The role of BRAF V600 mutation in melanoma

Identification and Targeting of Mutant Peptide Neoantigens in Cancer Immunotherapy

In recent decades, adoptive cell transfer and checkpoint blockade therapies have revolutionized immunotherapeutic approaches to cancer treatment. Advances in whole exome/genome sequencing and bioinformatic detection of tumour-specific genetic variations and the amino acid sequence alterations they induce have revealed that T cell mediated anti-tumour immunity is substantially directed at mutated peptide sequences, and the identification and therapeutic targeting of patient-specific mutated peptide antigens now represents an exciting and rapidly progressing frontier of personalized medicine in the treatment of cancer. This review outlines the historical identification and validation of mutated peptide neoantigens as a target of the immune system, and the technical development of bioinformatic and experimental strategies for detecting, confirming and prioritizing both patient-specific or "private" and frequently occurring, shared "public" neoantigenic targets. Further, we examine the range of therapeutic modalities that have demonstrated preclinical and clinical anti-tumour efficacy through specifically targeting neoantigens, including adoptive T cell transfer, checkpoint blockade and neoantigen vaccination.

Site-Selective Cross-Coupling of Polyhalogenated Arenes and Heteroarenes with Identical Halogen Groups

Methods to functionalize arenes and heteroarenes in a site-selective manner are highly sought after for rapidly constructing value-added molecules of medicinal, agrochemical, and materials interest. One effective approach is the site-selective cross-coupling of polyhalogenated arenes bearing multiple, but identical, halogen groups. Such cross-coupling reactions have proven to be incredibly effective for site-selective functionalization. However, they also present formidable challenges due to the inherent similarities in the reactivities of the halogen substituents. In this Review, we discuss strategies for site-selective cross-couplings of polyhalogenated arenes and heteroarenes bearing identical halogens, beginning first with an overview of the reaction types that are more traditional in nature, such as electronically, sterically, and directing-group-controlled processes. Following these examples is a description of emerging strategies, which includes ligand- and additive/solvent-controlled reactions as well as photochemically initiated processes.

BRAF and MEK inhibitors rechallenge as effective treatment for patients with metastatic melanoma

Despite considerable progress made in the treatment of patients with advanced melanoma, the majority of the patients treated with BRAF and mitogen-activated protein inhibitors (BRAFi and MEKi) experience a disease progression due to acquired resistance. Currently, ongoing studies explore the possibility to overcome or reverse this process. Our multicenter retrospective analysis included 51 patients with metastatic BRAF-mutated melanoma who had previously progressed on BRAFi/MEKi than had progressed on immunotherapy (anti-progression disease-1 or anti-cytotoxic T-lymphocyte-associated protein 4) and next were rechallenged with BRAFi/MEKi. Median age at BRAFi/MEKi rechallenge was 56 (range: 31-82 y/o). Median overall survival from the start of the first BRAFi/MEKi therapy and from rechallenge BRAFi/MEKi treatment was 29.7 and 9.3 months, respectively, whereas median progression-free survival was 10.5 and 5.9 months, respectively. Six-month, annual, and 2-year overall survival rates on both treatments were: 98% and 55%, 92% and 29%, and 69% and 2%, respectively. A response rate to treatment was higher in the group receiving BRAFi/MEKi for the first time as compared with the group receiving BRAFi/MEKi rechallenge and was overall response rate 72% and 27%; disease control rate 92% and 63%. Time interval between the end of the first BRAFi/MEKi treatment and the beginning of BRAFi/MEKi rechallenge did not influence median overall survival or progression-free survival. A lower toxicity rate was noted with BRAFi/MEKi rechallenge. BRAFi/MEKi rechallenge treatment remains clinically important and is associated with the lower toxicity. BRAFi/MEKi rechallenge efficacy is higher in patients who are in good performance status, with normal lactate dehydrogenase, and without brain metastases.

Precision oncology: a clinical and patient perspective

Molecular characterization of tumors has shifted cancer treatment strategies away from nonspecific cytotoxic treatment of histology-specific tumors toward targeting of actionable mutations that can be found across multiple cancer types. The development of high-throughput technologies such as next-generation sequencing, combined with decision support applications and availability of patient databases, has provided tools that optimize disease management. Precision oncology has proven success in improving outcomes and quality of life, as well as identifying and overcoming mechanisms of drug resistance and relapse. Addressing challenges that impede its use will improve matching of therapies to patients. Here we review the current status of precision oncology medicine, emphasizing its impact on patients - what they understand about precision oncology medicine and their hopes for the future.

Nephrotoxicity of cancer therapeutic drugs: Focusing on novel agents

Kidney injury caused by anticancer agents is a common problem that can interfere with and affect the dose intensity of anticancer therapy, thus restricting patient survival. Recent advances in targeted and immunotherapeutic agents have transformed the landscape of medical oncology, and these agents have been widely employed in clinical practice. While typically associated with favorable toxicity profiles, several novel anticancer drugs present distinctive nephrotoxicities. It remains urgent to closely monitor renal injuries associated with these agents, and medical practitioners should be familiar with general principles for managing nephrotoxicity associated with novel cancer drugs. This review provides an in-depth investigation of the literature and guidelines regarding the prevalence, clinical presentations, mechanisms, and management of nephrotoxicity for each drug.

The Human Melanoma Proteome Atlas-Complementing the melanoma transcriptome

The MM500 meta-study aims to establish a knowledge basis of the tumor proteome to serve as a complement to genome and transcriptome studies. Somatic mutations and their effect on the transcriptome have been extensively characterized in melanoma. However, the effects of these genetic changes on the proteomic landscape and the impact on cellular processes in melanoma remain poorly understood. In this study, the quantitative mass-spectrometry-based proteomic analysis is interfaced with pathological tumor characterization, and associated with clinical data. The melanoma proteome landscape, obtained by the analysis of 505 well-annotated melanoma tumor samples, is defined based on almost 16 000 proteins, including mutated proteoforms of driver genes. More than 50 million MS/MS spectra were analyzed, resulting in approximately 13,6 million peptide spectrum matches (PSMs). Altogether 13 176 protein-coding genes, represented by 366 172 peptides, in addition to 52 000 phosphorylation sites, and 4 400 acetylation sites were successfully annotated. This data covers 65% and 74% of the predicted and identified human proteome, respectively. A high degree of correlation (Pearson, up to 0.54) with the melanoma transcriptome of the TCGA repository, with an overlap of 12 751 gene products, was found. Mapping of the expressed proteins with quantitation, spatiotemporal localization, mutations, splice isoforms, and PTM variants was proven not to be predicted by genome sequencing alone. The melanoma tumor molecular map was complemented by analysis of blood protein expression, including data on proteins regulated after immunotherapy. By adding these key proteomic pillars, the MM500 study expands the knowledge on melanoma disease.

Current Therapeutic Strategies in BRAF-Mutant Metastatic Colorectal Cancer

Around 8–12% of patients with advanced colon rectal cancer (CRC) present with BRAF alterations, in particular V600E mutation, which is associated with right-side, poorly differentiated and mucinous type tumors. The presence of BRAF mutation (BRAF-mt) has been identified as a hallmark of poor prognosis and treatment optimization in this patient subgroup is an important goal. Currently, the standard of care is an aggressive strategy involving triplet chemotherapy and anti-VEGF agents, but new therapeutic approaches are emerging. Very promising results have been obtained with targeted therapy combinations, such as anti-BRAF agents plus anti-EGFR agents. Furthermore, around 60% of BRAF-mt patients show a strong association with high microsatellite instability (MSI-H) and immune checkpoint inhibitors could represent the new standard of care for this subgroup. The focus of this review is to summarize current strategies for BRAF-mt CRC treatment and highlight new therapeutic options.

Computer-assisted image analysis of cytological specimens clarify the correlation between nuclear size and intranuclear cytoplasmic inclusions regardless of BRAFV600E mutation in papillary thyroid carcinoma

OBJECTIVE

The morphological features of nuclei in cytological and histological specimens were compared and examined for the presence of BRAFV600E mutation and the appearance rate of intranuclear cytoplasmic inclusions (NI).

METHODS

BRAFV600E mutation was identified using a mutation-specific antibody (clone; VE1) in 103 thyroid papillary carcinoma cases at Gunma University Hospital. The nuclear area, perimeter, and roundness of the corresponding cytological specimens and haematoxylin and eosin-stained specimens were analysed using image analysis software, and the appearance rate of NI was calculated and compared.

RESULTS

BRAFV600E mutation was detected in 71 (69%) cases. The appearance rate of NI was significantly higher in the BRAFV600E mutation-positive group in cytological and histological specimens (P = .0070 and .0184, respectively). Significant differences were observed between the BRAFV600E mutation-negative and -positive groups in the average nuclear area and average nuclear perimeter in cytological specimens (P = .0137 and .0152, respectively). In addition, nuclear enlargement was correlated with the appearance rate of NI regardless of the presence of BRAFV600E mutation in cytological specimens. In the BRAFV600E mutation-negative group, the nuclear area and perimeter were significantly smaller in the lymph node metastasis-positive cases (P = .0182 and .0260, respectively).

CONCLUSION

This study found that the appearance rate of NI was positively correlated with the nuclear area and perimeter and negatively correlated with nuclear roundness in cytological specimens. Furthermore, these results were observed regardless of the existence of BRAFV600E mutation. These results have never been previously reported and clearly demonstrate the usefulness of cytological specimens in computer-assisted image analysis.

Cost-Effectiveness Analysis of Adjuvant Therapy for BRAF-Mutant Resected Stage III Melanoma in Medicare Patients

BACKGROUND

Adjuvant therapy for stage III melanoma improves several measures of patient survival. However, decisions regarding inclusion of adjuvant therapies in the formularies of public payers necessarily consider the cost-effectiveness of those treatments. The objective of this study is to evaluate the cost-effectiveness of four recently approved adjuvant therapies for BRAF-mutant stage III melanoma in the Medicare patient population.

METHODS

In this cost-effectiveness analysis, a Markov microsimulation model was used to simulate the healthcare trajectory of patients randomized to receive either first-line targeted therapy (dabrafenib-trametinib) or immunotherapy (ipilimumab, nivolumab, or pembrolizumab). The base case was a 65-year-old Medicare patient with BRAF V600E-mutant resected stage III melanoma. Possible health states included recurrence-free survival, adverse events, local recurrence, distant metastases, and death. Transition probabilities were determined from published clinical trials. Costs were estimated from reimbursement rates reported by CMS and the Red Book drug price database. Primary outcomes were costs (US$), life years, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs). Model robustness was evaluated using one-way and probabilistic sensitivity analyses.

RESULTS

Dabrafenib-trametinib provided 1.83 QALYs over no treatment and 0.23 QALYs over the most effective immunotherapy, pembrolizumab. Dabrafenib-trametinib was associated with an ICER of $95,758/QALY over no treatment and $285,863/QALY over pembrolizumab. Pembrolizumab yielded an ICER of $68,396/QALY over no treatment and dominated other immunotherapies.

CONCLUSIONS

Pembrolizumab is cost-effective at a conventional willingness-to-pay (WTP) threshold, but dabrafenib-trametinib is not. Though dabrafenib-trametinib offers incremental QALYs, optimization of drug pricing is necessary to ensure dabrafenib-trametinib is accessible at an acceptable WTP threshold.

Longitudinal assessment of B-RAF V595E levels in the peripheral cell-free tumor DNA of a 10-year-old spayed female Korean Jindo dog with unresectable metastatic urethral transitional cell carcinoma for monitoring the treatment response to a RAF inhibitor (sorafenib)

Transitional cell carcinoma (TCC) is the most common malignant tumor of the canine urinary tract. In this case study, a dog with metastatic urethral TCC was treated with sorafenib. The tumor expression levels of receptor tyrosine kinase genes, including VEGFR-1, VEGFR-2, PDGFR-α, PDGFR-β, ALK, EGFR, ErbB2, and B-RAF, were analyzed. VEGFR was overexpressed in tumor tissues compared to the normal tissues. Considering the high frequency of B-RAF mutation in canine urological tumors, the B-RAF gene was examined, and the B-RAF V595E mutation was detected in the tumor tissue. Therefore, the antitumor effect of sorafenib, a multi-tyrosine kinase inhibitor, on unresectable metastatic urethral TCC characterized by B-RAF V595E was evaluated and circulating cell-free tumor DNA (ctDNA) was assessed for monitoring the treatment response. After the initiation of oral sorafenib therapy (4 mg/kg/day escalated to 10 mg/kg/day), the dysuria was alleviated gradually, and the patient remained stable for 3 months. During that treatment period, the patient showed various levels of changes associated with B-RAF V595E mutation in ctDNA as evident from longitudinal plasma samples after initiation of sorafenib therapy. The findings of this study suggest that ctDNA may serve as a useful non-invasive tool for monitoring the treatment response to anticancer drugs.

Quality of life in patients with BRAF-mutant melanoma receiving the combination encorafenib plus binimetinib: Results from a multicentre, open-label, randomised, phase III study (COLUMBUS)

BACKGROUND

In COLUMBUS, treatment with encorafenib plus binimetinib in patients with advanced BRAF-mutant melanoma showed improved progression-free and overall survival with favourable tolerability compared to vemurafenib treatment. Here, results on health-related quality of life (HRQoL) are presented.

METHODS

COLUMBUS was a two-part, open-label, randomised, phase III study in patients with BRAF-mutant melanoma. In PART-I, 577 patients were randomised (1:1:1) to encorafenib plus binimetinib, encorafenib or vemurafenib. The primary objective was to assess progression-free survival. As a secondary objective, HRQoL was assessed by the EQ-5D, the EORTC QLQ-C30 and the FACT-M questionnaires. Furthermore, time to definitive 10% deterioration was estimated with a Kaplan-Meier analysis and differences in mean scores between groups were calculated with a mixed-effect model for repeated measures. Hospitalisation rate and the impact of hospitalisation on HRQoL were also assessed.

RESULTS

Patients receiving the combination treatment showed improvement of their FACT-M and EORTC QLQ-C30 global health status scores, compared to those receiving vemurafenib (post-baseline score differences: 3.03 [p < 0.0001] for FACT M and 5.28 [p = 0.0042] for EORTC QLQ-C30), indicative of a meaningful change in patient's status. Furthermore, a delay in the deterioration of QoL was observed in non-hospitalised patients compared to hospitalised patients (hazard ratio [95% CI]: 1.16 [0.80; 1.68] for EORTC QLQ-C30 and 1.27 [0.81; 1.99] for FACT-M) and a risk reduction of 10% deterioration, favoured the combination in both groups.

CONCLUSION

The improved efficacy of encorafenib plus binimetinib compared to vemurafenib, translates into a positive impact on the perceived health status as assessed by the HRQoL questionnaires. The study is registered with ClinicalTrials.gov, number NCT01909453 and EudraCT number 2013-001176-38.

Molecular Genetics of Conjunctival Melanoma and Prognostic Value of TERT Promoter Mutation Analysis

The aim of this study was exploration of the genetic background of conjunctival melanoma (CM) and correlation with recurrent and metastatic disease. Twenty-eight CM from the Rotterdam Ocular Melanoma Study group were collected and DNA was isolated from the formalin-fixed paraffin embedded tissue. Targeted next-generation sequencing was performed using a panel covering GNAQ, GNA11, EIF1AX, BAP1, BRAF, NRAS, c-KIT, PTEN, SF3B1, and TERT genes. Recurrences and metastasis were present in eight (29%) and nine (32%) CM cases, respectively. TERT promoter mutations were most common (54%), but BRAF (46%), NRAS (21%), BAP1 (18%), PTEN (14%), c-KIT (7%), and SF3B1 (4%) mutations were also observed. No mutations in GNAQ, GNA11, and EIF1AX were found. None of the mutations was significantly associated with recurrent disease. Presence of a TERT promoter mutation was associated with metastatic disease (p-value = 0.008). Based on our molecular findings, CM comprises a separate entity within melanoma, although there are overlapping molecular features with uveal melanoma, such as the presence of BAP1 and SF3B1 mutations. This warrants careful interpretation of molecular data, in the light of clinical findings. About three quarter of CM contain drug-targetable mutations, and TERT promoter mutations are correlated to metastatic disease in CM.

Real-World Experience with Targeted Therapy in BRAF Mutant Advanced Melanoma Patients: Results from a Multicenter Retrospective Observational Study Advanced Melanoma in Russia (Experience) (ADMIRE)

Simple Summary

Advanced melanoma is a highly aggressive disease with a poor prognosis. Recent clinical trials have shown that targeted therapy (TT) and immunotherapy (IT) lead to significant improvements in responses to treatment and the survival of advanced melanoma patients. However, little information is available in the form of real-world data on treatment patterns and clinical outcomes for patients with advanced BRAF V600 mutant melanoma. To approach this issue, we performed a retrospective study that involved 382 patients with advanced BRAF V600 mutant melanoma, who received TT in twelve medical centers. Our objectives were to evaluate clinical outcomes in real-world settings, as well as treatment patterns, adverse events, objective response rate (ORR), progression-free survival (PFS) and overall survival (OS). Considering these parameters, the results demonstrated the effectiveness of combined TT with BRAF plus MEK inhibitors in patients with brain metastases and across all lines of therapy, which was well-tolerated and manageable and showed a high safety profile.

Abstract

Clinical trials of targeted therapy (TT) and immunotherapy (IT) for highly aggressive advanced melanoma have shown marked improvements in response and survival rates. However, real-world data on treatment patterns and clinical outcomes for patients with advanced BRAF V600 mutant melanoma are ultimately scarce. The study was designed as an observational retrospective chart review study, which included 382 patients with advanced BRAF V600 mutant melanoma, who received TT in a real-world setting and were not involved in clinical trials. The data were collected from twelve medical centers in Russia. The objective response rates (ORRs) to combined BRAFi plus MEKi and to BRAFi mono-therapy were 57.4% and 39.8%, respectively. The median progression-free survival (PFS) and median overall survival (OS) were 9.2 months and 22.6 months, respectively, for the combined first-line therapy; 9.4 months and 16.1 months, respectively, for the combined second-line therapy; and 7.4 months and 17.1 months, respectively, for the combined third- or higher-line therapy. Analysis of treatment patterns demonstrated the effectiveness of the combined TT with BRAF plus MEK inhibitors in patients with brain metastases, rare types of BRAF mutations, and across lines of therapy, as well as a well-tolerated and manageable safety profile.

A Review of Epidemiology and Cancer Biology of Malignant Melanoma

Malignant melanoma is a neoplasm originating in the melanocytes in the skin. Although malignant melanoma is the third most common cutaneous cancer, it is recognized as the main cause of skin cancer-related mortality, and its incidence is rising. The natural history of malignant melanoma involves an inconsistent and insidious skin cancer with great metastatic potential. Increased ultra-violet (UV) skin exposure is undoubtedly the greatest risk factor for developing cutaneous melanoma; however, a plethora of risk factors are now recognized as causative. Moreover, modern oncology now considers melanoma proliferation a complex, multifactorial process with a combination of genetic, epigenetic, and environmental factors all known to be contributory to tumorgenesis. Herein, we wish to outline the epidemiological, molecular, and biological processes responsible for driving malignant melanoma proliferation.

Effect of hypoxia factors gene silencing on ROS production and metabolic status of A375 malignant melanoma cells

The innate response of melanocytes to exogenous or endogenous stress stimuli like extreme pH and temperature, metabolite and oxygen deficiency or a high UV dose initiates a cellular stress response. This process activates adaptive processes to minimize the negative impact of the stressor on the pigment cell. Under physiological conditions, a non-cancer cell is directed to apoptosis if the stressor persists. However, malignant melanoma cells will survive persistent stress thanks to distinct "cancerous" signaling pathways (e.g. MEK) and transcription factors that regulate the expression of so-called "survival genes" (e.g. HIF, MITF). In this survival response of cancer cells, MEK pathway directs melanoma cells to deregulate mitochondrial metabolism, to accumulate reduced species (NADH), and to centralize metabolism in the cytosol. The aim of this work was to study the effect of gene silencing in malignant melanoma A375 cells on metabolic processes in cytosol and mitochondria. Gene silencing of HIF-1α, and miR-210 in normoxia and pseudohypoxia, and analysis of its effect on MITF-M, and PDHA1 expression. Detection of cytosolic NADH by Peredox-mCherry Assay. Detection of OCR, and ECAR using Seahorse XF96. Measurement of produced O₂^•- with MitoTracker Red CMXRos. ¹H NMR analysis of metabolites present in cell suspension, and medium. By gene silencing of HIF-1α and miR-210 the expression of PDHA1 was upregulated while that of MITF-M was downregulated, yielding acceleration of mitochondrial respiratory activity and thus elimination of ROS. Hence, we detected a significantly reduced A375 cell viability, an increase in alanine, inositol, nucleotides, and other metabolites that together define apoptosis. Based on the results of measurements of mitochondrial resipiratory activity, ROS production, and changes in the metabolites obtained in cells under the observed conditions, we concluded that silencing of HIF-1α and miR-210 yields apoptosis and, ultimately, apoptotic cell death in A375 melanoma cells.

Discontinuation of BRAF/MEK-Directed Targeted Therapy after Complete Remission of Metastatic Melanoma-A Retrospective Multicenter ADOReg Study

The advent of BRAF/MEK inhibitors (BRAFi/MEKi) has significantly improved progression-free (PFS) and overall survival (OS) for patients with advanced BRAF-V600-mutant melanoma. Long-term survivors have been identified particularly among patients with a complete response (CR) to BRAF/MEK-directed targeted therapy (TT). However, it remains unclear which patients who achieved a CR maintain a durable response and whether treatment cessation might be a safe option in these patients. Therefore, this study investigated the impact of treatment cessation on the clinical course of patients with a CR upon BRAF/MEK-directed-TT. We retrospectively selected patients with BRAF-V600-mutant advanced non-resectable melanoma who had been treated with BRAFi ± MEKi therapy and achieved a CR upon treatment out of the multicentric skin cancer registry ADOReg. Data on baseline patient characteristics, duration of TT, treatment cessation, tumor progression (TP) and response to second-line treatments were collected and analyzed. Of 461 patients who received BRAF/MEK-directed TT 37 achieved a CR. TP after initial CR was observed in 22 patients (60%) mainly affecting patients who discontinued TT (n = 22/26), whereas all patients with ongoing TT (n = 11) maintained their CR. Accordingly, patients who discontinued TT had a higher risk of TP compared to patients with ongoing treatment (p < 0.001). However, our data also show that patients who received TT for more than 16 months and who discontinued TT for other reasons than TP or toxicity did not have a shorter PFS compared to patients with ongoing treatment. Response rates to second-line treatment being initiated in 21 patients, varied between 27% for immune-checkpoint inhibitors (ICI) and 60% for BRAFi/MEKi rechallenge. In summary, we identified a considerable number of patients who achieved a CR upon BRAF/MEK-directed TT in this contemporary real-world cohort of patients with BRAF-V600-mutant melanoma. Sustained PFS was not restricted to ongoing TT but was also found in patients who discontinued TT.

Combining BRAF/MEK Inhibitors with Immunotherapy in the Treatment of Metastatic Melanoma

The management and prognosis of BRAF-mutant metastatic melanoma have changed drastically following the introduction of immune checkpoint inhibitors and molecularly targeted agents. These treatment options present different mechanisms of action and toxicities but also totally distinct kinetics of their response, including a "relatively" short-lasting benefit in subsets of patients treated with BRAF/MEK inhibitors and a lower response rate in patients treated with immune checkpoint inhibitors. BRAF/MEK inhibitors, when administered prior to or concurrently with immune checkpoint inhibitors, at least transiently alter some immunosuppressive parameters of the tumor microenvironment and theoretically improve sensitivity to immunotherapy. Preclinical data from mouse models with oncogene-addicted melanoma confirmed this beneficial immune/targeted synergy and supported the clinical testing of combinations of BRAF/MEK inhibitors and immune checkpoint inhibitors to improve the activity of upfront anti-melanoma therapies. The first positive phase III results were published in 2020, and triggered the discussion about the benefits, the limitations, as well as the possible implications of combining or sequencing targeted therapies with immune checkpoint inhibitors in everyday practice. Beginning from the interplay of immune/targeted agents within the melanoma microenvironment, this review outlines available information from the retrospective experience up to the late-stage randomized evidence on combinatorial treatments. Many clinical trials are currently underway exploring open questions about optimal timing, new immune biomarkers, and eligible patient subsets for these immune/targeted regimens. Awaiting these results, decision making in the first-line setting for BRAF-mutant melanoma is still guided by the patients' characteristics and the biological aspects of melanoma.

A genome-wide atlas of co-essential modules assigns function to uncharacterized genes

A central question in the post-genomic era is how genes interact to form biological pathways. Measurements of gene dependency across hundreds of cell lines have been used to cluster genes into 'co-essential' pathways, but this approach has been limited by ubiquitous false positives. In the present study, we develop a statistical method that enables robust identification of gene co-essentiality and yields a genome-wide set of functional modules. This atlas recapitulates diverse pathways and protein complexes, and predicts the functions of 108 uncharacterized genes. Validating top predictions, we show that TMEM189 encodes plasmanylethanolamine desaturase, a key enzyme for plasmalogen synthesis. We also show that C15orf57 encodes a protein that binds the AP2 complex, localizes to clathrin-coated pits and enables efficient transferrin uptake. Finally, we provide an interactive webtool for the community to explore our results, which establish co-essentiality profiling as a powerful resource for biological pathway identification and discovery of new gene functions.

Prognostic and Predictive Biomarkers in Stage III Melanoma: Current Insights and Clinical Implications

Melanoma is one of the most aggressive skin cancers. The 5-year survival rate of stage III melanoma patients ranges from 93% (IIIA) to 32% (IIID) with a high risk of recurrence after complete surgery. The introduction of target and immune therapies has dramatically improved the overall survival, but the identification of patients with a high risk of relapse who will benefit from adjuvant therapy and the determination of the best treatment choice remain crucial. Currently, patient prognosis is based on clinico-pathological features, highlighting the urgent need of predictive and prognostic markers to improve patient management. In recent years, many groups have focused their attention on identifying molecular biomarkers with prognostic and predictive potential. In this review, we examined the main candidate biomarkers reported in the literature.

Survival of advanced melanoma patients treated with immunotherapy and targeted therapy: A real-world study

INTRODUCTION

We aimed to examine the survival outcomes plus patient and treatment characteristics of advanced melanoma patients treated with first-line immunotherapy (IT), targeted therapy (TT), and chemotherapy (CTH) and compare findings with information from pivotal trials for each therapy.

MATERIALS AND METHODS

We retrospectively reviewed the use of systematic IT, TT and CTH therapies in melanoma patients in four Queensland public hospitals. We estimated median duration of overall survival (OS) and survival rates (6 months, 1, and 2 years) using Kaplan-Meier methods. We compared our findings to those of clinical trials.

RESULTS

Five hundred three patients who met the inclusion criteria were divided into three groups based on the first-line treatment: IT 232; TT 157; and CTH 114. OS was 18 months with IT (95% CI 13, 22); 12 months with TT (95% CI 8, 15); and 5 months with CTH (95% CI 5, 6). The demographic characteristics, treatment protocols, and durations for IT and TT were generally consistent with trials but fewer patients in our study had subsequent therapy than in the trials. The OS in our study was slightly lower than the OS reported in trials.

CONCLUSION

The OS of novel cancer therapy in the real world was lower than seen in trials but is expected given these are patients who have a poorer prognosis. A future study could investigate the impact of prognostic factors on survival in the longer term. This study provides evidence that we can use routinely collected real-world data to evaluate the effectiveness of checkpoint and kinase inhibitors in patients with advanced melanoma.

The Role of Extracellular Vesicles in Mediating Resistance to Anticancer Therapies

Although advances in targeted therapies have driven great progress in cancer treatment and outcomes, drug resistance remains a major obstacle to improving patient survival. Several mechanisms are involved in developing resistance to both conventional chemotherapy and molecularly targeted therapies, including drug efflux, secondary mutations, compensatory genetic alterations occurring upstream or downstream of a drug target, oncogenic bypass, drug activation and inactivation, and DNA damage repair. Extracellular vesicles (EVs) are membrane-bound lipid bilayer vesicles that are involved in cell-cell communication and regulating biological processes. EVs derived from cancer cells play critical roles in tumor progression, metastasis, and drug resistance by delivering protein and genetic material to cells of the tumor microenvironment. Understanding the biochemical and genetic mechanisms underlying drug resistance will aid in the development of new therapeutic strategies. Herein, we review the role of EVs as mediators of drug resistance in the context of cancer.

Pulmonary metastasectomy in colorectal carcinoma

Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. It is estimated that 50% of all patients with CRC develop metastases, most commonly in the liver and the lung. Lung metastases are seen in approximately 10–15% of all patients with CRC. A large number of these patients with metastatic CRC can only receive palliative treatment due to invasion of other organs and disseminated disease. However, a subset of these patients present with potentially resectable metastases. Pulmonary metastasectomy is considered to be a potentially curative treatment for selected patients with resectable metastatic CRC. Current data suggest that patients that undergo pulmonary metastasectomy have 5-year survival rates of approximately 40%. However, the majority of data published regarding lung metastasectomy is based on small, retrospective case series. Due to this lack of prospective data, it is still unclear which subset of patients will benefit most from curative-intent surgery. Furthermore, there is also controversy regarding which prognostic and genetic factors are related to survival outcomes and whether there is a difference between open and thoracoscopic approaches in terms of overall and disease-free survival. In this review, we aim to summarize the latest data on prognostic factors and survival outcomes after pulmonary metastasectomy in patients with metastatic CRC.

Bioinformatic strategies for the analysis of genomic aberrations detected by targeted NGS panels with clinical application

Molecular profiling of tumor samples has acquired importance in cancer research, but currently also plays an important role in the clinical management of cancer patients. Rapid identification of genomic aberrations improves diagnosis, prognosis and effective therapy selection. This can be attributed mainly to the development of next-generation sequencing (NGS) methods, especially targeted DNA panels. Such panels enable a relatively inexpensive and rapid analysis of various aberrations with clinical impact specific to particular diagnoses. In this review, we discuss the experimental approaches and bioinformatic strategies available for the development of an NGS panel for a reliable analysis of selected biomarkers. Compliance with defined analytical steps is crucial to ensure accurate and reproducible results. In addition, a careful validation procedure has to be performed before the application of NGS targeted assays in routine clinical practice. With more focus on bioinformatics, we emphasize the need for thorough pipeline validation and management in relation to the particular experimental setting as an integral part of the NGS method establishment. A robust and reproducible bioinformatic analysis running on powerful machines is essential for proper detection of genomic variants in clinical settings since distinguishing between experimental noise and real biological variants is fundamental. This review summarizes state-of-the-art bioinformatic solutions for careful detection of the SNV/Indels and CNVs for targeted sequencing resulting in translation of sequencing data into clinically relevant information. Finally, we share our experience with the development of a custom targeted NGS panel for an integrated analysis of biomarkers in lymphoproliferative disorders.

Sesquiterpene Lactone Deoxyelephantopin Isolated from Elephantopus scaber and Its Derivative DETD-35 Suppress BRAFV600E Mutant Melanoma Lung Metastasis in Mice

Melanoma is a highly metastatic disease with an increasing rate of incidence worldwide. It is treatment refractory and has poor clinical prognosis; therefore, the development of new therapeutic agents for metastatic melanoma are urgently required. In this study, we created a lung-seeking A375LM5^IF4g/Luc BRAF^V600E mutant melanoma cell clone and investigated the bioefficacy of a plant sesquiterpene lactone deoxyelephantopin (DET) and its novel semi-synthetic derivative, DETD-35, in suppressing metastatic A375LM5^IF4g/Luc melanoma growth in vitro and in a xenograft mouse model. DET and DETD-35 treatment inhibited A375LM5^IF4g/Luc cell proliferation, and induced G₂/M cell-cycle arrest and apoptosis. Furthermore, A375LM5^IF4g/Luc exhibited clonogenic, metastatic and invasive abilities, and several A375LM5^IF4g/Luc metastasis markers, N-cadherin, MMP₂, vimentin and integrin α4 were significantly suppressed by treatment with either compound. Interestingly, DET- and DETD-35-induced Reactive Oxygen Species (ROS) generation and glutathione (GSH) depletion were found to be upstream events important for the in vitro activities, because exogenous GSH supplementation blunted DET and DETD-35 effects on A375LM5^IF4g/Luc cells. DET and DETD-35 also induced mitochondrial DNA mutation, superoxide production, mitochondrial bioenergetics dysfunction, and mitochondrial protein deregulation. Most importantly, DET and DETD-35 inhibited lung metastasis of A375LM5^IF4g/Luc in NOD/SCID mice through inhibiting pulmonary vascular permeability and melanoma cell (Mel-A+) proliferation, angiogenesis (VEGF+, CD31+) and EMT (N-cadherin) in the tumor microenvironment in the lungs. These findings indicate that DET and DETD-35 may be useful in the intervention of lung metastatic BRAF^V600E mutant melanoma.

FAM129B-dependent activation of NRF2 promotes an invasive phenotype in BRAF mutant melanoma cells

Incidence of melanoma continues to rise in the United States with ~100,000 new cases diagnosed in 2019. While the 5-year survival rate of melanoma is 99% when localized, the rate of survival drops to 22.5% when distant disease is detected. As such, an area of great interest is understanding the mechanisms that promote melanoma metastasis so that better potential therapeutic targets can be discovered. Herein, we demonstrate that activation of NRF2 by FAM129B contributes to increased metastatic potential of BRAF V600E mutant melanoma cells. Specifically, FAM129B induces NRF2 by competing for Kelch-like ECH-associated protein 1 (KEAP1) binding (the negative regulator of NRF2) via an ETGE motif. Furthermore, we show that phosphorylation of FAM129B plays a role in mediating the interaction between FAM129B and KEAP1, as the phosphorylation status of FAM129B dictates its subcellular localization. When phosphorylated, FAM129B is found primarily in the cytosol where it can bind to KEAP1, but upon inhibition of mitogen-activated protein kinase kinase activity, FAM129B is localized to the cell membrane and no longer interacts with KEAP1. In BRAF V600E mutant melanoma, the mitogen-activated protein kinase pathway leads to hyperphosphorylation of FAM129B, and therefore FAM129B localizes to the cytosol, binds KEAP1, and upregulates NRF2. Importantly, genetic modulation or pharmacological inhibition that results in a decrease in FAM129B protein level or its phosphorylation decreases migration and invasion of mutant melanoma in an NRF2-dependent manner. Overall, these data indicate that phosphorylation of FAM129B plays a significant role in driving the metastatic potential of BRAF V600E melanoma via upregulation of the NRF2 signaling pathway.

Expression of chondroitin sulfate proteoglycan 4 (CSPG4) in melanoma cells is downregulated upon inhibition of BRAF

Chondroitin sulfate proteoglycan 4 (CSPG4) is a multifunctional transmembrane proteoglycan involved in spreading, migration and invasion of melanoma. In addition to the activating BRAF V600E mutation, CSPG4 was shown to promote MAPK signaling by mediating the growth-factor induced activation of receptor tyrosine kinases. However, it remains elusive which factors regulate CSPG4 expression. Therefore, the aim of the present study was to examine whether BRAF and MEK inhibitors have an effect on the expression of CSPG4. We exposed a panel of BRAF-mutant CSPG4-positive or -negative melanoma cell lines to BRAF and MEK inhibitors. Protein levels of CSPG4 were analyzed by flow cytometry (FACS), immunofluorescence microscopy (IF), and western blotting. CSPG4 mRNA levels were determined by quantitative PCR (qPCR). The prolonged exposure of cells to BRAF and MEK inhibitors resulted in markedly reduced levels of the CSPG4 protein in permanent resistant melanoma cells as well as decreased levels of its mRNA. We did not observe increasing levels of CSPG4 shedding into the culture supernatants. In addition, patient-derived matched tumor samples following therapy with kinase inhibitors showed decreased numbers of CSPG4-positive cells as compared to pre-therapy tumor samples. Our results indicate that BRAF and MEK inhibition downregulates CSPG4 expression until the cells have developed permanent resistance. Our findings provide the basis for further investigation of the role of CSPG4 in the development of drug-resistance in melanoma cells.

Encorafenib with Binimetinib for the Treatment of Patients with BRAF V600 Mutation-Positive Unresectable or Metastatic Melanoma: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

As part of the Single Technology Appraisal process, the National Institute for Health and Care Excellence (NICE) invited Pierre Fabre to submit evidence for the clinical and cost-effectiveness of encorafenib with binimetinib (Enco + Bini) versus dabrafenib with trametinib (Dab + Tram) as a first-line treatment for advanced (unresectable or metastatic) BRAF V600 mutation-positive melanoma. The Liverpool Reviews and Implementation Group at the University of Liverpool was commissioned as the Evidence Review Group (ERG). This article summarises the ERG's review of the company's evidence submission (CS), and the Appraisal Committee's (AC's) final decision. The main clinical evidence in the CS was derived from the COLUMBUS trial and focused on the efficacy of Enco + Bini (encorafenib 450 mg per day plus binimetinib 45 mg twice daily) compared to vemurafenib. The company conducted network meta-analyses (NMAs) to indirectly estimate the relative effects of progression-free survival (PFS), overall survival (OS), adverse events (AEs) and health-related quality of life (HRQoL) for Enco + Bini versus Dab + Tram. None of the results from the NMAs demonstrated a statistically significant difference between the treatment regimens for any outcomes. The ERG advised caution when interpreting the results from the company's NMAs due to limitations relating to the methods. The ERG considered that use of the OS and PFS hazard ratios (HRs) generated by the company's NMAs to model the relative effectiveness of Enco + Bini versus Dab + Tram in the company model was inappropriate as these estimates were not statistically significantly different. The ERG amended the company's economic model to include estimates of equivalent efficacy, safety and HRQoL for Enco + Bini and Dab + Tram. The ERG considered use of different estimates of relative dose intensity to be inappropriate and used the same estimate for both drug combinations. The ERG also concluded that as only the prices of drug combinations were different, a cost comparison was an appropriate method of economic analysis. Using this approach (combined with confidential discounted drug prices for Enco + Bini and Dab + Tram), treatment with Enco + Bini was more cost effective than treatment with Dab + Tram. The AC raised concerns that an absence of evidence of a difference in outcomes between Enco + Bini and Dab + Tram did not constitute evidence of absence. However, as the numerical differences in outcomes generated by the company's networks were small, the AC did not have a preferred approach and considered that both the company's and the ERG's methods of incorporating outcome estimates into the economic model were suitable for decision making. The NICE AC recommended Enco + Bini as a first-line treatment for unresectable or metastatic melanoma with a BRAF V600 mutation.

The evolving paradigm of biomarker actionability: Histology-agnosticism as a spectrum, rather than a binary quality

Precision medicine is progressively revolutionizing oncology, through the identification of biomarkers predictive of treatment response in cancer patients. For three of such biomarkers, namely NTRK-fusions, microsatellite instability and high tumor mutational burden, drugs have been approved by regulatory agencies regardless of tumor histology, realizing the paradigm of histology-agnostic actionability. Several additional biomarkers are being studied in a histology-agnostic manner, and may in the future expand this list. However, most available evidence suggest that histology-agnosticism may be the extreme of a continuous spectrum of actionability, rather than a binary quality. The present review recapitulates such evidence, highlighting opportunities and challenges posed by the emergence of the spectrum of biomarker actionability in the context of a prevalently histology-based oncology.

Identification of pathways modulating vemurafenib resistance in melanoma cells via a genome-wide CRISPR/Cas9 screen

Vemurafenib is a BRAF kinase inhibitor (BRAFi) that is used to treat melanoma patients harboring the constitutively active BRAF-V600E mutation. However, after a few months of treatment patients often develop resistance to vemurafenib leading to disease progression. Sequence analysis of drug-resistant tumor cells and functional genomic screens has identified several genes that regulate vemurafenib resistance. Reactivation of mitogen-activated protein kinase (MAPK) pathway is a recurrent feature of cells that develop resistance to vemurafenib. We performed a genome-scale CRISPR-based knockout screen to identify modulators of vemurafenib resistance in melanoma cells with a highly improved CRISPR sgRNA library called Brunello. We identified 33 genes that regulate resistance to vemurafenib out of which 14 genes have not been reported before. Gene ontology enrichment analysis showed that the hit genes regulate histone modification, transcription and cell cycle. We discuss how inactivation of hit genes might confer resistance to vemurafenib and provide a framework for follow-up investigations.

BRAF Heterogeneity in Melanoma

OPINION STATEMENT

In the era of molecular targeted therapy, the accurate detection of BRAF mutation in melanoma has become increasingly important. With the advances of molecular analyses and immunohistochemistry, the presence of BRAF mutational heterogeneity in melanoma has been widely recognized. Although most patients with melanoma have a homogeneous BRAF mutation status because the BRAF mutation occurs at an early stage of melanoma development and acts as a driver gene mutation, BRAF mutational heterogeneity does exist, among different tumor sites of a single patient (intertumor heterogeneity) and/or even within a single tumor (intratumor heterogeneity). To summarize the published reports, about 10% of melanoma patients may show intertumorally discordant BRAF status and about 15% of BRAF-mutated melanomas may have intratumor BRAF heterogeneity, although the reported results vary strikingly among the studies and methods used. Considering the BRAF heterogeneity of melanoma, a single biopsy from a single tumor may not be sufficient to uncover the entire BRAF status of a patient. Multiple samples from different sites may be preferable to assess the indication of BRAF/MEK inhibitors, as recommended by the current clinical guidelines. The impact of BRAF heterogeneity on patient survival or the response to treatment with BRAF/MEK inhibitors is an interesting issue, but requires further investigation.

Association of BRAF V600E/K Mutation Status and Prior BRAF/MEK Inhibition With Pembrolizumab Outcomes in Advanced Melanoma: Pooled Analysis of 3 Clinical Trials

Importance

The optimal sequencing of immune checkpoint inhibitors and targeted therapy for BRAF V600E/K-mutant melanoma is not well established.

Objective

To assess the association of BRAF wild-type (WT) or BRAF V600E/K-mutant status and BRAF inhibitor (BRAFi) with or without MEK inhibitor (MEKi) therapy with response to pembrolizumab.

Design, Setting, and Participants

This study is a post hoc subgroup analysis of pooled data from 3 multinational, multisite studies: KEYNOTE-001 (data cutoff September 1, 2017), KEYNOTE-002 (data cutoff May 30, 2018), and KEYNOTE-006 (data cutoff December 4, 2017). Patients included in this analysis were adults with advanced melanoma and known BRAF V600E/K tumor status who had received pembrolizumab.

Interventions

Patients received pembrolizumab in dosages of 2 mg/kg every 3 weeks, 10 mg/kg every 2 weeks, or 10 mg/kg every 3 weeks.

Main Outcomes and Measures

End points were objective response rate (ORR) and progression-free survival (PFS) assessed by Response Evaluation Criteria in Solid Tumors, version 1.1, and overall survival (OS). Objective response rates, 4-year PFS, and OS rates were compared in the following patient subgroups: BRAF WT vs BRAF V600E/K-mutant melanoma and BRAF V600E/K-mutant melanoma with vs without previous treatment with BRAFi with or without MEKi therapy.

Results

The overall study population (N = 1558) included 944 men (60.6%) and 614 women (39.4%). The mean (SD) age was 60.0 years (14.0). The ORR was 38.3% (596/1558), 4-year PFS rate was 22.0%, and 4-year OS rate was 36.9%. For patients with BRAF WT (n = 1124) and BRAF V600E/K-mutant melanoma (n = 434), ORR was 39.8% (n = 447) and 34.3% (n = 149), 4-year PFS rate was 22.9% and 19.8%, and 4-year OS rate was 37.5% and 35.1%, respectively. Patients with BRAF V600E/K-mutant melanoma who had (n = 271) vs had not (n = 163) previously received BRAFi with or without MEKi therapy had baseline characteristics with worse prognosis; ORR was 28.4% (n = 77) and 44.2% (n = 72), 4-year PFS rate was 15.2% and 27.8%, and 4-year OS rate was 26.9% and 49.3%, respectively.

Conclusions and Relevance

Results of this subgroup analysis support the use of pembrolizumab for treatment of advanced melanoma regardless of BRAF V600E/K mutation status or receipt of prior BRAFi with or without MEKi therapy.

A study of pathological characteristics and BRAF V600E status in Langerhans cell histiocytosis of Vietnamese children

Background

Langerhans cell histiocytosis (LCH) is more common in children than adults and involves many organs. In children, the BRAF V600E mutation is associated with recurrent and high-risk LCH.

Methods

We collected paraffin blocks of 94 pediatric LCH patients to detect BRAF_V600E mutation by sequencing. The relationship between BRAF V600E status and clinicopathological parameters were also critically analyzed.

Results

BRAF V600E mutation exon 15 was detected in 45 cases (47.9%). Multiple systems LCH showed a significantly higher BRAF_V600E mutation rate than a single system (p=.001). No statistical significance was evident for other clinical characteristics such as age, sex, location, risk organs involvement, and CD1a expression.

Conclusions

In Vietnamese LCH children, the proportion of BRAF V600E mutational status was relatively high and related to multiple systems.

Synergistic activation of mutant TERT promoter by Sp1 and GABPA in BRAFV600E-driven human cancers

The activating TERT promoter mutations and BRAF^V600E mutation are well-established oncogenic alterations in human cancers. Coexistence of BRAF^V600E and TERT promoter mutations is frequently found in multiple cancer types, and is strongly associated with poor patient prognosis. Although the BRAF^V600E-elicited activation of ERK has been demonstrated to contribute to TERT reactivation by maintaining an active chromatin state, it still remains to be addressed how activated ERK is selectively recruited to mutant TERT promoter. Here, we report that transcription factor GABPA mediates the regulation of BRAF^V600E/MAPK signaling on TERT reactivation by selectively recruiting activated ERK to mutant TERT promoter, where activated ERK can phosphorylate Sp1, thereby resulting in HDAC1 dissociation and an active chromatin state. Meanwhile, phosphorylated Sp1 further enhances the binding of GABPA to mutant TERT promoter. Taken together, our data indicate that GABPA and Sp1 synergistically activate mutant TERT promoter, contributing to tumorigenesis and cancer progression, particularly in the BRAF^V600E-driven human cancers. Thus, our findings identify a direct mechanism that bridges two frequent oncogenic alterations together in TERT reactivation.

NECTIN4: A Novel Therapeutic Target for Melanoma

Malignant melanoma is the most common lethal skin cancer and causes death in a short time when metastasized. Although BRAF inhibitors (BRAFi) have greatly improved the prognosis of BRAF-mutated melanoma, drug resistance is a major concern even when they are combined with MEK inhibitors. Alternative treatments for BRAFi-resistant melanoma are highly anticipated. Nectin cell adhesion molecule 4 (NECTIN4) is highly expressed and associated with progression in tumors. We aimed to investigate the role of NECTIN4 in melanoma and its potency as a therapeutic target using 126 melanoma samples and BRAFi-resistant cells. Immunohistochemically, most of the clinical samples expressed NECTIN4, at least in part. NECTIN4 was highly expressed in BRAF-mutated melanoma and its high expression was associated with disease-free survival. In BRAFi-resistant melanoma cells, NECTIN4 and the PI3K/Akt pathway were upregulated, along with the acquisition of BRAFi resistance. Monomethyl auristatin E, a cytotoxic part of NECTIN4-targeted antibody-drug conjugate, was effective for BRAF-mutated or BRAFi-resistant melanoma cells. NECTIN4 inhibition increased the sensitivity of BRAFi-resistant cells to BRAFi and induced apoptosis. In conclusion, we revealed the expression and roles of NECTIN4 in melanoma. Targeted therapies against NECTIN4 can be a novel treatment strategy for melanoma, even after the acquisition of BRAFi resistance.

Comparative efficacy of dabrafenib + trametinib versus treatment options for metastatic melanoma in first-line settings

Aim: The objective was to systematically review the literature and assess the relative efficacy of agents approved in first-line settings via network meta-analysis. Materials & methods: A literature review was conducted via searching different medical databases. The eligibility criteria included Phase II or III randomized controlled trials that had enrolled treatment-naive adult patients with advanced/metastatic melanoma. Results: The network meta-analysis results suggested that dabrafenib + trametinib significantly prolongs the survival outcomes compared with the monotherapies and had comparable efficacy profile compared with encorafenib + binimetinib and cobimetinib + vemurafenib. In comparison with immunotherapies, the results varied for progression-free survival and overall survival. Conclusion: Long-term survival data of dabrafenib + trametinib establishes the combination as one of the preferred treatment options for previously untreated melanoma patients.

Results and Clinical Utilization of Foundation Medicine Molecular Tumor Profiling in Uterine and Ovarian Cancers

BACKGROUND

Recent advances in next-generation sequencing have allowed for an increase in molecular tumor profiling.

OBJECTIVE

We sought to assess the actionability and clinical utilization of molecular tumor profiling results obtained via Foundation Medicine tumor sequencing tests in uterine and ovarian cancers.

PATIENTS AND METHODS

We performed a single-institution retrospective chart review to obtain demographic and clinical information in patients with uterine and ovarian cancer whose tumors were submitted to Foundation Medicine for molecular tumor profiling over a 7-year period. Alterations identified on testing were stratified according to the OncoKB database actionability algorithm. Descriptive statistics were primarily used to analyze the data.

RESULTS

Tumors from 185 women with gynecologic cancer were submitted for molecular tumor profiling between 2013 and 2019. The majority of tests (144/185; 78%) were ordered after a diagnosis of recurrence. In 60 (32%), no actionable molecular alteration was identified. Thirteen (7%) identified an alteration that directed to a US Food and Drug Administration-approved therapy in that tumor type, while 112 (61%) had alterations with investigational or hypothetical treatment implications. In patients with any actionable finding, treatment was initiated in 27 (15%) based on these results.

CONCLUSIONS

The majority of uterine and ovarian cancers (93%) did not have molecular alterations with corresponding Food and Drug Administration-approved treatments. Even in patients with a potentially actionable alteration, gynecologic oncologists were more likely to choose an alternative therapy. Further investigation is warranted to determine which patients with uterine and ovarian cancer are most likely to benefit from molecular tumor profiling and the ideal timing of testing. The potential to identify effective therapeutic options in a minority of patients needs to be balanced with the current limited clinical applicability of these results in most cases.

Mitochondrial oxidative phosphorylation in cutaneous melanoma

The Warburg effect in tumour cells is associated with the upregulation of glycolysis to generate ATP, even under normoxic conditions and the presence of fully functioning mitochondria. However, scientific advances made over the past 15 years have reformed this perspective, demonstrating the importance of oxidative phosphorylation (OXPHOS) as well as glycolysis in malignant cells. The metabolic phenotypes in melanoma display heterogeneic dynamism (metabolic plasticity) between glycolysis and OXPHOS, conferring a survival advantage to adapt to harsh conditions and pathways of chemoresistance. Furthermore, the simultaneous upregulation of both OXPHOS and glycolysis (metabolic symbiosis) has been shown to be vital for melanoma progression. The tumour microenvironment (TME) has an essential supporting role in promoting progression, invasion and metastasis of melanoma. Mesenchymal stromal cells (MSCs) in the TME show a symbiotic relationship with melanoma, protecting tumour cells from apoptosis and conferring chemoresistance. With the significant role of OXPHOS in metabolic plasticity and symbiosis, our review outlines how mitochondrial transfer from MSCs to melanoma tumour cells plays a key role in melanoma progression and is the mechanism by which melanoma cells regain OXPHOS capacity even in the presence of mitochondrial mutations. The studies outlined in this review indicate that targeting mitochondrial trafficking is a potential novel therapeutic approach for this highly refractory disease.

Current Advancements and Novel Strategies in the Treatment of Metastatic Melanoma

Melanoma is the deadliest form of skin cancer in the world with a growing incidence in North America. Contemporary treatments for melanoma include surgical resection, chemotherapy, and radiotherapy. However, apart from resection in early melanoma, the prognosis of patients using these treatments is typically poor. In the past decade, there have been significant advancements in melanoma therapies. Immunotherapies such as ipilimumab and targeted therapies such as vemurafenib have emerged as a promising option for patients as seen in both scientific and clinical research. Furthermore, combination therapies are starting to be administered in the form of polychemotherapy, polyimmunotherapy, and biochemotherapy, of which some have shown promising outcomes in relative efficacy and safety due to their multiple targets. Alongside these treatments, new research has been conducted into the evidence-based use of natural health products (NHPs) and natural compounds (NCs) on melanoma which may provide a long-term and non-toxic form of complementary therapy. Nevertheless, there is a limited consolidation of the research conducted in emerging melanoma treatments which may be useful for researchers and clinicians. Thus, this review attempts to evaluate the therapeutic efficacy of current advancements in metastatic melanoma treatment by surveying new research into the molecular and cellular basis of treatments along with their clinical efficacy. In addition, this review aims to elucidate novel strategies that are currently being used and have the potential to be used in the future.

Model Systems for the Study of Malignant Melanoma

Since the first resection of melanoma by Hunter in 1787, efforts to treat patients with this deadly malignancy have been ongoing. Initial work to understand melanoma biology for therapeutics development began with the employment of isolated cancer cells grown in cell cultures. However, these models lack in vivo interactions with the tumor microenvironment. Melanoma cell line transplantation into suitable animals such as mice has been informative and useful for testing therapeutics as a preclinical model. Injection of freshly isolated patient melanomas into immunodeficient animals has shown the capacity to retain the genetic heterogeneity of the tumors, which is lost during the long-term culture of melanoma cells. Upon advancement of technology, genetically engineered animals have been generated to study the spontaneous development of melanomas in light of newly discovered genetic aberrations associated with melanoma formation. Culturing melanoma cells in a matrix generate tumor spheroids, providing an in vitro environment that promotes the heterogeneity commonplace with human melanoma and displaces the need for animal care facilities. Advanced 3D cultures have been created simulating the structure and cellularity of human skin to permit in vitro testing of therapeutics on melanomas expressing the same phenotype as demonstrated in vivo. This review will discuss these models and their relevance to the study of melanomagenesis, growth, metastasis, and therapy.

Identification and Characterization of a B-Raf Kinase α-Helix Critical for the Activity of MEK Kinase in MAPK Signaling

In the MAPK pathway, an oncogenic V600E mutation in B-Raf kinase causes the enzyme to be constitutively active, leading to aberrantly high phosphorylation levels of its downstream effectors, MEK and ERK kinases. The V600E mutation in B-Raf accounts for more than half of all melanomas and ∼3% of all cancers, and many drugs target the ATP binding site of the enzyme for its inhibition. Because B-Raf can develop resistance against these drugs and such drugs can induce paradoxical activation, drugs that target allosteric sites are needed. To identify other potential drug targets, we generated and kinetically characterized an active form of B-Raf^V600E expressed using a bacterial expression system. In doing so, we identified an α-helix on B-Raf, found at the B-Raf-MEK interface, that is critical for their interaction and the oncogenic activity of B-Raf^V600E. We assessed the binding between B-Raf mutants and MEK using pull downs and biolayer interferometry and assessed phosphorylation levels of MEK in vitro and in cells as well as its downstream target ERK to show that mutating certain residues on this α-helix is detrimental to binding and downstream activity. Our results suggest that this B-Raf α-helix binding site on MEK could be a site to target for drug development to treat B-Raf^V600E-induced melanomas.

Design, synthesis, and biological evaluation of novel imidazole derivatives possessing terminal sulphonamides as potential BRAFV600Einhibitors

BRAF^V600E mutation has been detected in various malignant tumours. Developing of potent BRAF^V600E inhibitors is considered a leading step in the way to cure different cancer types. In the current work, a series of 38 4-(1H-imidazol-5-yl)pyridin-2-amine derivatives was designed and synthesized using Dabrafenib as a lead compound for structural-guided optimization. The target compounds were evaluated as potential anticancer agents against NCI 60 human cancer cell lines. In 5-dose testing mode, two compounds 14h and 16e were tested to determine their IC₅₀ values over each of the 60 cell lines. The selected candidates exhibited promising activity with mean IC₅₀ values of 2.4 µM and 3.6 µM, respectively. Melanoma cancer cell lines exhibited the highest sensitivity after the treatment with the tested compounds 14h and 16e. The mean IC₅₀ values of compounds 14h and 16e against Melanoma cancer cell lines are 1.8 µM and 1.88 µM, respectively. In addition, BRAF^V600E kinase inhibitory activity was determined for each derivative. Compounds 15i, 15j, 16a, and 16d were the most potent inhibitors against BRAF^V600E with IC₅₀ 76 nM, 32 nM, 35 nM, and 68 nM. The newly developed compounds represent a therapeutically promising approach for the treating various cancer types.

Protein kinase C inhibitor anchored BRD4 PROTAC PEGylated nanoliposomes for the treatment of vemurafenib-resistant melanoma

Limited treatment options and development of resistance to targeted therapy within few months pose significant challenges in the treatment of BRAF-mutated malignant melanoma. Moreover, extensive angiogenesis and vasculogenic mimicry promote the rapid progression of disease. The purpose of this study was to develop a protein kinase C inhibitor anchored BRD4 PROTAC (ARV) loaded PEGylated nanoliposomes (LARPC). Palmitoyl-dl-carnitine chloride (PC) was used as a protein kinase C inhibitor to provide a cationic surface charge to LARPC. The formulation was characterized for particle size, zeta potential, drug release and various cell culture assays using HUVEC and vemurafenib resistant melanoma cells. The particle size of LARPC was found to be 105.25 ± 2.76 nm with a zeta potential of +26.6 ± 6.25 mV. Inhibition of angiogenesis was demonstrated by ARV and LARPC using human umbilical vein endothelial cells (HUVEC)-based matrigel basement membrane model. Additionally, LARPC demonstrated very low IC50 with promising inhibition of vasculogenic mimicry channel formation, cell migration as well as colony formation in vemurafenib-resistant melanoma cell lines. Hence, the outcome of this combination therapy indicated the suitability of LARPC as a potential and novel approach for eradicating vemurafenib-resistant melanoma.

Vegetable Oil-based Hybrid Submicron Particles Loaded with JMV5038: A Promising Formulation against Melanoma

The aim of this work was to carry out a preformulation study on JMV5038 as a new potent cytotoxic agent, and to develop its formulation within vegetable oil-based hybrid submicron particles (HNP) in order to obtain a versatile dosage form against melanoma. JMV5038 was first characterized through physico-chemical tests and it exhibited high melting point and logP value, an important pH-sensitivity that led to the formation of well-identified degradation products at low pH, as well as a substantial solubility value in silylated castor oil (ICO). Then, JMV5038-loaded HNP were formulated through a thermostabilized emulsion process based on the sol-gel cross-linking of ICO. They showed high loading efficiency and their in vitro release kinetic assessed in a biorelevant PBS/octanol biphasic system showed a constant sustained release over one month. The cytotoxic activity and cytocompatibility of HNP were evaluated on A375 melanoma cells and NIH 3T3 cells, respectively. JMV5038-loaded HNP exhibited a slightly enhanced cytotoxic activity of JMV5038 on melanoma cells while demonstrating their safety on NIH 3T3 cells. In conclusion, JMV5038-loaded HNP proved to be an efficient and safe drug subcutaneous delivery system that will be interesting to evaluate through preclinical studies.

TP53 mutation and tumoral PD-L1 expression are associated with depth of invasion in desmoplastic melanomas

BACKGROUND

Desmoplastic melanoma (DM) is a rare subtype of spindle cell malignant melanoma characterized by frequent local recurrences and hematogenous spread, but without molecular classification. The aim of the study was to investigate in a DM series the incidence of relevant gene alterations in cancer, the programmed death-ligand 1 (PD-L1) expression status and the association with clinicopathological features and melanoma progression.

METHODS

A total of 38 patients were included. Clinical follow-up and the histopathological features of all cases were retrospectively collected. PD-L1 expression by immunohistochemistry (IHC) and BRAF genomic alterations by real-time PCR were determined in 34 samples. Additionally, a molecular analysis by next-generation sequencing was performed in 25 DMs.

RESULTS

Tumors occurred predominantly in men (76%) and in the head and neck region (50%). Most tumors were pure DMs (66%), containing less than 10% of conventional melanoma. Overall, 48% of our cohort harbored TP53 mutations, most of them showing a molecular signature associated with ultraviolet (UV)-oncogenesis, and 29%, BRAF mutations. A positive correlation between TP53 with depth of invasion (P=0.005) and presence of elastosis (P=0.002) was found. High-expression of PD-L1 in tumor cells was observed in 38% of cases and correlated with depth of tumoral infiltration (P=0.003), TP53 (P=0.016), PD-1 (P<0.001) and tumor-infiltrating lymphocytes (TILS) (P<0.001). PD-L1 expression in immune cells correlated with PD-1 (P=0.006), tumoral PD-L1 expression (P=0.029) and TP53 mutation (P=0.002). Survival correlated with depth of invasion (P=0.003), stage of tumors (P=0.015), positive sentinel lymph node (P=0.004), lymph node metastasis (P=0.024) and distant metastasis (P<0.001).

CONCLUSIONS

Our results suggest that progressed DMs with deep tumoral infiltration frequently harbor TP53 mutations, PD-L1 expression and present a high inflammatory response, probably related to adaptive immune resistance in this tumor-type.

Targeting Mitochondria in Melanoma

Drastically elevated glycolytic activity is a prominent metabolic feature of cancer cells. Until recently it was thought that tumor cells shift their entire energy production from oxidative phosphorylation (OXPHOS) to glycolysis. However, new evidence indicates that many cancer cells still have functional OXPHOS, despite their increased reliance on glycolysis. Growing pre-clinical and clinical evidence suggests that targeting mitochondrial metabolism has anti-cancer effects. Here, we analyzed mitochondrial respiration and the amount and activity of OXPHOS complexes in four melanoma cell lines and normal human dermal fibroblasts (HDFs) by Seahorse real-time cell metabolic analysis, immunoblotting, and spectrophotometry. We also tested three clinically approved antibiotics, one anti-parasitic drug (pyrvinium pamoate), and a novel anti-cancer agent (ONC212) for effects on mitochondrial respiration and proliferation of melanoma cells and HDFs. We found that three of the four melanoma cell lines have elevated glycolysis as well as OXPHOS, but contain dysfunctional mitochondria. The antibiotics produced different effects on the melanoma cells and HDFs. The anti-parasitic drug strongly inhibited respiration and proliferation of both the melanoma cells and HDFs. ONC212 reduced respiration in melanoma cells and HDFs, and inhibited the proliferation of melanoma cells. Our findings highlight ONC212 as a promising drug for targeting mitochondrial respiration in cancer.

Discoidin Domain Receptors in Melanoma: Potential Therapeutic Targets to Overcome MAPK Inhibitor Resistance

Melanoma is a highly malignant skin cancer with high propensity to metastasize and develop drug resistance, making it a difficult cancer to treat. Current therapies targeting BRAF (V600) mutations are initially effective, but eventually tumors overcome drug sensitivity and reoccur. This process is accomplished in part by reactivating alternate signaling networks that reinstate melanoma proliferative and survival capacity, mostly through reprogramming of receptor tyrosine kinase (RTK) signaling. Evidence indicates that the discoidin domain receptors (DDRs), a set of RTKs that signal in response to collagen, are part of the kinome network that confer drug resistance. We previously reported that DDR1 is expressed in melanomas, where it can promote tumor malignancy in mouse models of melanoma, and thus, DDR1 could be a promising target to overcome drug resistance. In this review, we summarize the current knowledge on DDRs in melanoma and their implication for therapy, with emphasis in resistance to MAPK inhibitors.