L1 has emerged as a promising strategy to enhance immunotherapy. However, the lack of small-molecule inhibitors poses a challenge for clinical translation. In this study, we developed a target and phenotype dual-driven high-throughput screening (TAP-HTS) strategy that combined virtual screening with nanoflow-based experimental verification. We identified ibuprofen (IBP) as a novel inhibitor that effectively targeted sEV PD-L1 secretion. IBP disrupted the biogenesis and secretion of PD-L1+ sEVs in tumor cells by physically interacting with a critical regulator of sEV biogenesis, hepatocyte growth factor-regulated tyrosine kinase substrate (HRS). Notably, the mechanism of action of IBP is distinct from its commonly known targets, cyclooxygenases (COX1 or COX2). Administration of IBP stimulated antitumor immunity and enhanced the efficacy of anti-PD-1 therapy in melanoma and oral squamous cell carcinoma (OSCC) mouse models. To address potential adverse effects, we further developed an IBP gel for topical application, which demonstrated remarkable therapeutic efficacy when combined with anti-PD-1 treatment. The discovery of this specific small inhibitor provides a promising avenue for establishing durable, systemic antitumor immunity.

Advancements in Melanoma Therapies: From Surgery to Immunotherapy.

Melanoma is defined as the most aggressive and deadly form of skin cancer. The treatment of melanoma depends on thedisease stage, tumor location, and extent of its spread from its point of origin. Melanoma treatment has made significantadvances, notably in the context of targeted and immunotherapies. Surgical resection is the main therapeutic option for earlystagemelanoma, and it provides favourable outcomes. With disease metastasis, systemic treatments such as immunotherapyand targeted therapy become increasingly important. The identification of mutations that lead to melanoma has influencedtreatment strategies. Targeted therapies focusing on these mutations offer improved response rates and fewer toxicities thanconventional chemotherapy. Furthermore, developing immunotherapies, including checkpoint inhibitors and tumor-infiltratinglymphocyte (TIL) therapies, has demonstrated encouraging outcomes in effectively combating cancer cells. These therapeuticagents demonstrate superior effectiveness and a more tolerable side-effect profile, improving the quality of life for patientsreceiving treatment. The future of melanoma treatment may involve a multimodal approach consisting of a combination ofsurgery, targeted therapy, and immunotherapy adapted to each patient's profile. This approach may improve survival ratesand health outcomes.

Clinical target volume design and dose in carbon-ion radiation therapy for sinonasal mucosal melanoma

Background and purposeNo guidelines exist for the clinical target volume (CTV) and radiotherapy dose in sinonasal mucosal melanoma (SNMM). Thus, we aimed to determine the carbon-ion radiotherapy (CIRT) CTV and dose for SNMM. Materials and methodsIn total, 135 patients with SNMM who received CIRT were reviewed. The relative biological effectiveness-weighted dose was 57.6 or 64 Gy in 16 fractions. CTV was classified into small CTV, which included the gross tumor and visible melanosis with a certain margin, and extended CTV, which included the tumor site and adjacent anatomical structures. Local recurrence (LR) patterns were pattern I, II, and III, defined as recurrence over the gross tumor, visible melanosis and subclinical area, which would be covered if extended CTV was applied, and outside the extended CTV, respectively. ResultsThe 5-year LR rate was 35.3 %. The prescribed dose was not a significant risk factor for pattern I LR; however, 57.6 Gy for a large tumor was insufficient for local control. Using an extended CTV was significantly associated with a lower risk of pattern II LR, and these recurrences did not occur in regions that received > 40 Gy. The 5-year pattern III LR rate was 6.4 %. ConclusionUtilizing an extended CTV in CIRT for SNMM is appropriate even for small tumors. Using a smaller CTV after an extended CTV of at least 40 Gy is recommended to reduce adverse events. Although the optimal dose for gross tumors remains unclear, the latest technology with 64 Gy showed good outcomes.

Investigating the potential mechanisms of Litsea cubeba essential oil for anti-melanoma through experimental validation, network pharmacology, and molecular docking analysis

Abstract Objectives Melanoma remains a challenge due to the lack of effective and low-toxicity treatments. Litsea cubeba essential oil (LEO), known for its tyrosinase inhibitory activity, has shown promise as an anti-melanoma compound, although robust scientific evidence is lacking. Methods We conducted GC-MS analysis to identify the major components of LEO and screened for effective components were further evaluated on A375 and HaCaT cells using the CCK-8 assay. Network pharmacology was employed to predict potential targets using PharmMapper and SwissTarget Prediction databases, with melanoma-related targets sourced from the GeneCards database. Protein–protein interaction (PPI) network was created using STRING and Cytoscape. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed through the DAVI database. Additionally, we constructed a natural product-main components-core targets-pathways-disease (NMCPD) network in Cytoscape and conducted molecular docking using PyMOL and Autodock Vina. Results GC-MS analysis revealed neral (cis-citral) and geranial (trans-citral) as the primary active components of LEO. Cell assays demonstrated that a citral mixture, in combination with LEO, effectively inhibited A375 cell growth with IC50 values of 35.94 ± 1.23 μM and 12.00 ± 0.96 μg/mL, while exhibiting minimal toxicity to HaCaT cells with IC50 values of 67.72 ± 2.96 μM and 22.32 ± 2.53 μg/mL. Screening identified10 hub targets among 190 common targets between drug and disease-related targets. KEGG pathway enrichment analysis suggested therapeutic effects of citral on melanoma by modulating signaling pathways. Molecular docking revealed strong binding affinity of neral and geranial with RXRA and ESR1, suggesting that citral, the principal LEO component, regulates multiple pathways for potential melanoma therapy. Conclusions These findings support the potential utility of LEO as a treatment for melanoma and highlight the importance of exploring tyrosinase inhibitors for the development of novel anti-melanoma drugs.

Novel gene therapy for drug-resistant melanoma: Synergistic combination of PTEN plasmid and BRD4 PROTAC-loaded lipid nanocarriers

Patients suffering from BRAF mutant melanoma have tumor recurrence within merely 7 months of treatment with a potent BRAF inhibitor (BRAFi) like vemurafenib (VEM). It has been proven that diverse molecular pathways driving BRAFi resistance converge to activation of c-Myc in melanoma. Therefore, we identified a novel combinatorial therapeutic strategy by targeting loss of PTEN tumor suppressor gene and upregulated BRD4 oncoprotein as Myc-dependent vulnerabilities of drug-resistant melanoma. Being promising therapeutic targets, we decided to concomitantly deliver PTEN plasmid and BRD4 targeted PROteolysis-TArgeting Chimera (ARV) to drug the “undruggable” c-Myc in BRAFi-resistant melanoma. Since PTEN plasmid and ARV are distinct in their physicochemical properties, we fabricated PTEN-plasmid loaded LNPs (PL-NANO) and ARV-825 loaded nanoliposomes (AL-NANO) to yield mean particle size of <100 nm and >99% encapsulation efficiency for each therapeutic payload. Combination of PL-NANO and AL-NANO displayed synergistic tumor growth inhibition and substantial apoptosis in in vitro 2D and 3D models. Importantly, simultaneous delivery of PL-NANO and AL-NANO achieved significant upregulation of PTEN expression levels and degradation of BRD4 protein to ultimately downregulate c-Myc levels in BRAFi-resistant melanoma cells. Altogether, lipid nanocarriers delivering this novel lethal cocktail stands as “one-of-a-kind” gene therapy to target “undruggable” c-Myc oncogene in BRAFi-resistant melanoma.

Adjuvant Therapy for High-Risk Stage II Melanoma: Current Paradigms in Management and Future Directions.

Melanoma is the fifth most common cancer in the United States and accounts for the majority of all skin cancer-related deaths, making it the most lethal cutaneous malignancy. Systemic adjuvant therapy for stage IIB-IV melanoma is now approved for patients who have undergone surgical resection, given the appreciable risk of recurrence and mortality in this patient population. Despite the lower stage, high-risk stage II melanoma (stage IIB/IIC) can often exhibit an even more aggressive course when compared to stage IIIA/IIIB disease, thus justifying consideration of adjuvant therapy in these patients. In this review, we highlight the current standard of practice for the treatment of stage IIB/C melanoma, with a focus on adjuvant therapies supported by published landmark clinical trials, including anti-PD-1 therapy. Notably, adjuvant therapies approved thus far in this patient population have demonstrated an improvement in recurrence-free survival, while their impact on overall survival is pending. Finally, this review highlights currently ongoing trials and future directions for research and treatment possibilities for high-risk clinical stage II melanoma.

Determinants of resistance and response to melanoma therapy.

Metastatic melanoma is among the most enigmatic advanced cancers to clinically manage despite immense progress in the way of available therapeutic options and historic decreases in the melanoma mortality rate. Most patients with metastatic melanoma treated with modern targeted therapies (for example, BRAFV600E/K inhibitors) and/or immune checkpoint blockade (for example, anti-programmed death 1 therapy) will progress, owing to profound tumor cell plasticity fueled by genetic and nongenetic mechanisms and dichotomous host microenvironmental influences. Here we discuss the determinants of tumor heterogeneity, mechanisms of therapy resistance and effective therapy regimens that hold curative promise.

Recent advances in immunotherapy and its combination therapies for advanced melanoma: a review.

The incidence of melanoma is increasing year by year and is highly malignant, with a poor prognosis. Its treatment has always attracted much attention. Among the more clinically applied immunotherapies are immune checkpoint inhibitors, bispecific antibodies, cancer vaccines, adoptive cell transfer therapy, and oncolytic virotherapy. With the continuous development of technology and trials, in addition to immune monotherapy, combinations of immunotherapy and radiotherapy have shown surprising efficacy. In this article, we review the research progress of immune monotherapy and combination therapy for advanced melanoma, with the aim of providing new ideas for the treatment strategy for advanced melanoma.

Aspirin-Fisetin Combinatorial Treatment Exerts Cytotoxic and Anti-Migratory Activities in A375 Malignant Melanoma Cells.

Background and Objectives: Malignant melanoma (MM) remains one of the most aggressive cancers worldwide, presenting a limited number of therapeutic options at present. Aspirin (ASA), a broadly used non-steroid anti-inflammatory medicine, has recently emerged as a candidate for repurposing in cancer management, due to its therapeutic potential in the treatment of several neoplasms which include MM. Fisetin (FIS) is a flavonoid phytoestrogen instilled with multispectral pharmacological activities, including a potent anti-melanoma property. The present study aimed to assess the potential improved anti-neoplastic effect resulting from the association of ASA and FIS for MM therapy. Materials and Methods: The study was conducted using the A375 cell line as an experimental model for MM. Cell viability was assessed via the MTT test. Cell morphology and confluence were evaluated using bright-field microscopy. The aspect of cell nuclei and tubulin fibers was observed through immunofluorescence staining. The irritant potential and the anti-angiogenic effect were determined on the chorioallantoic membrane of chicken fertilized eggs. Results: The main findings related herein demonstrated that the ASA 2.5 mM + FIS (5, 10, 15, and 20 µM) combination exerted a higher cytotoxicity in A375 MM cells compared to the individual compounds, which was outlined by the concentration-dependent and massive reduction in cell viability, loss of cell confluence, cell shrinkage and rounding, apoptotic-like nuclear features, constriction and disruption of tubulin filaments, increased apoptotic index, and suppressed migratory ability. ASA 2.5 mM + FIS 20 µM treatment lacked irritant potential on the chorioallantoic membrane and inhibited blood-vessel formation in ovo. Conclusion: These results stand as one of the first contributions presenting the anti-melanoma effect of the ASA + FIS combinatorial treatment.

Numerical Simulation of Thermal Therapy for Melanoma in Mice.

In recent years, the progressively escalating incidence and exceptionally high fatality rate of cutaneous melanoma have drawn the attention of numerous scholars. Magnetic induction hyperthermia, as an efficacious tumor treatment modality, has been promoted and applied in the therapy of some tumors. In this paper, the melanoma atop the mice's heads was chosen as the research subject, and a magnetic induction hyperthermia approach based on Helmholtz coils as the magnetic field excitation was investigated and designed. The influence of the electromagnetic field and thermal field on organisms was addressed through modeling by COMSOL simulation software. The results showed that the maximum values of induced electric field and magnetic induction strength in mouse tumor tissues were 63.1 V/m and 8.5621 mT, respectively, which reached the threshold value of magnetic field strength required for magnetic induction hyperthermia. The maxima of the induced electric field and magnetic induction intensity in brain tissues are, respectively, 35.828 V/m and 8.57 mT. Approximately 93% of the tumor tissue can reach 42 °C, and the maximum temperature is 44.2 °C. Within this temperature range, a large quantity of tumor cells can be successfully induced to undergo apoptosis without harming normal cells, and the therapeutic effect is favorable.

Effect of Ibuprofen as an Albumin Binder on Melanoma-Targeting Properties of 177Lu-Labeled Ibuprofen-Conjugated Alpha-Melanocyte-Stimulating Hormone Peptides.

The purpose of this study was to examine how the introduction of ibuprofen (IBU) affected tumor-targeting and biodistribution properties of 177Lu-labeled IBU-conjugated alpha-melanocyte-stimulating hormone peptides. The IBU was used as an albumin binder and conjugated to the DOTA-Lys moiety without or with a linker to yield DOTA-Lys(IBU)-GG-Nle-CycMSHhex {1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-Lys(IBU)-Gly-Gly-Nle-c[Asp-His-DPhe-Arg-Trp-Lys]-CONH2}, DOTA-Lys(Asp-IBU)-GGNle-CycMSHhex, DOTA-Lys(Asn-IBU)-GGNle-CycMSHhex, and DOTA-Lys(Dab-IBU)-GGNle-CycMSHhex peptides. Their melanocortin-receptor 1 (MC1R) binding affinities were determined on B16/F10 melanoma cells first. Then the biodistribution of 177Lu-labeled peptides was determined on B16/F10 melanoma-bearing C57 mice at 2 h postinjection to choose the lead peptide for further examination. The full biodistribution and melanoma imaging properties of 177Lu-DOTA-Lys(Asp-IBU)-GGNle-CycMSHhex were further evaluated using B16/F10 melanoma-bearing C57 mice. DOTA-Lys(IBU)-GG-Nle-CycMSHhex, DOTA-Lys(Asp-IBU)-GGNle-CycMSHhex, DOTA-Lys(Asn-IBU)-GGNle-CycMSHhex, and DOTA-Lys(Dab-IBU)-GGNle-CycMSHhex displayed the IC50 values of 1.41 ± 0.37, 1.52 ± 0.08, 0.03 ± 0.01, and 0.58 ± 0.06 nM on B16/F10 melanoma cells, respectively. 177Lu-DOTA-Lys(Asp-IBU)-GGNle-CycMSHhex exhibited the lowest liver and kidney uptake among all four designed 177Lu peptides. Therefore, 177Lu-DOTA-Lys(Asp-IBU)-GGNle-CycMSHhex was further evaluated for its full biodistribution and melanoma imaging properties. The B16/F10 melanoma uptake of 177Lu-DOTA-Lys(Asp-IBU)-GGNle-CycMSHhex was 19.5 ± 3.12, 24.12 ± 3.35, 23.85 ± 2.08, and 10.80 ± 2.89% ID/g at 0.5, 2, 4, and 24 h postinjection, respectively. Moreover, 177Lu-DOTA-Lys(Asp-IBU)-GGNle-CycMSHhex could clearly visualize the B16/F10 melanoma lesions at 2 h postinjection. The conjugation of IBU with or without a linker to GGNle-CycMSHhex affected the MC1R binding affinities of the designed peptides. The charge of the linker played a key role in the liver and kidney uptake of 177Lu-Asp-IBU, 177Lu-Asn-IBU, and 177Lu-Dab-IBU. 177Lu-Asp-IBU exhibited higher tumor/liver and tumor/kidney uptake ratios than those of 177Lu-Asn-IBU and 177Lu-Dab-IBU, underscoring its potential evaluation for melanoma therapy in the future.

Outcomes of adjuvant immune checkpoint inhibitor therapy in melanoma: a retrospective study

ABSTRACT Background Adjuvant treatment of malignant melanoma has improved the outcomes for patients. However, real-world data on efficacy and safety are limited. We investigated outcomes of melanoma patients treated with adjuvant immune checkpoint inhibitors (ICI) in the Ghent University Hospital. Methods Patients with melanoma (stage III-IV), who received at least one cycle of ICI as adjuvant treatment between 2018 and 2021 were included in this retrospective cohort study. Primary outcomes were recurrence-free (RFS) and overall survival (OS). Other outcomes of interest were relapse patterns and safety. Results 59 patients were included, with a median follow-up of 36 months. Disease recurrence or death of any cause was observed in 25/59 (42.4%) of the patients. The median RFS was 56.0 months (95%CI 36.1–75.9 months). At 48 months, RFS and OS were 55.9% and 84%, respectively. 9/23 (39%) recurrences were locoregional and 14/23 (60.9%) patients developed distant metastasis as first recurrence, including 2 (3.4%) with brain metastasis. Median time to recurrence was 9 months (range 2–56 months). 35/59 (59.3%) completed one year of adjuvant treatment, 12/59 (20.3%) stopped because of recurrence and 10/59 (16.9% because of toxicity. Immune-related adverse events wereseen in 29/59 (49.4%) patients, 10/59 (16.9%) developed grade 3-4 toxicity. Conclusion This study confirms the real-world efficacy and safety of adjuvant ICI for melanoma, achieving RFS and OS comparableto the pivotal clinical trials. About 40% of patients develop arelapse, mainly during the adjuvant treatment. The outcomes ofpatients progressing during adjuvant ICI are poor, emphasizing the need of prospective and real-world studies on optimal management after progression on (neo)adjuvant treatment.

P-363 Reproductive toxicity of new immunobiologic treatments for male patients with melanoma

Abstract Study question Do immunotherapy and targeted therapy for melanoma affect male fertility? Summary answer Immunotherapy and targeted therapy for melanoma affect sperm quality. However, the detrimental effects are only transient. Sperm quality recovers once the treatment is discontinued. What is known already Immune checkpoint inhibitors, such as anti-BRAF and anti-MEK inhibitor, are currently used in melanoma patients to modulate the immune system and promote its anti-cancer action. Since these agents do not have an anti-mitotic action, they should not cause damage to spermatogenesis. However, no specific studies on human fertility have been conducted before drug registration. In fact, based only on pre-clinical studies, fertility-lowering effect of the BRAF/MEK inhibitors cannot be excluded. Potential endocrine autoimmune-related adverse events which could alter the hypothalamic-pituitary-gonadal axis such as hypophysitis, could impair spermatogenesis. These potential harmful effects should not be overlooked when counselling patients. Study design, size, duration Male patients scheduled for immunotherapies for melanoma were prospectively recruited at National Cancer Institute in Milan, Italy, between March 2020 and April 2023. Patients were counselled by a reproductive medicine specialist and offered to cryopreserve semen before immunotherapies. A semen analysis was also proposed 6-8 months after the initiation and 6-8 months after the end of immunotherapies. The primary outcome was to compare semen variables before, during and after immunotherapies. Participants/materials, setting, methods All patients underwent therapy with Nivolumab or Dabrafenib for 12 months.Semen samples were all cryopreserved and analysed by a single biologist at the Infertility Unit of Policlinico in Milan. Data are reported as median [Interquartile range-IQR] or number (percentage). Main results and the role of chance Twenty-three men operated on for melanoma and scheduled for immunotherapy were recruited. The age of patients at cryopreservation was 33 years [29–39]. An average of 12 [10-12] sperm paillettes were cryopreserved per patient. Total sperm count and total progressive motile sperm count were 126 millions [75–246] and 90 millions [38–154], respectively. Three patients were lost to follow-up and two patients died after cryopreservation. Twelve patients (52%) returned for a semen analysis during oncological treatment. After a median time of 9 months [8-12] of immunotherapy, a reduction in all semen variables was noted, particularly in total sperm count (77 million [49-189], p = 0.05 compared to basal condition) and the total count of progressive spermatozoa (34 million [23-77], p = 0.02 compared to basal condition). No differences were observed in morphology. Ten (43%) patients returned after the end of immunotherapies. One patient died before completing the follow-up. A recovery of all sperm variables compared to the cryopreserved sample was observed. Total sperm count and total motile sperm count were 190 millions [107–320] and 79 millions [34–140], respectively (p=ns). Two patients thawed their cryopreserved semen for an IVF cycle during immunotherapy. No pregnancy was achieved. Limitations, reasons for caution Our study evaluates male fertility only in terms of semen quality. Alterations of the hypothalamic-pituitary-gonad axis, such as the increase of autoimmune phenomena, have not been studied. Furthermore, the small sample size of our study is a limit. Wider implications of the findings Our study evaluates male fertility only in terms of semen quality. Alterations of the hypothalamic-pituitary-gonad axis, such as the increase of autoimmune phenomena, have not been studied. Furthermore, the small sample size of our study is a limit. Trial registration number not applicable

Spatial transcriptomics reveals influence of microenvironment on intrinsic fates in melanoma therapy resistance.

Resistance to cancer therapy is driven by both cell-intrinsic and microenvironmental factors. Previous work has revealed that multiple resistant cell fates emerge in melanoma following treatment with targeted therapy and that, in vitro, these resistant fates are determined by the transcriptional state of individual cells prior to exposure to treatment. What remains unclear is whether these resistant fates are shared across different genetic backgrounds and how, if at all, these resistant fates interact with the tumor microenvironment. Through spatial transcriptomics and single-cell RNA sequencing, we uncovered distinct resistance programs in melanoma cells shaped by both intrinsic cellular states and the tumor microenvironment. Consensus non-negative matrix factorization revealed shared intrinsic resistance programs across different cell lines, highlighting the presence of universal and unique resistance pathways. In patient samples, we demonstrated that these resistance programs coexist within individual tumors and associate with diverse immune signatures, suggesting that the tumor microenvironment and distribution of resistant fates are closely connected. Single-cell resolution spatial transcriptomics in xenograft models revealed both intrinsically determined and extrinsically influenced resistant fates. Overall, this work demonstrates that each therapy resistant fate coexists with a distinct immune microenvironment in tumors and that, in vivo, tissue features, such as regions of necrosis, can influence which resistant fate is adopted.