Principles of Targeted Therapy for Melanoma

New therapies for unresectable or metastatic cutaneous eyelid and orbital melanoma

PURPOSE

Newer treatment options offer the promise of improved outcomes for metastatic and unresectable melanoma. This investigation was performed to review these modalities for cutaneous eyelid and orbital disease.

METHODS

A search for articles that were related to this subject was performed in the PubMed database, and the bibliographies of these manuscripts were reviewed to ensure capture of the appropriate literature. Data was abstracted and analyzed.

RESULTS

Historically, patients who suffer from melanoma of the ocular adnexa have fared poorly. Approaches that employ BRAF and mitogen-associated protein kinase inhibitors, immunotherapy, and novel cellular therapies improve outcomes and survival rates, although the side effect profiles of these agents are problematic. Most of the existing strategies have not explored ocular adnexal disease specifically, and treatment plans are generally adapted from the general cutaneous oncology literature.

CONCLUSIONS

Thanks to advances in our comprehension of the cellular biology of the disease, the management of unresectable and metastatic melanoma has evolved considerably over the past several years. Newer modalities will likely continue to improve survival and reduce adverse events.

Prognostic biomarkers in melanoma: a 2023 update from clinical trials in different therapeutic scenarios

INTRODUCTION

Over the past decade, significant advancements in the field of melanoma have included the introduction of a new staging system and the development of immunotherapy and targeted therapies, leading to changes in substage classification and impacting patient prognosis. Despite these strides, early detection remains paramount. The quest for dependable prognostic biomarkers is ongoing, given melanoma's unpredictable nature, especially in identifying patients at risk of relapse. Reliable biomarkers are critical for informed treatment decisions.

AREAS COVERED

This review offers a comprehensive review of prognostic biomarkers in the context of clinical trials for immunotherapy and targeted therapy. It explores different clinical scenarios, including adjuvant, metastatic, and neo-adjuvant settings. Key findings suggest that tumor mutational burden, PD-L1 expression, IFN-γ signature, and immune-related factors are promising biomarkers associated with improved treatment responses.

EXPERT OPINION

Identifying practical prognostic factors for melanoma therapy is challenging due to the tumor's heterogeneity. Promising biomarkers include tumor mutational burden (TMB), circulating tumor DNA, and those characterizing the tumor microenvironment, especially the immune component. Future research should prioritize large-scale, prospective studies to validate and standardize these biomarkers, emphasizing clinical relevance and real-world applicability. Easily accessible biomarkers have the potential to enhance the precision and effectiveness of melanoma management.

Enhanced CTLA-4 blockade anti-tumor immunity with APG-157 combination in a murine head and neck cancer

BACKGROUND

A phase I clinical study for patients with locally advanced H&N cancer with a new class of botanical drug APG-157 provided hints of potential synergy with immunotherapy. We sought to evaluate the efficacy of the combination of APG-157 and immune checkpoint inhibitors.

METHODS

CCL23, UM-SCC1 (human), and SCCVII (HPV-), MEER (HPV+) (murine) H&N cancer cell lines were utilized for in vitro and in vivo studies. We measured tumor growth by treating the mice with APG-157, anti-PD-1, and anti-CTLA-4 antibody combinations (8 groups). The tumor microenvironments were assessed by multi-color flow cytometry, immunohistochemistry, and RNA-seq analysis. Fecal microbiome was analyzed by 16S rRNA sequence.

RESULTS

Among the eight treatment groups, APG-157 + anti-CTLA-4 demonstrated the best tumor growth suppression (p = 0.0065 compared to the control), followed by anti-PD-1 + anti-CTLA-4 treatment group (p = 0.48 compared to the control). Immunophenotype showed over 30% of CD8+ T cells in APG-157 + anti-CTLA-4 group compared to 4%-5% of CD8+ T cells for the control group. Differential gene expression analysis revealed that APG-157 + anti-CTLA-4 group showed an enriched set of genes for inflammatory response and apoptotic signaling pathways. The fecal microbiome analysis showed a substantial difference of lactobacillus genus among groups, highest for APG-157 + anti-CTLA-4 treatment group. We were unable to perform correlative studies for MEER model as there was tumor growth suppression with all treatment conditions, except for the untreated control group.

CONCLUSIONS

The results indicate that APG-157 and immune checkpoint inhibitor combination treatment could potentially lead to improved tumor control.

Relatlimab: a novel drug targeting immune checkpoint LAG-3 in melanoma therapy

Relatlimab is a type of human immunoglobulin G4 monoclonal blocking antibody. It is the world's first Lymphocyte-Activation Gene-3 (LAG-3) inhibitor and the third immune checkpoint inhibitor with clinical application, following PD-1 and CTLA-4. Relatlimab can bind to the LAG-3 receptor which blocks the interaction between LAG-3 and its ligand to reduce LAG-3 pathway-mediated immunosuppression and promote T-cell proliferation, inducing tumor cell death. On 18 March 2022, the U.S. FDA approved the fixed-dose combination of relatlimab developed by Bristol Myers Squibb with nivolumab, under the brand name Opdualag for the treatment of unresectable or metastatic melanoma in adult and pediatric patients aged 12 and older. This study comprehensively describes the mechanism of action and clinical trials of relatlimab and a brief overview of immune checkpoint drugs currently used for the treatment of melanoma.

Targeted therapeutic strategies for melanoma

ABSTRACT

Melanoma accounts for a small proportion of skin cancers diagnosed each year, but it has a high degree of malignancy and rapid progression, resulting in a short survival period for patients. The incidence of melanoma continues to rise, and now melanoma accounts for 1.7% of cancer diagnoses worldwide and is the fifth most common cancer in the United States. With the development of high-throughput sequencing technologies, the understanding of the pathophysiology of melanoma had also been improved. The most common activating mutations in melanoma cells are BRAF , NRAS , and KIT mutations, which disrupt cell signaling pathways related to tumor proliferation. The progress has led to the emergence of molecularly targeted drugs, which extends the survival of patients with advanced melanoma. A large number of clinical trials have been conducted to confirm that targeted therapy for patients with advanced melanoma can improve progression-free survival and overall survival, and for stage III patients after radical tumor resection targeted therapy can reduce the recurrence of melanoma. Patients who were originally stage III or IV inoperable have the opportunity to achieve tumor radical resection after targeted therapy. This article reviewed the clinical trial data and summarized the clinical benefits and limitations of these therapies.

Analysis and prediction of 5-year survival in patients with cutaneous melanoma: a model-based period analysis

Background

The survival and prognosis of patients are significantly threatened by cutaneous melanoma (CM), which is a highly aggressive disease. It is therefore crucial to determine the most recent survival rate of CM. This study used population-based cancer registry data to examine the 5-year relative survival rate of CM in the US.

Methods

Period analysis was used to assess the relative survival rate and trends of patients with CM in the Surveillance, Epidemiology, and End Results (SEER) database during 2004-2018. And based on the data stratified by age, gender, race and subtype in the SEER database, a generalized linear model was 12established to predict the 5-year relative survival rate of CM patients from 2019 to 2023.

Results

The 5-year relative survival increased to various degrees for both total CM and CM subtypes during the observation period. The improvement was greatest for amelanotic melanoma, increasing from 69.0% to 81.5%. The 5-year overall relative survival rates of CM were 92.9%, 93.5%, and 95.6% for 2004-2008, 2009-2013, and 2014-2018, respectively. Females had a marginally higher survival rate than males for almost all subtypes, older people had lower survival rates than younger people, white patients had higher survival rates than nonwhite ones, and urban locations had higher rates of survival from CM than rural locations did. The survival rate of CM was significantly lower for distant metastasis.

Conclusion

The survival rate of patients with CM gradually improved overall during 2004-2018. With the predicted survival rate of 96.7% for 2019-2023, this trend will still be present. Assessing the changes experienced by patients with CM over the previous 15 years can help in predicting the future course of CM. It also provides a scientific foundation that associated departments can use to develop efficient tumor prevention and control strategies.

Clinical and molecular overview of immunotherapeutic approaches for malignant skin melanoma: Past, present and future

Traditional therapeutic approaches for malignant melanoma, have proved to be limited and/or ineffective, especially with respect to their role in improving patient survival and tumor recurrence. In this regard, immunotherapy has been demonstrated to be a promising therapeutic alternative, boosting antitumor responses through the modulation of cell signaling pathways involved in the effector mechanisms of the immune system, particularly, the so-called "immunological checkpoints". Clinical studies on the efficacy and safety of immunotherapeutic regimens, alone or in combination with other antitumor approaches, have increased dramatically in recent decades, with very encouraging results. Hence, this review will discuss the current immunotherapeutic regimens used to treat malignant melanoma, as well as the molecular and cellular mechanisms involved. In addition, current clinical studies that have investigated the use, efficacy, and adverse events of immunotherapy in melanoma will also be discussed.

Current status and perspectives of interventional clinical trials for brain metastases: analysis of ClinicalTrials.gov

BACKGROUND

The management of brain metastases (BM), the major cause of cancer morbidity and mortality, is becoming an emerging area of interest. Surgery, whole brain radiation therapy (WBRT), or stereotactic radiosurgery (SRS), have historically been the main focal treatments for BM. However, the introduction of innovative targeted- and immune-based therapies is progressively changing the paradigm of BM treatment, resulting in an increase in clinical trials investigating new therapeutic strategies.

METHODS

Using ClinicalTrials.gov, the largest clinical trial registry with over 400,000 registered trials, we performed an analysis of phase II and phase III ongoing trials evaluating different systemic therapies, radiotherapy (RT), and surgery given alone or in combination in patients with BM.

RESULTS

One hundred sixty-eight trials, 133 phase II and 35 phase III; the largest part having primarily the curative treatment of patients with BM from lung cancer, breast cancer and melanoma, were selected. One hundred sixty-three trials used systemic therapies. One hundred thirteen used tyrosine kinase inhibitors, more frequently Osimertinib, Icotinib and Pyrotinib, 50 used monoclonal antibodies, more frequently Trastuzumab, Pembrolizumab, Nivolumab, 20 used conventional chemotherapies whilst no oncological active drugs were used in 6 trials. Ninety-six trials include RT; 54 as exclusive treatment and 42 in combination with systemic therapies.

CONCLUSION

Systemic targeted- and/or immune-based therapies, combined or not with RT, are increasingly used in the routine of BM treatment. SRS is progressively replacing WBRT. All these trials intend to address multiple questions on the management of patients with BMs, including the recommended upfront treatment for different cancer histologies and the optimal timing between systemic therapies and radiation regarding brain control and neurocognitive outcome and quality of life.

BRAF and MEK Inhibitors and Their Toxicities: A Meta-Analysis

PURPOSE

This meta-analysis summarizes the incidence of treatment-related adverse events (AE) of BRAFi and MEKi.

METHODS

A systematic search of Medline/PubMed was conducted to identify suitable articles published in English up to 31 December 2021. The primary outcomes were profiles for all-grade and grade 3 or higher treatment-related AEs, and the analysis of single side effects belonging to both categories.

RESULTS

The overall incidence of treatment-related all-grade Aes was 99% for Encorafenib (95% CI: 0.97-1.00) and 97% for Trametinib (95% CI: 0.92-0.99; I² = 66%) and Binimetinib (95% CI: 0.94-0.99; I² = 0%). In combined therapies, the rate was 98% for both Vemurafenib + Cobimetinib (95% CI: 0.96-0.99; I² = 77%) and Encorafenib + Binimetinib (95% CI: 0.96-1.00). Grade 3 or higher adverse events were reported in 69% of cases for Binimetinib (95% CI: 0.50-0.84; I² = 71%), 68% for Encorafenib (95% CI: 0.61-0.74), and 72% for Vemurafenib + Cobimetinib (95% CI: 0.65-0.79; I² = 84%). The most common grade 1-2 AEs were pyrexia (43%) and fatigue (28%) for Dabrafenib + Trametinib and diarrhea for both Vemurafenib + Cobimetinib (52%) and Encorafenib + Binimetinib (34%). The most common AEs of grade 3 or higher were pyrexia, rash, and hypertension for Dabrafenib + Trametinib (6%), rash and hypertension for Encorafenib + Binimetinib (6%), and increased AST and ALT for Vemurafenib + Cobimetinib (10%).

CONCLUSIONS

Our study provides comprehensive data on treatment-related adverse events of BRAFi and MEKi combination therapies, showing related toxicity profiles to offer a helpful tool for clinicians in the choice of therapy.

Melanoma-targeted photodynamic therapy based on hypericin-loaded multifunctional P123-spermine/folate micelles

Multifunctional P123 micelle linked covalently with spermine (SM) and folic acid (FA) was developed as a drug delivery system of hypericin (HYP). The chemical structures of the modified copolymers were confirmed by spectroscopy and spectrophotometric techniques (UV-vis, FTIR, and ¹H NMR). The copolymeric micelles loading HYP were prepared by solid dispersion and characterized by UV-vis, fluorescence, dynamic light scattering (DLS), ζ potential, and transmission electron microscopy (TEM). The results provided a good level of stability for HYP-loaded P123-SM, P123-FA, and P123-SM/P123-FA in the aqueous medium. The morphology analysis showed that all copolymeric micelles are spherical. Well-defined regions of different contrast allow us to infer that SM and FA were localized on the surface of micelles, and the HYP molecules are located in the core region of micelles. The uptake potential of multifunctional P123 micelle was accessed by exposing the micellar systems loading HYP to two cell lines, B16-F10 and HaCaT. HYP-loaded P123 micelles reveal a low selectivity for melanoma cells, showing significant photodamage for HaCat cells. However, the exposition of B16-F10 cells to Hyp-loaded SM- and FA-functionalized P123 micelles under light irradiation revealed the lowest CC₅₀ values. The interpretation of these results suggested that the combination of SM and FA on P123 micelles is the main factor in enhancing the HYP uptake by melanoma cells, consequently leading to its photoinactivation.

Parenteral Nanoemulsions Loaded with Combined Immuno- and Chemo-Therapy for Melanoma Treatment

High-grade melanoma remains a major life-threatening illness despite the improvement in therapeutic control that has been achieved by means of targeted therapies and immunotherapies in recent years. This work presents a preclinical-level test of a multi-pronged approach that includes the loading of immunotherapeutic (ICOS-Fc), targeted (sorafenib), and chemotherapeutic (temozolomide) agents within Intralipid^®, which is a biocompatible nanoemulsion with a long history of safe clinical use for total parenteral nutrition. This drug combination has been shown to inhibit tumor growth and angiogenesis with the involvement of the immune system, and a key role is played by ICOS-Fc. The inhibition of tumor growth in subcutaneous melanoma mouse models has been achieved using sub-therapeutic drug doses, which is most likely the result of the nanoemulsion's targeting properties. If translated to the human setting, this approach should therefore allow therapeutic efficacy to be achieved without increasing the risk of toxic effects.

Xeroderma Pigmentosum: A Genetic Condition Skin Cancer Correlated—A Systematic Review

Background. Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder of UV radiation-induced damage repair that is characterized by photosensitivity and a propensity for developing, among many others, skin cancers at an early age. This systematic review focused on the correlation between the clinical, pathological, and genetic aspects of XP and skin cancer. Methods. A systematic review was conducted through a literature search of online databases PubMed, Cochrane Library, SciELO, and Google Scholar. Search terms were “Xeroderma pigmentosum”, “XP”, “XPC”, “Nucleotide excision repair”, “NER”, “POLH”, “Dry pigmented skin”, and “UV sensitive syndrome” meshed with the terms “Skin cancer”, “Melanoma”, and “NMSC”. Results. After 504 abstracts screening, 13 full-text articles were assessed for eligibility, and 3 of them were excluded. Ten articles were selected for qualitative assessment. Conclusions. Patients with XP usually suffer shorter lives due to skin cancer and neurodegenerative disease. Deletion/alteration of a distinct gene allele can produce different types of cancer. The XPC and XP-E variants are more likely to have skin cancer than patients in other complement groups, and the most common cause of death for these patients is skin cancer (metastatic melanoma or invasive SCC). Still, aggressive preventative measures to minimize UV radiation exposure can retard the course of the disease and improve the quality of life.

Research progress of microneedles in the treatment of melanoma

Melanoma is an aggressive malignancy deriving from melanocytes, which is characterized by high tendency of metastases and mortality rate. Current therapies for melanoma, like chemotherapy, immunotherapy and targeted therapy, have the problem of systemic exposure of drugs, which will lead to many side effects and premature degradation of drugs. The resulting low drug accumulation at the lesion limits the therapeutic effect on melanoma and makes the cure rate low. As an emerging drug delivery system, microneedles (MNs) can efficiently deliver drugs through the skin, increase the drug distribution in deeper tumor sites and minimize the leakage of therapeutic drugs into adjacent tissues, thus improving the therapeutic effect. In addition, compared with traditional drug delivery methods, MN-based drug delivery system has the advantages of simplicity, safety and little pain. So MNs can be developed for the treatment of melanoma, which can relieve the pain of patients and improve the survival rate. This review aims to introduce an update on the progress of MNs as an innovative strategy for melanoma, especially when MNs combining with different therapies against melanoma, such as chemotherapy, targeted therapy, immunotherapy, photothermal therapy (PTT), photodynamic therapy (PDT) and synergic therapy.

Outcome of Elective Checkpoint Inhibitor Discontinuation in Patients with Metastatic Melanoma Who Achieved a Complete Remission: Real-World Data

Checkpoint inhibitor therapy for metastatic melanoma has dramatically improved outcomes. Currently, 20 to 40% of treated patients achieve lengthy remissions. It is not clear whether patients in remission require ongoing therapy or if treatment can be safely discontinued. A retrospective chart review was performed of patients who underwent elective treatment discontinuation after two negative scans three months apart. Of 132 checkpoint inhibitor-treated patients, 46 achieved a complete response (34.8%) and electively discontinued therapy. The progression-free survival was 97.5% at 1 year and 94.7% at 3 years following treatment discontinuation. The median duration of follow-up was 26 months. In total, 4 of 46 individuals (8.7%) eventually relapsed (median time to relapse: 27 months). The median disease-specific survival of the entire cohort was not reached and was 100% at 4 years from the start of therapy. Two patients eventually died, one from melanoma and the other from an unrelated illness. We have identified an elective treatment discontinuation strategy that is generalizable to a variety of checkpoint inhibitor ± targeted therapy regimens. We found that most complete remissions remained durable after elective treatment discontinuation. We hypothesize that this approach could decrease potential drug toxicities, reduce the treatment-related financial burden, and improve patients’ quality of life.

TIM-3 shuttled by MV3 cells-secreted exosomes inhibits CD4+ T cell immune function and induces macrophage M2 polarization to promote the growth and metastasis of melanoma cells

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MV3-Exo inhibits CD4⁺ t cell immune function and induces M2-polarized macrophages.

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TIM-3 is upregulated in MV3 cells-secreted exosomes.

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TIM-3 inhibits CD4⁺ t cell immune function and induces M2-polarized macrophages.

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TIM-3 shuttled by MV3-Exo promotes growth and metastasis of melanoma.

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The study unveiled a protective target against metastasis of melanoma.

This study is sought to determine the physiological mechanisms by which exosomes-encapsulated TIM-3 derived from melanoma cells might mediate CD4⁺ T cell immune function and macrophage M2 polarization in melanoma. Initially, exosomes were isolated from the human skin-derived melanoma cell line MV3for analysis of TIM-3 expression pattern. Next, the exosomes sourced from MV3 cells manipulated with sh-TIM-3 were co-incubated with CD4⁺ T cells to detect CD4⁺ T cell proliferation and MV3 cell migration and invasion, to observe the macrophage M2 polarization, and to determine levels of several EMT-related factors. Finally, melanoma nude mouse models were established to study the in vivo modulatory effects of TIM-3 from MV3 cells-derived exosomes. MV3 cells-derived exosomes inhibited CD4⁺ T cell immune function and promoted macrophage M2 polarization in melanoma. Our results revealed the abundance of TIM-3 in MV3 cells-derived exosomes. Of importance, silencing of TIM-3 shuttled by MV3 cells-derived exosomes improved CD4⁺ T cell immune function and inhibited macrophage M2 polarization to attenuate the growth and metastasis of melanoma cells. Collectively, MV3 cells-derived exosomes-loaded TIM-3 suppressed CD4⁺ T cell immune function and induced macrophage M2 polarization to improve occurrence and development of melanoma, therefore providing us with a potential therapeutic target for effectively combating melanoma.

Melanoma: An update on systemic therapies

Despite advances in early detection as described in part 1 of this continuing medical education series, melanoma continues to be a large contributor to cutaneous cancer-related mortality. In a subset of patients with unresectable or metastatic disease, surgical clearance is often not possible; therefore, systemic and local therapies are considered. The second article in this series provides dermatologists with an up-to-date working knowledge of the treatment options that may be prescribed by oncologists for patients with unresectable stage III, stage IV, and recurrent melanoma.

A Novel Ferroptosis-Related lncRNA Prognostic Model and Immune Infiltration Features in Skin Cutaneous Melanoma

Background: Skin cutaneous melanoma (SKCM) is an aggressive malignant skin tumor. Ferroptosis is an iron-dependent cell death that may mobilize tumor-infiltrating immunity against cancer. The potential mechanism of long non-coding RNAs (lncRNAs) in ferroptosis in SKCM is not clear. In this study, the prognostic and treatment value of ferroptosis-related lncRNAs was explored in SKCM, and a prognostic model was established.

Methods: We first explored the mutation state of ferroptosis-related genes in SKCM samples from The Cancer Genome Atlas database. Then, we utilized consensus clustering analysis to divide the samples into three clusters based on gene expression and evaluated their immune infiltration using gene-set enrichment analysis (GSEA) ESTIMATE and single-sample gene-set enrichment analysis (ssGSEA) algorithms. In addition, we applied univariate Cox analysis to screen prognostic lncRNAs and then validated their prognostic value by Kaplan–Meier (K-M) and transcripts per kilobase million (TPM) value analyses. Finally, we constructed an 18-ferroptosis-related lncRNA prognostic model by multivariate Cox analysis, and SKCM patients were allocated into different risk groups based on the median risk score. The prognostic value of the model was evaluated by K-M and time-dependent receiver operating characteristic (ROC) analyses. Additionally, the immunophenoscore (IPS) in different risk groups was detected.

Results: The top three mutated ferroptosis genes were TP53, ACSL5, and TF. The SKCM patients in the cluster C had the highest ferroptosis-related gene expression with the richest immune infiltration. Based on the 18 prognosis-related lncRNAs, we constructed a prognostic model of SKCM patients. Patients at low risk had a better prognosis and higher IPS.

Conclusion: Our findings revealed that ferroptosis-related lncRNAs were expected to become potential biomarkers and indicators of prognosis and immunotherapy treatment targets of SKCM.

The A to I editing landscape in melanoma and its relation to clinical outcome

RNA editing refers to non-transient RNA modifications that occur after transcription and prior to translation by the ribosomes. RNA editing is more widespread in cancer cells than in non-transformed cells and is associated with tumorigenesis of various cancer tissues. However, RNA editing can also generate neo-antigens that expose tumour cells to host immunosurveillance. Global RNA editing in melanoma and its relevance to clinical outcome currently remain poorly characterized. The present study compared RNA editing as well as gene expression in tumour cell lines from melanoma patients of short or long metastasis-free survival, patients relapsing or not after immuno- and targeted therapy and tumours harbouring BRAF or NRAS mutations. Overall, our results showed that NTRK gene expression can be a marker of resistance to BRAF and MEK inhibition and gives some insights of candidate genes as potential biomarkers. In addition, this study revealed an increase in Adenosine-to-Inosine editing in Alu regions and in non-repetitive regions, including the hyperediting of the MOK and DZIP3 genes in relapsed tumour samples during targeted therapy and of the ZBTB11 gene in NRAS mutated melanoma cells. Therefore, RNA editing could be a promising tool for identifying predictive markers, tumour neoantigens and targetable pathways that could help in preventing relapses during immuno- or targeted therapies.

Targeting T-type channels in cancer: What is on and what is off?

Over the past 20 years, various studies have demonstrated a pivotal role of T-type calcium channels (TTCCs) in tumor progression. Cytotoxic effects of TTCC pharmacological blockers have been reported in vitro and in preclinical models. However, their roles in cancer physiology are only beginning to be understood. In this review, we discuss evidence for the signaling pathways and cellular processes stemming from TTCC activity, mainly inferred by inverse reasoning from pharmacological blocks and, only in a few studies, by gene silencing or channel activation. A thorough analysis indicates that drug-induced cytotoxicity is partially an off-target effect. Dissection of on/off-target activity is paramount to elucidate the physiological roles of TTCCs, and to deliver efficacious therapies suited to different cancer types and stages.

Structural Protein Analysis of Driver Gene Mutations in Conjunctival Melanoma

In recent years, there has been tremendous enthusiasm with respect to detailing the genetic basis of many neoplasms, including conjunctival melanoma (CM). We aim to analyze five proteins associated with CM, namely BRAF, NRAS, c-KIT, NF1, and PTEN. We evaluated each protein for its intrinsically disordered protein regions (IDPRs) and its protein-protein interactions (PPI) with the Predictor of Natural Disordered Protein Regions (PONDR^®) and the Search Tool for the Retrieval of Interacting Genes (STRING^®). Our PONDR^® analysis found high levels of IDPRs in all five proteins with mutations linked to CM. The highest levels of IDPRs were in BRAF (45.95%), followed by PTEN (31.76%), NF1 (22.19%), c-KIT (21.82%), and NRAS (14.81%). Our STRING analysis found that each of these five proteins had more predicted interactions then expected (p-value < 1.0 × 10⁻¹⁶). Our analysis demonstrates that the mutations linked to CM likely affected IDPRs and possibly altered their highly complex PPIs. Quantifying IDPRs in BRAF, NRAS, c-KIT, NF1, and PTEN and understanding these protein regions are important processes as IDPRs can be possible drug targets for novel targeted therapies for treating CM.

Protein tyrosine phosphatase 1B(PTP1B) promotes melanoma cells progression through Src activation

Previous studies have demonstrated that protein tyrosine phosphatase 1B (PTP1B) can promote tumor progression in breast cancer, colon cancer and prostate cancer. Additionally, PTP1B also acts as a tumor suppressor in esophageal cancer and lymphoma. These findings suggest that PTP1B functions as a double-faceted molecule in tumors. However, the role of PTP1B in malignant melanoma (MM) is still unknown. PTP1B expression in normal and melanoma tissues was evaluated by GEO analysis and immunohistochemistry. The effects of PTP1B on cell migration and invasion were evaluated in melanoma cells with up – and downregulated PTP1B expression. In this study, we initially demonstrated that the expression of PTP1B in malignant melanoma tissue is significantly higher than its expression in benign nevus tissue and indicated poor survival of malignant melanoma patients. In vitro studies have demonstrated that inhibition of PTP1B suppresses and overexpression of PTP1B promotes migration and invasion of melanoma cells. Moreover, we found that PTP1B could interact with Src via coimmunoprecipitation and dephosphorylation of the Src at Tyr530 site. Collectively, our study revealed that PTP1B can promote melanoma cell metastasis by interacting with Src and provides a theoretical basis for future applications of PTP1B inhibitors in the treatment of malignant melanoma.

Nanotechnology Addressing Cutaneous Melanoma: The Italian Landscape

Cutaneous melanoma is one of the most aggressive solid tumors, with a low survival for the metastatic stage. Currently, clinical melanoma treatments include surgery, chemotherapy, targeted therapy, immunotherapy and radiotherapy. Of note, innovative therapeutic regimens concern the administration of multitarget drugs in tandem, in order to improve therapeutic efficacy. However, also, if this drug combination is clinically relevant, the patient's response is not yet optimal. In this scenario, nanotechnology-based delivery systems can play a crucial role in the clinical treatment of advanced melanoma. In fact, their nano-features enable targeted drug delivery at a cellular level by overcoming biological barriers. Various nanomedicines have been proposed for the treatment of cutaneous melanoma, and a relevant number of them are undergoing clinical trials. In Italy, researchers are focusing on the pharmaceutical development of nanoformulations for malignant melanoma therapy. The present review reports an overview of the main melanoma-addressed nanomedicines currently under study in Italy, alongside the state of the art of melanoma therapy. Moreover, the latest Italian advances concerning the pre-clinical evaluation of nanomedicines for melanoma are described.

Loss of skeletal muscle area and fat-free mass during dabrafenib/trametinib and vemurafenib/cobimetinib treatments in patients with BRAF-mutant metastatic malignant melanoma

This study aimed to assess whether dabrafenib/trametinib and vemurafenib/cobimetinib treatments are associated with a change in skeletal muscle area (SMA) and total fat-free mass (FFM) assessed by computed tomography (CT), and to compare the efficacy and safety profile of these treatments in patients with metastatic melanoma. Thirty-one patients treated with B-Raf proto-oncogene, serine/threonine kinase/MAPK extracellular receptor kinase inhibitors were included between 2016 and 2019. Eighteen patients received dabrafenib/trametinib and remaining patients received vemurafenib/cobimetinib. CT scans were performed at baseline and at 4-6 months of follow-up to measure cross-sectional areas of SMA. FFM and skeletal muscle index (SMI) values were calculated. Of the patients, including 18 treated with dabrafenib/trametinib (58.1%) and 13 with vemurafenib/cobimetinib (41.9%); 58.1% were male, 41.9% were female and median age was 52 years. A significant decrease in SMA was observed after dabrafenib/trametinib and vemurafenib/cobimetinib treatments (P = 0.003 and P = 0.002, respectively). A significant decrease in FFM values was observed after dabrafenib/trametinib and vemurafenib/cobimetinib treatments (P = 0.003 and P = 0.002, respectively). Dose-limiting toxicity (DLT) was observed in 35.9% of the patients with sarcopenia. No significant difference was seen between the dabrafenib/trametinib and vemurafenib/cobimetinib groups in median progression-free survival (PFS) (11.9 vs. 7.3 months, respectively, P = 0.28) and in median overall survival (OS) (25.46 vs. 13.7 months, respectively, P = 0.41). Baseline sarcopenia was not significantly associated with PFS or OS (P = 0.172 and P = 0.326, respectively). We found a significant decrease in SMI values determined at 4-6 months compared to the values before treatment both in dabrafenib/trametinib and vemurafenib/cobimetinib groups. DLT was similar with both treatments. Baseline sarcopenia was not significantly associated with PFS or OS.

Novel natural inhibitors targeting B-RAF(V600E) by computational study

The aim of this research was to screen the ZINC15 database to select lead compounds and drug candidates which can inhibit B-RAF (V600E). In order to identify drugs potentially inhibited B-RAF (V600E), numerous modules of Discovery Studio 4.5 were employed. Structure-based screening using LibDock was carried out followed by ADME (absorption, distribution, metabolism, excretion) and toxicity prediction. CDOCKER was performed to demonstrate the binding affinity and mechanism between ligands and B-RAF(V600E). To evaluate whether ligand-receptor complexes were stable, molecular dynamics were employed. Two novel natural compounds (ZINC000100168592 and ZINC000049784088) from ZINC15 database were found binding to B-RAF(V600E) with more favorable interaction energy in comparison with the reference drug Vemurafenib. Also, they were predicted with less ames mutagenicity, rodent carcinogenicity, non-developmental toxic potential and tolerance to cytochrome P450 2D6 (CYP2D6). The molecular dynamics simulation analysis indicated that the compound-B-RAF(V600E) complexes had more favorable potential energy compared with Vemurafenib and they can exist in natural environments stably. The result of this study shows that ZINC000100168592 and ZINC000049784088 are ideal leading potential compounds to inhibit B-RAF(V600E). The findings of this study and these selected drug candidates greatly contributed to the medication design and improvement of B-RAF(V600E) and other proteins.

Natural Phytochemicals Derived from Gymnosperms in the Prevention and Treatment of Cancers

The incidence of various types of cancer is increasing globally. To reduce the critical side effects of cancer chemotherapy, naturally derived compounds have been considered for cancer treatment. Gymnosperms are a group of plants found worldwide that have traditionally been used for therapeutic applications. Paclitaxel is a commercially available anticancer drug derived from gymnosperms. Other natural compounds with anticancer activities, such as pinostrobin and pinocembrin, are extracted from pine heartwood, and pycnogenol and enzogenol from pine bark. Gymnosperms have great potential for further study for the discovery of new anticancer compounds. This review aims to provide a rational understanding and the latest developments in potential anticancer compounds derived from gymnosperms.

The Promise of Liquid Biopsy to Predict Response to Immunotherapy in Metastatic Melanoma

Metastatic melanoma is the deadliest form of skin cancer whose incidence has been rising dramatically over the last few decades. Nowadays, the most successful approach in treating advanced melanoma is immunotherapy which encompasses the use of immune checkpoint blockers able to unleash the immune system's activity against tumor cells. Immunotherapy has dramatically changed clinical practice by contributing to increasing long term overall survival. Despite these striking therapeutic effects, the clinical benefits are strongly mitigated by innate or acquired resistance. In this context, it is of utmost importance to develop methods capable of predicting patient response to immunotherapy. To this purpose, one major step forward may be provided by measuring non-invasive biomarkers in human fluids, namely Liquid Biopsies (LBs). Several LB approaches have been developed over the last few years thanks to technological breakthroughs that have allowed to evaluate circulating components also when they are present in low abundance. The elements of this so-called "circulome" mostly encompass: tumor DNA, tumor and immune cells, soluble factors and non-coding RNAs. Here, we review the current knowledge of these molecules as predictors of response to immunotherapy in metastatic melanoma and predict that LB will soon enter into routine practice in order to guide clinical decisions for cancer immunotherapy.

The Tumor and Host Immune Signature, and the Gut Microbiota as Predictive Biomarkers for Immune Checkpoint Inhibitor Response in Melanoma Patients

There are various melanoma treatment strategies that are based on immunological responses, among which immune checkpoint inhibitors (ICI) are relatively novel form. Nowadays, anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and anti-programmed death-1 (PD-1) antibodies represent a standard treatment for metastatic melanoma. Although there are remarkable curative effects in responders to ICI therapy, up to 70% of melanoma patients show resistance to this treatment. This low response rate is caused by innate as well as acquired resistance, and some aspects of treatment resistance are still unknown. Growing evidence shows that gut microbiota and bacterial metabolites, such as short-chain fatty acids (SCFAs), affect the efficacy of immunotherapy. Various bacterial species have been indicated as potential biomarkers of anti-PD-1 or anti-CTLA-4 therapy efficacy in melanoma, next to biomarkers related to molecular and genetic tumor characteristics or the host immunological response, which are detected in patients' blood. Here, we review the current status of biomarkers of response to ICI melanoma therapies, their pre-treatment predictive values, and their utility as on-treatment monitoring tools in order to select a relevant personalized therapy on the basis of probability of the best clinical outcome.

BRAF Inhibitors: Molecular Targeting and Immunomodulatory Actions

The BRAF inhibitors vemurafenib, dabrafenib and encorafenib are used in the treatment of patients with BRAF-mutant melanoma. They selectively target BRAF kinase and thus interfere with the mitogen-activated protein kinase (MAPK) signalling pathway that regulates the proliferation and survival of melanoma cells. In addition to their molecularly targeted activity, BRAF inhibitors have immunomodulatory effects. The MAPK pathway is involved in T-cell receptor signalling, and interference in the pathway by BRAF inhibitors has beneficial effects on the tumour microenvironment and anti-tumour immune response in BRAF-mutant melanoma, including increased immune-stimulatory cytokine levels, decreased immunosuppressive cytokine levels, enhanced melanoma differentiation antigen expression and presentation of tumour antigens by HLA 1, and increased intra-tumoral T-cell infiltration and activity. These effects promote recognition of the tumour by the immune system and enhance anti-tumour T-cell responses. Combining BRAF inhibitors with MEK inhibitors provides more complete blockade of the MAPK pathway. The immunomodulatory effects of BRAF inhibition alone or in combination with MEK inhibition provide a rationale for combining these targeted therapies with immune checkpoint inhibitors. Available data support the synergy between these treatment approaches, indicating such combinations provide an additional beneficial effect on the tumour microenvironment and immune response in BRAF-mutant melanoma.

Long non-coding RNA GAS5 in human cancer

Long non-coding RNAs (lncRNAs) constitute a group of >200-nucleotide ncRNA molecules. lncRNAs regulate several cell functions, such as proliferation, apoptosis, invasion and metastasis. Meanwhile, lncRNAs are abnormally expressed in human malignancies, where they suppress or promote tumor growth. The present study focused on growth arrest-specific transcript 5 (GAS5), a well-known lncRNA that acts as a tumor suppressor but is suppressed in multiple types of cancer, including mammary carcinoma, prostate cancer, colorectal cancer, gastric cancer, melanoma, esophageal squamous cell carcinoma, lung cancer, ovarian cancer, cervical cancer, gliomas, osteosarcoma, pancreatic cancer, bladder cancer, kidney cancer, papillary thyroid carcinoma, neuroblastoma, endometrial cancer and liver cancer. Notably, GAS5 is overexpressed in liver cancer, potentially functioning as an oncogene. In the present study, the diagnostic and therapeutic roles of GAS5 in different tumors were reviewed, with a summary of the potential clinical application of the lncRNA, which may help identify novel study directions for GAS5.

Targeting Rad51 as a strategy for the treatment of melanoma cells resistant to MAPK pathway inhibition

Rad51 is an essential factor of the homologous recombination DNA repair pathway and therefore plays an important role in maintaining genomic stability. We show that RAD51 and other homologous recombination repair genes are overexpressed in metastatic melanoma cell lines and in melanoma patient samples, which correlates with reduced survival of melanoma patients. In addition, Rad51 expression in melanoma cells was regulated on a transcriptional level by the MAPK signaling pathway with Elk1 as the main downstream transcriptional effector. Most strikingly, melanoma cells which developed resistance towards MAPK inhibitors could be efficiently targeted by Rad51 inhibitors similar to their sensitive counterparts, leading to DNA damage, G2/M arrest and apoptosis. Furthermore, the treatment of MAPK inhibitor resistant cells with Rad51 inhibitors enhances the susceptibility of these cells for MAPK inhibitor treatment in vitro and in vivo. These data indicate that Rad51 plays a critical role in the survival of metastatic melanoma cells and is a promising target for the therapy of melanoma irrespective of its MAPK inhibitor resistance status.

The MNK1/2-eIF4E Axis as a Potential Therapeutic Target in Melanoma

: Melanoma is a type of skin cancer that originates in the pigment-producing cells of the body known as melanocytes. Most genetic aberrations in melanoma result in hyperactivation of the mitogen activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) pathways. We and others have shown that a specific protein synthesis pathway known as the MNK1/2-eIF4E axis is often dysregulated in cancer. The MNK1/2-eIF4E axis is a point of convergence for these signaling pathways that are commonly constitutively activated in melanoma. In this review we consider the functional implications of aberrant mRNA translation in melanoma and other malignancies. Moreover, we discuss the consequences of inhibiting the MNK1/2-eIF4E axis on the tumor and tumor-associated cells, and we provide important avenues for the utilization of this treatment modality in combination with other targeted and immune-based therapies. The past decade has seen the increased development of selective inhibitors to block the action of the MNK1/2-eIF4E pathway, which are predicted to be an effective therapy regardless of the melanoma subtype (e.g., cutaneous, acral, and mucosal).

Construction and antitumor effects of antitumor micelles with cyclic RGD-modified anlotinib

Anlotinib is a new type of small-molecule multi-target tyrosine kinase inhibitor with inhibitory effects against angiogenesis and tumor growth. An effective targeted nano-delivery system is urgently needed to effectively utilize anlotinib for the treatment of melanoma and lung metastases. In this study, an anlotinib-loaded reduction-sensitive nanomicelle, cyclic RGD peptide (cRGDyk)-anlotinib-reduction sensitive micelles (cARM), was developed as a tumor microenvironment-responsive delivery platform. The micelle carrier was formed by the self-assembly of reduction-sensitive amphiphilic copolymers DSPE-SS-PEG2k and DSPE-PEG2k-cRGDyk. The disulfide bonds in the amphiphilic block of micelles are responsive to elevated GSH in tumor cells for controlled drug release. In a B16F10 tumor-bearing mouse model, cRGDyk-anlotinib-RM (cARM) showed better tumor tissue accumulation and internalization than those for non-reduction-sensitive micelles. Therefore, this reduction-sensitive drug delivery system benefits from its specificity, prolonged blood circulation time, effective absorption by tumor cells, and rapid release of intracellular drugs and is therefore a promising strategy.