BRAF as therapeutic target in melanoma

Structure-Based De Novo Design for the Discovery of Miniprotein Inhibitors Targeting Oncogenic Mutant BRAF

Being a component of the Ras/Raf/MEK/ERK signaling pathway crucial for cellular responses, the VRAF murine sarcoma viral oncogene homologue B1 (BRAF) kinase has emerged as a promising target for anticancer drug discovery due to oncogenic mutations that lead to pathway hyperactivation. Despite the discovery of several small-molecule BRAF kinase inhibitors targeting oncogenic mutants, their clinical utility has been limited by challenges such as off-target effects and suboptimal pharmacological properties. This study focuses on identifying miniprotein inhibitors for the oncogenic V600E mutant BRAF, leveraging their potential as versatile drug candidates. Using a structure-based de novo design approach based on binding affinity to V600E mutant BRAF and hydration energy, 39 candidate miniprotein inhibitors comprising three helices and 69 amino acids were generated from the substructure of the endogenous ligand protein (14-3-3). Through in vitro binding and kinase inhibition assays, two miniproteins (63 and 76) were discovered as novel inhibitors of V600E mutant BRAF with low-micromolar activity, with miniprotein 76 demonstrating a specific impediment to MEK1 phosphorylation in mammalian cells. These findings highlight miniprotein 76 as a potential lead compound for developing new cancer therapeutics, and the structural features contributing to its biochemical potency against V600E mutant BRAF are discussed in detail.

Neoadjuvant BRAF-targeted therapy for ameloblastoma of the mandible: an organ preservation approach

BACKGROUND

Ameloblastoma is a rare odontogenic neoplasm frequently located in the mandible. Standard treatment involves radical bone resection and immediate reconstruction, causing functional, aesthetic, and psychological impairments. The BRAF V600E mutation is present in approximately 80% of mandible ameloblastomas, and BRAF inhibitors have demonstrated sustained responses in unresectable cases.

METHODS

We identified ameloblastoma patients planned for ablative surgery and screened them for BRAF V600E mutation. Neoadjuvant BRAF inhibitors were offered to facilitate jaw preservation surgery. Retrospective data collection encompassed treatment regimens, tolerability, tumor response, and conversion to mandible preservation surgery.

RESULTS

Between 2017 and 2022, a total of 11 patients received dabrafenib (n = 6) or dabrafenib with trametinib (n = 5). The median age was 19 (range = 10-83) years. Median treatment duration was 10 (range = 3-20) months. All (100%) patients achieved a radiological response. Ten (91%) patients successfully converted to mandible preservation surgery with residual tumor enucleation. One patient attained complete radiological response, and surgery was not performed. Among the 10 surgically treated patients, all exhibited a pathological response, with 4 achieving near complete response and 6 partial response. At a median follow-up of 14 (range = 7-37) months after surgery, 1 case of recurrence was observed. Grade 1-2 adverse effects were reported in 8 (73%) patients, with a single case of grade 3 (hepatitis). Dose modification was necessary for 3 patients, and 4 experienced treatment interruptions, while 1 patient permanently discontinued therapy.

CONCLUSIONS

Neoadjuvant BRAF inhibition may offer a safe and effective strategy for organ preservation in mandible ameloblastoma treatment.

Exploring TTN variants as genetic insights into cardiomyopathy pathogenesis and potential emerging clues to molecular mechanisms in cardiomyopathies

The giant protein titin (TTN) is a sarcomeric protein that forms the myofibrillar backbone for the components of the contractile machinery which plays a crucial role in muscle disorders and cardiomyopathies. Diagnosing TTN pathogenic variants has important implications for patient management and genetic counseling. Genetic testing for TTN variants can help identify individuals at risk for developing cardiomyopathies, allowing for early intervention and personalized treatment strategies. Furthermore, identifying TTN variants can inform prognosis and guide therapeutic decisions. Deciphering the intricate genotype-phenotype correlations between TTN variants and their pathologic traits in cardiomyopathies is imperative for gene-based diagnosis, risk assessment, and personalized clinical management. With the increasing use of next-generation sequencing (NGS), a high number of variants in the TTN gene have been detected in patients with cardiomyopathies. However, not all TTN variants detected in cardiomyopathy cohorts can be assumed to be disease-causing. The interpretation of TTN variants remains challenging due to high background population variation. This narrative review aimed to comprehensively summarize current evidence on TTN variants identified in published cardiomyopathy studies and determine which specific variants are likely pathogenic contributors to cardiomyopathy development.

Epidermal growth factor receptor dual-target inhibitors as a novel therapy for cancer: A review

Overexpression of the epidermal growth factor receptor (EGFR) has been linked to several human cancers, including esophageal cancer, pancreatic cancer, anal cancer, breast cancer, and lung cancer, particularly non-small cell lung cancer (NSCLC). Therefore, EGFR has emerged as a critical target for treating solid tumors. Many 1st-, 2nd-, 3rd-, and 4th-generation EGFR single-target inhibitors with clinical efficacy have been designed and synthesized in recent years. Drug resistance caused by EGFR mutations has posed a significant challenge to the large-scale clinical application of EGFR single-target inhibitors and the discovery of novel EGFR inhibitors. Therapeutic methods for overcoming multipoint EGFR mutations are still needed in medicine. EGFR dual-target inhibitors are more promising than single-target inhibitors as they have a lower risk of drug resistance, higher efficacy, lower dosage, and fewer adverse events. EGFR dual-target inhibitors have been developed sequentially to date, providing new options for remission in patients with previously untreatable malignancies and laying the groundwork for a future generation of compounds. This paper introduces the EGFR family proteins and their synergistic effects with other anticancer targets, and provides a comprehensive review of the development of EGFR dual-target inhibitors in cancer, as well as the opportunities and challenges associated with those fields.

Challenges and Opportunities in the Crusade of BRAF Inhibitors: From 2002 to 2022

Serine/threonine-protein kinase B-Raf (BRAF; RAF = rapidly accelerated fibrosarcoma) plays an important role in the mitogen-activated protein kinase (MAPK) signaling cascade. Somatic mutations in the BRAF gene were first discovered in 2002 by Davies et al., which was a major breakthrough in cancer research. Subsequently, three different classes of BRAF mutants have been discovered. This class includes class I monomeric mutants (BRAFV600), class II BRAF homodimer mutants (non-V600), and class III BRAF heterodimers (non-V600). Cancers caused by these include melanoma, thyroid cancer, ovarian cancer, colorectal cancer, nonsmall cell lung cancer, and others. In this study, we have highlighted the major binding pockets in BRAF protein, their active and inactive conformations with inhibitors, and BRAF dimerization and its importance in paradoxical activation and BRAF mutation. We have discussed the first-, second-, and third-generation drugs approved by the Food and Drug Administration and drugs under clinical trials with all four different binding approaches with DFG-IN/OUT and αC-IN/OUT for BRAF protein. We have investigated particular aspects and difficulties with all three generations of inhibitors. Finally, this study has also covered recent developments in synthetic BRAF inhibitors (from their discovery in 2002 to 2022), their unique properties, and importance in inhibiting BRAF mutants.

An updated literature on BRAF inhibitors (2018-2023)

BRAF is the most common serine-threonine protein kinase and regulates signal transduction from RAS to MEK inside the cell. The BRAF is a highly active isoform of RAF kinase. BRAF has two domains such as regulatory and kinase domains. The BRAF inhibitors bind in the c-terminus of the kinase domain and inhibit the downstream pathways. The mutation occurs mainly in the A-loop of the kinase domain. The mutation occurs due to a conversion of valine to glutamate/lysine/arginine/aspartic acid at 600th position. Among the diverse mutations, BRAF^V600E is the most common and responsible for numerous cancer such as melanoma, colorectal, ovarian, and thyroid cancer. Due to mutations in RAC1, loss of PTEN, NF1, CCND1, USP28-FBW7 complex, COT overexpression, and CCND1 amplification, the BRAF kinase enzyme developed resistance over the commercially available BRAF inhibitors. There is still unmute urgence for the development of BRAF inhibitors to overcome the persistent limitation such as resistance, mutation, and adverse effects of drugs. In the current study, we described the structure, activation, downstream signaling pathway, and mutation of BRAF. Our group also provided a detailed review of BRAF inhibitors from the last five years (2018-2023) highlighting the structure-activity relationship, mechanistic study, and molecular docking studies. We hope that the current analysis will be a useful resource for researchers and provide chemists a glimpse into the future as design and development of more effective and secure BRAF kinase inhibitors. The development of BRAF inhibitors to overcome the persistent limitation such as resistance, mutation, and adverse effects of drugs. In depth description about different heterocyclic scaffolds (quinoline, imidazole, pyridine, triazole, pyrrole etc.) as BRAF inhibitors from the last five years (2018-2023) highlighting the structure-activity relationship, mechanistic study, and molecular docking studies.

Cutaneous Adverse Events of Systemic Melanoma Treatments: A Retrospective Single-Center Analysis

Recent progress in the treatment of advanced melanoma has led to the improved survival of affected patients. However, novel treatments also lead to considerable and distinct skin toxicity. To further characterize cutaneous adverse events (AE) of systemic treatments, we conducted a single-center retrospective study of biopsy-proven cutaneous adverse events of melanoma treatment over a period of 10 years at the University Hospital of Zurich, Switzerland. In 102 identified patients, 135 individual skin AEs developed. Immune checkpoint blockade (ICB) was causal for 81 skin AEs, and 54 were related to targeted therapies (TT). Recorded types of skin AEs included lichenoid, maculopapular, acneiform, urticarial, panniculitis, folliculitis, psoriasiform, granulomatous, eczematous, and others. The incidence of skin AEs was higher with TT (18.54%) than with ICB (9.64%, p = 0.0029). Most AEs were low-grade, although 19.21% of AEs were common terminology criteria for adverse events (CTCAE) Grades 3 or 4. A large spectrum of skin AEs was documented during treatment of advanced melanoma, and distinct phenotypes were observed, depending on treatment classes. AEs occurred earlier during treatment with TT than with ICB, and distinct types of skin AEs were associated with respective treatment classes. This study comprehensively describes skin AEs occurring during systemic treatment for melanoma at a single center.

Long-term outcomes in patients with relapsed or refractory hairy cell leukemia treated with vemurafenib monotherapy

Vemurafenib, an oral BRAF inhibitor, has demonstrated high response rates in relapsed/refractory (R/R) hairy cell leukemia (HCL). However, little is known about long-term outcomes and response to retreatment. Herein, we report the results of 36 patients with R/R HCL treated with vemurafenib from the United States arm of the phase 2 clinical trial (NCT01711632). The best overall response rate was 86%, including 33% complete response (CR) and 53% partial response (PR). After a median follow-up of 40 months, 21 of 31 responders (68%) experienced relapse with a median relapse-free survival (RFS) of 19 months (range, 12.5-53.9 months). There was no significant difference in the RFS for patients with CR vs PR. Fourteen of 21 (67%) relapsed patients were retreated with vemurafenib, with 86% achieving complete hematologic response. Two patients acquired resistance to vemurafenib with the emergence of new KRAS and CDKN2A mutations, respectively. Six of 12 (50%) responders to vemurafenib retreatment experienced another relapse with a median RFS of 12.7 months. Overall survival (OS) was 82% at 4 years, with a significantly shorter OS in patients who relapsed within 1 year of initial treatment with vemurafenib. Higher cumulative doses or a longer duration of treatment did not lengthen the durability of response. All adverse events in the retreatment cohort were grade 1/2 except for 1 case of a grade 3 rash and 1 grade 3 fever/pneumonia. Our data suggest that vemurafenib retreatment is a safe and effective option for patients with R/R HCL.

A novel melanoma prognostic model based on the ferroptosis-related long non-coding RNA

Ferroptosis is an iron-dependent programmed cell death related to the biological process of many kinds of tumors. Long noncoding RNAs (LncRNA) have been found to play essential roles in the tumor, and their functions in the ferroptosis of tumor cells have been partially discovered. However, there is no summary of ferroptosis-related LncRNA and its functions in melanoma. In the present study, we aim to explore the expression profile of ferroptosis-related LncRNA genes and their value in melanoma prognosis by bioinformatics analysis. The expression of ferroptosis-related gene (FRG) from melanoma clinical data was extracted based on the Cancer Genome Atlas (TCGA) database. By screening the RNA expression data of 472 cases of melanoma and 810 cases of normal skin, eighteen ferroptosis-related differential genes were found to be related to the overall survival rate. Furthermore, 384 ferroptosis-related LncRNAs were discovered through constructing the mRNA-LncRNA co-expression network, and ten of them were found with prognostic significance in melanoma by multivariate Cox analysis. Risk assessment showed that the high expression of LncRNA00520 is associated with poor prognosis, while the increased expression of the other LncRNA is beneficial to the prognosis of patients with melanoma. From univariate and multivariate Cox regression analysis, there were ten ferroptosis-related LncRNA risk models towards to be significant independent prognostic factors for patients with melanoma and valuable predictive factors for overall survival (OS)(P<0.05). The ROC curve further suggested that the risk score has relatively reliable predictive ability (AUC=0.718). The protein level of ferroptosis-related genes was verified by the HPA database and IHC test, leading to the discovery that the expressions of ALOX5, PEBP1, ACSL4, and ZEB1 proteins up-regulated in tumor tissues, and existed differences between tumor tissues and normal tissues. In conclusion, we identified ten ferroptosis-related LncRNA and constructed a prognosis model base.

Development of Dual Inhibitors Targeting Epidermal Growth Factor Receptor in Cancer Therapy

Epidermal growth factor receptor (EGFR) is of great significance in mediating cell signaling transduction and tumor behaviors. Currently, third-generation inhibitors of EGFR, especially osimertinib, are at the clinical frontier for the treatment of EGFR-mutant non-small-cell lung cancer (NSCLC). Regrettably, the rapidly developing drug resistance caused by EGFR mutations and the compensatory mechanism have largely limited their clinical efficacy. Given the synergistic effect between EGFR and other compensatory targets during tumorigenesis and tumor development, EGFR dual-target inhibitors are promising for their reduced risk of drug resistance, higher efficacy, lower dosage, and fewer adverse events than those of single-target inhibitors. Hence, we present the synergistic mechanism underlying the role of EGFR dual-target inhibitors against drug resistance, their structure-activity relationships, and their therapeutic potential. Most importantly, we emphasize the optimal target combinations and design strategies for EGFR dual-target inhibitors and provide some perspectives on new challenges and future directions in this field.

Choroidal vasculature analysis in MEK inhibitor-associated retinopathy

PURPOSE

To evaluate choroidal vascularity index (CVI) in patients developing mitogen-activated protein kinase kinase (MEK) inhibitor-associated retinopathy (MEKAR).

METHODS

In this prospective observational study, extensive ophthalmic examination was performed, including enhanced-depth-imaging-optical coherence tomography (EDI-OCT). EDI-OCT scans of patients receiving Cobimetinib, taken at baseline and at MEKAR manifestation, were considered for choroid analysis. Choroidal thickness (CT) was measured on high-resolution b-scans passing through the fovea at three different locations. Same scans were therefore imported for binarization into a previously reported software and CVI was calculated as the ratio of luminal area (LA) to total choroid area (TCA).

RESULTS

When compared to baseline, eyes with MEKAR (14 eyes) did not show significative CT variation in subfoveal region (p = 0,57), 750-µm-nasal to the fovea (p = 0,08) and 750-µm-temporal to the fovea (p = 0,07). Similarly, there were no statistically significant differences for TCA (p = 0.54), LA (p = 0.85), stromal area (SA) (p = 0.13), LA/SA (p = 0.34) and CVI (p = 0.47). Best-corrected visual acuity was significantly reduced at fluid accumulation when compared to baseline values (p = 0.03), with complete recovery after fluid resolution (p = 0.73).

CONCLUSION

Multiple parameters reflecting the status of the choroid seemed not influenced by Cobimetinib administration. Retinal pigment epithelium toxic disfunction likely represents the crucial step in MEKAR pathogenesis.

Recent advances in B-RAF inhibitors as anticancer agents

The significance of B-RAF in the promotion of cell proliferation and motility was explored by the researchers in the past. However, in 2002, several researchers found that mutation in B-RAF leads to cancer. Extensive research on B-RAF mutations suggested B-RAF V600E mutation as a critical predictive, prognostic and diagnostic biomarker in numerous cancers such as melanoma, thyroid, and colorectal cancers. Based on the significance of B-RAF kinase and associated mutation, the present review will give a brief overview about structure and functions of B-RAF enzyme, its role in different types of cancer, available drugs in the market for B-RAF inhibition, chemical classification and SAR studies of reported investigational B-RAF inhibitors in patented and non-patented literature during last decade. The SAR provided for all the reported inhibitors will help researchers to gain knowledge about the possible structural features required for selective B-RAF inhibition. This insightful analysis of B-RAF will certainly help researchers to develop novel anticancer agents in the future.

A radiologist’s guide to novel anticancer therapies in the era of precision medicine

Novel anticancer agents have replaced conventional chemotherapy as first line agents for many cancers, with continued new and expanding indications. Small molecule inhibitors act on cell surface or intracellular targets and prevent the downstream signaling that would otherwise permit tumor growth and spread. Anticancer antibodies can be directed against growth factors or may be immunotherapeutic agents. The latter act by inhibiting mechanisms that cancer cells use to evade the immune system. Hormonal agents act by decreasing levels of hormones that are necessary for the growth of certain cancer cells. Cancer therapy protocols often include novel anticancer agents and conventional chemotherapy used successively or in combination, in order to maximize survival and minimize morbidity. A working knowledge of anti-cancer drug classification will aid the radiologist in assessing response on imaging.

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Novel anticancer agents include small molecule inhibitors, antibodies and hormones.

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These agents are predominantly cytostatic and inhibit factors that provide a survival advantage to tumor cells.

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Modern cancer therapy employs a combination of novel anticancer agents and conventional chemotherapy.

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It is essential for radiologists to have a broad understanding of these agents and their mechanisms of action.

Genetic and Genomic Pathways of Melanoma Development, Invasion and Metastasis

Melanoma is a serious form of skin cancer that accounts for 80% of skin cancer deaths. Recent studies have suggested that melanoma invasiveness is attributed to phenotype switching, which is a reversible type of cell behaviour with similarities to epithelial to mesenchymal transition. Phenotype switching in melanoma is reported to be independent of genetic alterations, whereas changes in gene transcription, and epigenetic alterations have been associated with invasiveness in melanoma cell lines. Here, we review mutational, transcriptional, and epigenomic alterations that contribute to tumour heterogeneity in melanoma, and their potential to drive melanoma invasion and metastasis. We also discuss three models that are hypothesized to contribute towards aspects of tumour heterogeneity and tumour progression in melanoma, namely the clonal evolution model, the cancer stem cell model, and the phenotype switching model. We discuss the merits and disadvantages of each model in explaining tumour heterogeneity in melanoma, as a precursor to invasion and metastasis.

Transdermal Delivery of Chemotherapeutics: Strategies, Requirements, and Opportunities

Chemotherapeutic drugs are primarily administered to cancer patients via oral or parenteral routes. The use of transdermal drug delivery could potentially be a better alternative to decrease the dose frequency and severity of adverse or toxic effects associated with oral or parenteral administration of chemotherapeutic drugs. The transdermal delivery of drugs has shown to be advantageous for the treatment of highly localized tumors in certain types of breast and skin cancers. In addition, the transdermal route can be used to deliver low-dose chemotherapeutics in a sustained manner. The transdermal route can also be utilized for vaccine design in cancer management, for example, vaccines against cervical cancer. However, the design of transdermal formulations may be challenging in terms of the conjugation chemistry of the molecules and the sustained and reproducible delivery of therapeutically efficacious doses. In this review, we discuss the nano-carrier systems, such as nanoparticles, liposomes, etc., used in recent literature to deliver chemotherapeutic agents. The advantages of transdermal route over oral and parenteral routes for popular chemotherapeutic drugs are summarized. Furthermore, we also discuss a possible in silico approach, Formulating for Efficacy™, to design transdermal formulations that would probably be economical, robust, and more efficacious.

Current Status and Prospects of Immunotherapy for Gynecologic Melanoma

Gynecologic melanomas are rare and have a poor prognosis. Although immunotherapy (immune checkpoint inhibitors) and targeted therapy has greatly improved the systemic treatment of cutaneous melanoma (CM) in recent years, its efficacy in gynecologic melanomas remains uncertain because of the rarity of this malignancy and its scarce literature. This review aimed to evaluate the literature of gynecologic melanomas treated with immunotherapy and targeted therapy through a PubMed search. We identified one study focusing on the overall survival of gynecologic melanomas separately and five case series and nine case reports concentrating on gynecologic melanomas treated with an immune checkpoint inhibitor and/or targeted therapy. Furthermore, the KIT mutation has the highest rate among all mutations in mucosal melanoma types. The KIT inhibitors (Tyrosine kinase inhibitors: TKIs) imatinib and nilotinib could be the treatment options. Moreover, immune checkpoint inhibitors combined with KIT inhibitors may potentially treat cases of resistance to immune checkpoint inhibitors. However, because of the different conditions and a small number of cases, it is difficult to evaluate the efficacy of immunotherapy and targeted therapy for gynecologic melanoma rigorously at this time. Further prospective cohort or randomized trials of gynecologic melanoma alone are needed to assess the treatment with solid evidence.

Olig2 regulates p53-mediated apoptosis, migration and invasion of melanoma cells

Melanoma is a disease with a high recurrence rate and poor prognosis; therefore, the need for targeted therapeutics is steadily increasing. Oligodendrocyte transcription factor2 (Olig2) is a basic helix-loop-helix transcription factor that is expressed in the central nervous system during embryonic development. Olig2 is overexpressed in various malignant cell lines such as lung carcinoma, glioma and melanoma. Olig2 is known as a key transcription factor that promotes tumor growth in malignant glioma. However, the role of Olig2 in melanoma is not well characterized. We analyzed the role of Olig2 in apoptosis, migration, and invasion of melanoma cells. We confirmed that Olig2 was overexpressed in melanoma cells and tissues. Reduction of Olig2 increased apoptosis in melanoma cells by increasing p53 level and caspase-3/-7 enzyme activity. In addition, downregulation of Olig2 suppressed migration and invasion of melanoma cells by inhibiting EMT. Reduction of Olig2 inhibited expression of MMP-1 and the enzyme activity of MMP-2/-9 induced by TGF-β. Moreover, Olig2 was involved in the downstream stages of MEK/ERK and PI3K/AKT, which are major signaling pathways in metastatic progression of melanoma. In conclusion, this study demonstrated the crucial roles of Olig2 in apoptosis, migration, and invasion of melanoma and may help to further our understanding of the relationship between Olig2 and melanoma progression.

Resistance to Molecularly Targeted Therapies in Melanoma

Malignant melanoma is the most aggressive type of skin cancer with invasive growth patterns. In 2021, 106,110 patients are projected to be diagnosed with melanoma, out of which 7180 are expected to die. Traditional methods like surgery, radiation therapy, and chemotherapy are not effective in the treatment of metastatic and advanced melanoma. Recent approaches to treat melanoma have focused on biomarkers that play significant roles in cell growth, proliferation, migration, and survival. Several FDA-approved molecular targeted therapies such as tyrosine kinase inhibitors (TKIs) have been developed against genetic biomarkers whose overexpression is implicated in tumorigenesis. The use of targeted therapies as an alternative or supplement to immunotherapy has revolutionized the management of metastatic melanoma. Although this treatment strategy is more efficacious and less toxic in comparison to traditional therapies, targeted therapies are less effective after prolonged treatment due to acquired resistance caused by mutations and activation of alternative mechanisms in melanoma tumors. Recent studies focus on understanding the mechanisms of acquired resistance to these current therapies. Further research is needed for the development of better approaches to improve prognosis in melanoma patients. In this article, various melanoma biomarkers including BRAF, MEK, RAS, c-KIT, VEGFR, c-MET and PI3K are described, and their potential mechanisms for drug resistance are discussed.

Distribution pattern of tumor infiltrating lymphocytes and tumor microenvironment composition as prognostic indicators in anorectal malignant melanoma

Anorectal malignant melanoma (ARMM) is a rare disease with poor prognosis. Determining ARMM prognosis precisely is difficult due to the lack of proper assessment techniques. Immunotherapy has proven effective against cutaneous malignant melanoma and may show efficacy in ARMM. Herein, we assessed the immune profile of ARMM to identify possible prognostic biomarkers. Twenty-two ARMM formalin-fixed and paraffin-embedded samples were evaluated using an nCounter^® PanCancer Immune Profiling Panel. Validation was performed through immunohistochemical staining for CD3, CD8, Foxp3, CD68, CD163, and PD-L1. RNA analysis revealed significantly decreased scores for pathways involved in cell regulation and function, as well as chemokines, in recurrent patients compared to nonrecurrent patients. In cell-type profiling, the recurrent cases displayed significantly low tumor infiltrating lymphocyte (TIL) scores. Recurrence/death prediction models were defined using logistic regression and showed significantly lower scores in recurrent and deceased patients (all, P < 0.001) compared to those in nonrecurrent and surviving patients. The high total TIL and tumor-associated macrophage (TAM) groups had significantly better overall survival outcomes compared to the low total TIL and TAM groups (P = 0.007 and P = 0.035, respectively). In addition, the presence of CD3 + TILs in the invasion front was an independent favorable prognostic indicator (P = 0.003, hazard ratio = 0.21, 95% confidential interval, 0.01-0.41). Patients with inflamed or brisk-infiltration type tumors also had a significantly better overall survival than that of patients with immune-desert/excluded and absent/non-brisk type tumors (P = 0.03 and P = 0.0023, respectively). In conclusion, TILs have a strong prognostic value in ARMM, and the quantification of TILs and an analysis of the TIL phenotype and infiltration pattern during pathological diagnosis are essential to guide treatment strategies and accurate prognosis in ARMM.

Fibroblast Growth Factor Receptor 3 Amplified Metastatic Melanoma Treated With Erdafitinib

The treatment of metastatic melanoma has changed dramatically in the last decade with the introduction of immunotherapy and targeted therapy. A futile disease in the past is now treated with various options, resulting in improvement in progression-free and overall survivals, along with improvement in the quality of life. Having said that, the majority of patients with metastatic melanoma eventually succumb to the disease. Molecular profiling of each tumor in the advanced stage is standard of care now, as this would lead to individualized treatment options for each patient. Here, we present a rare case of fibroblast growth factor receptor 3 (FGFR 3) amplified metastatic melanoma, treated rather unconventionally with FGFR 3 inhibitor erdafitinib.

Development, Characterization and Use of Liposomes as Amphipathic Transporters of Bioactive Compounds for Melanoma Treatment and Reduction of Skin Inflammation: A Review

The skin is the largest organ in the human body, providing a barrier to the external environment. It is composed of three layers: epidermis, dermis and hypodermis. The most external epidermis is exposed to stress factors that may lead to skin conditions such as photo-aging and skin cancer. Some treatments for skin disease utilize the incorporation of drugs or bioactive compounds into nanocarriers known as liposomes. Liposomes are membranes whose sizes range from nano to micrometers and are composed mostly of phospholipids and cholesterol, forming similar structures to cell membranes. Thus, skin treatments with liposomes have lower toxicity in comparison to traditional treatment routes such as parenteral and oral. Furthermore, addition of edge activators to the liposomes decreases the rigidity of the bilayer structure making it deformable, thereby improving skin permeability. Liposomes are composed of an aqueous core and a lipidic bilayer, which confers their amphiphilic property. Thus, they can carry hydrophobic and hydrophilic compounds, even simultaneously. Current applications of these nanocarriers are mainly in the cosmetic and pharmaceutic industries. Nevertheless, new research has revealed promising results regarding the effectiveness of liposomes for transporting bioactive compounds through the skin. Liposomes have been well studied; however, additional research is needed on the efficacy of liposomes loaded with bioactive peptides for skin delivery. The objective of this review is to provide an up-to-date description of existing techniques for the development of liposomes and their use as transporters of bioactive compounds in skin conditions such as melanoma and skin inflammation. Furthermore, to gain an understanding of the behavior of liposomes during the process of skin delivery of bioactive compounds into skin cells.

BRAF mutational status as a prognostic marker for survival in malignant melanoma: a systematic review and meta-analysis

Background: The analysis of the BRAF mutational status has been established as a standard procedure during diagnosis of advanced malignant melanoma due to the fact that BRAF inhibitors constitute a cornerstone in the treatment of metastatic disease. However, the general impact of BRAF mutational status on survival remains unclear. Our study aimed to assess the underlying prognostic significance of BRAF mutant versus wild type (WT) malignant melanoma on overall survival (OS), disease-free survival (DFS) and progression-free survival (PFS).Material and methods: A systematic literature search in EMBASE, Medline and Cochrane CENTRAL was performed. Studies were included if they reported survival outcomes for BRAF mutant versus WT patients as hazard ratios (HR) or in Kaplan-Meier (KM) curves. Random-effects meta-analysis models were used to pool HRs across the studies.Results: Data from 52 studies, representing 7519 patients, were pooled for analysis of OS. The presence of a BRAF mutation was statistically significantly associated with a reduced OS (HR [95% confidence interval (CI)]: 1.23 [1.09-1.38]), however, with substantial heterogeneity between the studies (I²: 58.0%). Meta-regression and sensitivity analyses showed that age, sex and BRAF mutation testing method did not have a significant effect on the OS HR. BRAF mutant melanoma showed comparable effect on DFS to non-BRAF mutant melanoma in stage I-III melanoma (combined HR: 1.16, 95% CI: 0.92-1.46), and on PFS in stage III-IV (HR: 0.98 (95% CI: 0.68-1.40)).Conclusion: Although there was substantial heterogeneity between the studies, the overall results demonstrated a poorer prognosis and OS in patients harbouring BRAF mutations. Future studies should take this into account when evaluating epidemiological data and treatment effects of new interventions in patients with malignant melanoma.

Cell-free DNA BRAF V600E measurements during BRAF inhibitor therapy of metastatic melanoma: long-term analysis

OBJECTIVE

We assessed the status of the BRAF V600E mutation in cell-free circulating tumor DNA (cfDNA) isolated from the plasma of patients with metastatic melanoma treated with the BRAF inhibitor vemurafenib, collected at different time points during therapy to evaluate the sensitivity and specificity of quantitative polymerase chain reaction and droplet digital polymerase chain reaction (ddPCR) and the correlation between the level of plasma cfDNA p.V600E and the long-term clinical outcome.

METHODS

cfDNA in patients with BRAF-mutated melanoma (n = 62) was analyzed at baseline and at 4-8 weeks from the start of vemurafenib therapy. BRAF mutations were assessed using tumor tissue-derived DNA and circulating cfDNA from plasma samples. Quantification of BRAF V600E was performed in cfDNA using ddPCR.

RESULTS

cfDNA V600E was detected in the plasma of 48/62 (77%) patients at baseline and in 18/62 (29%) patients after 4-8 weeks of treatment. Patients positive for BRAF mutations in cfDNA at baseline had shorter progression-free survival (PFS) and overall survival (OS) compared with patients with undetectable cfDNA BRAF mutations. Undetectable cfDNA p.V600E at baseline and after 4-8 weeks of therapy was associated with the best prognosis. When treated as a continuous variable, the log-transformed concentration of baseline cfDNA p.V600E was significantly associated with both PFS and OS. This effect was retained in the multivariate OS Cox model adjusted for Eastern Cooperative Oncology Group performance status, the presence of brain metastases, patient age, and previous systemic treatment.

CONCLUSIONS

Monitoring of plasma BRAF p.V600E cfDNA concentrations in patients with metastatic melanoma on targeted therapy may have prognostic value. Undetectable cfDNA p.V600E before and during treatment was associated with a favorable prognosis.

KSRP modulates melanoma growth and efficacy of vemurafenib

The majority of melanomas carry an oncogenic BRAF mutation (BRAF^V600E), which results in constitutive kinase activity driving melanoma proliferation. While inhibitors of BRAF^V600E (BRAFi) effectively lead to rapid tumor shrinkage, most patients treated with BRAFi develop acquired resistance. Identification of factors as regulators of melanoma growth and as potential sources of resistance is thus crucial for the design of improved therapies to treat advanced melanoma with more durable responses. Here, we show that KH-type splicing regulatory protein (KSRP) is critical for proliferation of melanoma cells without and with acquired resistance to vemurafenib. Silencing KSRP reduces cell proliferation and augments the growth suppressive effects of vemurafenib. We identify killin (KLLN), a p53-regulated DNA replication inhibitor, as a downstream effector of growth inhibition by KSRP silencing and demonstrate that KSRP promotes decay of KLLN mRNA through an RNA-protein interaction. Using heterologous mRNA reporters, we show that a U-rich element within the 3' untranslated region of KLLN is responsible for KSRP-dependent mRNA decay. These findings implicate that KSRP is an important regulator of melanoma cell growth in part through controlling KLLN mRNA stability.

Cobimetinib- and vemurafenib-induced granulomatous dermatitis and erythema induratum: A case report

Metastatic melanoma is an aggressive malignancy. Survival can be increased with the combination of BRAF and MEK inhibition. BRAF inhibitor-induced cutaneous toxicities can be attenuated with MEK inhibition. Here, we describe the first reported case of a patient with metastatic melanoma who developed granulomatous dermatitis and erythema induratum when treated with combination BRAF (vemurafenib) and MEK inhibitor (cobimetinib) therapy and discuss the clinical features and management of dermatologic side-effects secondary to BRAF +/– MEK inhibition.

Adjuvant and Neoadjuvant Treatment of Skin Cancer

Skin cancer represents a broad classification of malignancies, which can be further refined by histology, including basal cell carcinoma, squamous cell carcinoma and melanoma. As these three cancers are distinct entities, we review each one separately, with a focus on their epidemiology, etiology including relevant genomic data, and the current evidence-based recommendations for adjuvant and neoadjuvant therapy. We also discuss future directions and opportunities for continued therapeutic advances.

Rapid BRAF mutation tests in patients with advanced melanoma: comparison of immunohistochemistry, Droplet Digital PCR, and the Idylla Mutation Platform

Supplemental Digital Content is available in the text.

BRAF mutational testing has become a common practice in the diagnostic process of patients with advanced melanoma. Although time-consuming, DNA sequencing techniques are the current gold standard for mutational testing. However, in certain clinical situations, a rapid test result is required. In this study, the performance of three rapid BRAF mutation tests was compared. Thirty-nine formalin-fixed paraffin-embedded melanoma tissue samples collected between 2007 and 2014 at a single center were included. These samples were analyzed by immunohistochemistry using the anti-BRAF-V600E (VE1) mouse monocolonal antibody (BRAF-VE1 IHC), a V600E-specific Droplet Digital PCR Test, and the Idylla BRAF- Mutation Test (Idylla). Results were compared with the results of conventional BRAF mutation testing, performed using high-resolution melting analysis followed by Sanger sequencing. Next-generation sequencing was performed on samples with discordant results. The Idylla test and Droplet Digital PCR Test correctly identified all mutated and wild-type samples. BRAF-VE1 IHC showed one discordant result. The Idylla test could identify BRAF-V600 mutations other than BRAF-V600E and was the fastest and least laborious test. The Idylla Mutation Test is the most suitable test for rapid BRAF testing in clinical situations on the basis of the broad coverage of treatment-responsive mutations and the fast procedure without the need to perform a DNA isolation step.

Cumingianoside A, a Phyto-Triterpenoid Saponin Inhibits Acquired BRAF Inhibitor Resistant Melanoma Growth via Programmed Cell Death

Mutated proto-oncogene BRAF is a bona fide therapeutic target for melanomas. Regrettably, melanoma acquires resistance to BRAF inhibitors, e.g., vemurafenib (PLX4032) casting doubt on this promising melanoma targeted therapy. In this study, we explored the bioactivity of triterpenoid saponin cumingianoside A (CUMA), isolated from leaves and twigs of Dysoxylum cumingianum against PLX4032-resistant BRAF^{V 600E} mutant melanoma A375-R in vitro and in vivo. Our data show that CUMA treatment inhibited A375-R melanoma cell proliferation in a time- and dose-dependent manner. CUMA also suppressed the activity of CDK1/cyclin B1 complex and led to G₂/M-phase arrest of A375-R cells. Furthermore, CUMA treatment resulted in induction of apoptosis as shown by the increased activation of caspase 3 and caspase 7, and the proteolytic cleavage of poly(ADP-ribose) polymerase (PARP). We also observed that CUMA induced autophagy-like activity in A375-R cells, as shown by the increased expression of autophagy-related genes and increased formation of autophagosomes. Moreover, we found that CUMA treatment induced ER stress response and co-treatment with an ER stress inhibitor (4-PBA) could attenuate apoptosis induced by CUMA. Importantly, orally administered CUMA as a single agent or in combination with PLX4032 exhibited strong tumor growth inhibition in a PLX4032-resistant A375-R xenograft mouse model, and with little toxicity. This is the first report to explore the anti-tumor activity of CUMA in vitro and in vivo mechanistically, and our results imply that this triterpenoid saponin may be suitable for development into an anti-melanoma agent.

Combatting mucosal melanoma: recent advances and future perspectives

Mucosal melanomas are a rare subtype of melanoma and are associated with a particularly poor prognosis. Due to the rarity of the diagnosis, and the pace with which the management of cutaneous melanoma has evolved over recent years, there is little good evidence to guide management and evidence-based clinical guidelines are still in development in the UK. In this review we provide an overview of the management of mucosal melanoma, highlighting the critical differences between cutaneous and mucosal melanomas, before examining recent advances in the systemic treatment of this disease and likely future directions.

Autophagic cell death associated to Sorafenib in renal cell carcinoma is mediated through Akt inhibition in an ERK1/2 independent fashion

OBJECTIVES

To fully clarify the role of Mitogen Activated Protein Kinase in the therapeutic response to Sorafenib in Renal Cell Carcinoma as well as the cell death mechanism associated to this kinase inhibitor, we have evaluated the implication of several Mitogen Activated Protein Kinases in Renal Cell Carcinoma-derived cell lines.

MATERIALS AND METHODS

An experimental model of Renal Cell Carcinoma-derived cell lines (ACHN and 786-O cells) was evaluated in terms of viability by MTT assay, induction of apoptosis by caspase 3/7 activity, autophagy induction by LC3 lipidation, and p62 degradation and kinase activity using phospho-targeted antibodies. Knock down of ATG5 and ERK5 was performed using lentiviral vector coding specific shRNA.

RESULTS

Our data discard Extracellular Regulated Kinase 1/2 and 5 as well as p38 Mitogen Activated Protein Kinase pathways as mediators of Sorafenib toxic effect but instead indicate that the inhibitory effect is exerted through the PI3K/Akt signalling pathway. Furthermore, we demonstrate that inhibition of Akt mediates cell death associated to Sorafenib without caspase activation, and this is consistent with the induction of autophagy, as indicated by the use of pharmacological and genetic approaches.

CONCLUSION

The present report demonstrates that Sorafenib exerts its toxic effect through the induction of autophagy in an Akt-dependent fashion without the implication of Mitogen Activated Protein Kinase. Therefore, our data discard the use of inhibitors of the RAF-MEK-ERK1/2 signalling pathway in RCC and support the use of pro-autophagic compounds, opening new therapeutic opportunities for Renal Cell Carcinoma.

Anticancer effects of combinational treatment with BRAFV600E siRNA and PI3K pathway inhibitors in melanoma cell lines harboring BRAFV600E

In the present study, the anti-tumor effects of combination treatment with an siRNA targeting B-Raf proto-oncogene serine/threonine kinase (BRAF)^V600E and phosphoinositide 3-kinase (PI3K) signaling pathway inhibitors was investigated in melanoma cell lines harboring BRAF^V600E. Human melanoma A375 and WM115 cells were treated with siRNA targeting to BRAF or BRAF^V600E, combined with treatment with PI3K signaling pathway inhibitors. CCK-8 and EdU proliferation assays were performed to assess cell viability and proliferation, respectively, following treatment. In addition, flow cytometry analysis was performed to determine cell cycle distribution, and western blot analysis was performed to analyze the activity of the extracellular signal-regulated kinase (ERK) and PI3Ksignaling pathways following treatment. Targeting BRAF^V600E using small interfering (si)RNA significantly decreased cell viability and DNA replication in tumor cell lines that harbor oncogenic BRAF^V600E. Inhibition of BRAF^V600E by siRNA combined with treatment with PI3K or mammalian target of rapamycin signaling pathway inhibitors significantly decreased cell viability and proliferation compared with siRNA or inhibitor treatment alone. Concomitant BRAF^V600E and PI3K inhibition led to G₁/S phase arrest in melanoma cells. However, melanoma cells in which oncogenic BRAF^V600E is not highly expressed (WM115 cells) were not sensitive to BRAF^V600E targeted therapy. The PI3K signaling pathway inhibitors were more effective in this cell line. The results from the present study provide an insight into the potential effectiveness of combination therapy and personalized cancer treatments.

A Case of Primary Gastric Melanoma Exhibiting a Rare BRAF V600R Mutation

Introduction

Malignant melanoma of the gastrointestinal tract is usually a metastasis from a cutaneous source. Primary gastric melanoma is an extremely rare clinical entity, with few reported cases worldwide. It is often advanced at time of diagnosis and is associated with a dismal outcome.

Background

A 76 year old gentleman presenteded with a one month history of fatigue and exertional dyspnoea. Laboratory investigations indicated an anaemia, with a haemoglobin level of 11.0g/dl. Subsequent gastroscopy visualised a large, atypical, crater-like ulcerated lesion distal to the cardia in the proximal stomach.

Provisional histology was suggestive of a poorly differentiated adenocarcinoma but subsequent cyto-morphology and immunophenotyping were consistent with melanoma, with positive S100 protein, HMB45 and Melan A. Further molecular genetic testing revealed a V600R mutation in the BRAF gene, which is the first primary gastric melanoma with this mutation to be reported in the literature. Given the rarity of the findings, an extensive secondary work-up was undertaken, which concluded the diagnosis primary gastric melanoma.

Discussion

Primary gastric melanoma is a rare disease that can present similarly to other upper gastrointesinal lesions, with weight loss, abdominal pain, malena, and anaemia. Given its rarity, the pathogenesis is poorly understood. Lesions are often endoscopically atypical. Important points to note would include the absence of a primary lesion, as supported by a full skin examination and PET-CT findings, which can help to delineate the limitation to the stomach, thus helping to inform subsequent management.

LEARNING POINTS

Treatment with combined dabrafenib and trametinib in BRAFV600E-mutated metastatic malignant melanoma: a case of long-term complete response after treatment cessation

Here, we report the case of a patient, diagnosed with BRAF^V600E-mutated metastatic malignant melanoma M1a, who achieved a complete metabolic response after 7 months of treatment with the combination of dabrafenib and trametinib. After 31 months, the treatment was interrupted for patient’s decision. To date October 2017, 18 months after the interruption of the treatment with the combination of dabrafenib and trametinib, follow-up Positron Emission Tomography (PET) scans are still documenting complete metabolic response.

Use of phosphodiesterase type 5 inhibitors and risk of melanoma: a meta-analysis of observational studies

Background

Phosphodiesterase type 5 inhibitor (PE5i) administration may stimulate the proliferation and survival of melanocytes. However, discrepancies remain regarding the association between PDE5i use and melanoma risk in observational studies in humans.

Aim

To evaluate the association between PDE5i use and melanoma in a meta-analysis.

Materials and methods

Studies were identified by searching the PubMed and Embase databases. A random-effects model was applied to synthesize the data. A stratified study was performed to evaluate the influence of study characteristics on outcomes.

Results

Four prospective cohort studies and three case–control studies with 1,534,615 male participants and 16,053 melanoma cases were incorporated. Patients who received a PDE5i had a significantly increased risk for melanoma (adjusted risk ratio [RR] =1.12, 95% CI =1.03–1.33, P=0.008) with moderate heterogeneity (I²=54%). Cohort studies (adjusted RR =1.22, 95% CI =1.02–1.46, P=0.03) largely contributed to this result rather than case–control studies. Subsequent stratified analyses revealed that sildenafil was associated with an increased risk of melanoma (adjusted RR =1.26, 95% CI =1.07–1.50, P=0.007), but tadalafil and vardenafil were not. Also, PDE5i use was associated with a significantly increased risk of in situ melanoma (adjusted RR =1.31, 95% CI =1.01–1.69, P=0.04), but not of localized or nonlocalized melanoma.

Conclusion

PDE5i use may be associated with a significantly increased risk for melanoma in men. However, further research is needed to determine whether the association is causative.

Uncommon BRAF Mutations Associated with Durable Response to Immunotherapy in Patients with Metastatic Melanoma

Melanoma is a disease process which has been increasing in incidence over the past three decades and metastatic melanoma carries a poor prognosis. Through genetic studies of this disease, it has been determined that the BRAF V600 mutation plays a major role in the pathophysiology of the disease and this has led to the utilization of targeted therapy (BRAF and MEK inhibitors) in its treatment. Other BRAF mutations (non-V600 mutations) are rare in melanoma and targeted therapy is not indicated for patients with these mutations due to reduced response rates. An emerging option for metastatic melanoma with uncommon BRAF mutations is immunotherapy using checkpoint inhibitors such as PD-1 inhibitors or CTLA-4 inhibitors. Currently, it is unknown how patients with BRAF non-V600 mutations respond to immunotherapy. This report will examine the effect of immunotherapy on two distinct metastatic melanoma patients, each with uncommon BRAF mutations, occurring outside the V600 locus (E586K and G469E). These patients were noted to have a durable, complete response when treated with immunotherapy and continue to exhibit a response 9 and 15 months after discontinuing therapy. Further research and clinical trials are needed to study patients with uncommon BRAF mutations and the potential therapeutic benefit of immunotherapy.

Novel diphenylthiazole derivatives with multi-target mechanism: Synthesis, docking study, anticancer and anti-inflammatory activities

Over the last few decades, a growing body of studies addressed the anticancer activity of NSAIDs, particularly selective COX-2 inhibitors. However, their exact molecular mechanism is still unclear and is not fully investigated. In this regard, a novel series of compounds bearing a COXs privilege scaffold, diphenyl thiazole, was synthesized and evaluated for their anticancer activity against a panel of cancer cell lines. The most active compounds 10b, 14a,b, 16a, 17a,b and 18b were evaluated in vitro for COX-1/COX-2 inhibitory activity. These compounds were suggested to exert their anticancer activity through a multi-target mechanism based on their structural features. Thus, compounds 10b and 17b with the least IC₅₀ values in MTT assay were tested against three known anticancer targets; EGFR, BRAF and tubulin. Compounds 10b and 17b showed remarkable activity against EGFR with IC₅₀ values of 0.4 and 0.2μM, respectively and good activity against BRAF with IC₅₀ values of 1.3 and 1.7μM, respectively. In contrast, they showed weak activity in tubulin polymerization assay. The in vivo anti-inflammatory potential was assessed and interestingly, compound 17b was the most potent compound. Together, this study offers some important insights into the correlation between COXs inhibition and cancer treatment. Additionally, the results demonstrated the promising activity of these compounds with a multi-target mechanism as good candidates for further development into potential anticancer agents.

MicroRNAs in Oncogenesis and Tumor Suppression

MicroRNAs (MiRNAs) have emerged in the last 15 years as central players in the biology of cancer. Increasing lines of evidence have supported their regulatory role in the expression of both oncogenes and tumor-suppressor genes, progressively clarifying which genes are modulated by specific MiRNAs dysregulated in cancer. Intriguingly, a "target-specific" understanding of MiRNA function in oncology has been replaced by a more "pathway-specific" vision of their involvement in cancer biology. This work provides a state-of-the-art knowledge of the role of MiRNAs in the most frequently altered signaling pathways in cancer cells and provides an updated overview on some of the most relevant findings trying to decode the complex molecular mechanisms of cancer.

Targeted Therapy in Systemic Sclerosis

Targeted therapies use an understanding of the pathophysiology of a disease in an individual patient. Although targeted therapy for systemic sclerosis (SSc, scleroderma) has not yet reached the level of patient-specific treatments, recent developments in the understanding of the global pathophysiology of the disease have led to new treatments based on the cells and pathways that have been shown to be involved in the disease pathogenesis. The presence of a B cell signature in skin biopsies has led to the trial of rituximab, an anti-CD20 antibody, in SSc. The well-known properties of transforming growth factor (TGF)-β in promoting collagen synthesis and secretion has led to a small trial of fresolimumab, a human IgG4 monoclonal antibody capable of neutralizing TGF-β. Evidence supporting important roles for interleukin-6 in the pathogenesis of SSc have led to a large trial of tocilizumab in SSc. Soluble guanylate cyclase (sGC) is an enzyme that catalyzes the production of cyclic guanosine monophosphate (cGMP) upon binding of nitric oxide (NO) to the sGC molecule. Processes such as cell growth and proliferation are regulated by cGMP. Evidence that sGC may play a role in SSc has led to a trial of riociguat, a molecule that sensitizes sGC to endogenous NO. Tyrosine kinases (TKs) are involved in a wide variety of physiologic and pathological processes including vascular remodeling and fibrogenesis such as occurs in SSc. This has led to a trial of nintedanib, a next-generation tyrosine-kinase (TK) inhibitor which targets multiple TKs, in SSc.

Regulatory properties of statins and rho gtpases prenylation inhibitiors to stimulate melanoma immunogenicity and promote anti-melanoma immune response

Melanoma is a highly lethal cutaneous tumor, killing affected patients through development of multiple poorly immunogenic metastases. Suboptimal activation of immune system by melanoma cells is often due to molecular modifications occurring during tumor progression that prevent efficient recognition of melanoma cells by immune effectors. Statins are HMG-CoA reductase inhibitors, which block the mevalonate synthesis pathway, used by millions of people as hypocholesterolemic agents in cardiovascular and cerebrovascular diseases. They are also known to inhibit Rho GTPase activation and Rho dependent signaling pathways. Rho GTPases are regarded as molecular switches that regulate a wide spectrum of cellular functions and their dysfunction has been characterized in various oncogenic process notably in melanoma progression. Moreover, these molecules can modulate the immune response. Since 10 years we have demonstrated that Statins and other Rho GTPases inhibitors are critical regulators of molecules involved in adaptive and innate anti-melanoma immune response. In this review we summarize our major observations demonstrating that these pharmacological agents stimulate melanoma immunogenicity and suggest a potential use of these molecules to promote anti-melanoma immune response.

Therapeutic approach to treating patients with BRAF-mutant lung cancer: latest evidence and clinical implications

Lung adenocarcinoma is known for its high rate of somatic mutations and genomic rearrangements. The identification of epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) rearrangements that sensitize tumors to specific drugs has changed the therapeutic approach and prognosis in these molecularly-defined subgroups. Several other key genetic alterations have been identified, of which BRAF mutations are found in 4% of non-small cell lung cancer (NSCLC) cases. Targeted drugs against BRAF and downstream MEK were recently approved for the treatment of BRAF-positive melanoma and have entered clinical evaluation in NSCLC. In this review we discuss the latest evidence on the treatment of BRAF-mutated NSCLC, including tumor biology, targeted treatment with BRAF and MEK inhibitors, therapeutic resistance and strategies to overcome resistance.

Copper suppression as cancer therapy: the rationale for copper chelating agents in BRAFV600 mutated melanoma

The successful targeting of oncogenic BRAF^V600 represents one of the landmark breakthroughs in therapy for advanced melanoma. While the initial clinical benefit can be dramatic, resistance is common due to a number of mechanisms, including MAPK pathway reactivation. Recent data have revealed a novel role for copper (Cu) in BRAF signaling with potential clinical implications. The history, preclinical data and efficacy of Cu chelating agents in cancer, specifically tetrathiomolybdate, will be reviewed with a focus on the rationale for targeting the MAPK cascade in melanoma through novel combination strategies.

Capture and On-chip analysis of Melanoma Cells Using Tunable Surface Shear forces

With new systemic therapies becoming available for metastatic melanoma such as BRAF and PD-1 inhibitors, there is an increasing demand for methods to assist with treatment selection and response monitoring. Quantification and characterisation of circulating melanoma cells (CMCs) has been regarded as an excellent non-invasive candidate but a sensitive and efficient tool to do these is lacking. Herein we demonstrate a microfluidic approach for melanoma cell capture and subsequent on-chip evaluation of BRAF mutation status. Our approach utilizes a recently discovered alternating current electrohydrodynamic (AC-EHD)-induced surface shear forces, referred to as nanoshearing. A key feature of nanoshearing is the ability to agitate fluid to encourage contact with surface-bound antibody for the cell capture whilst removing nonspecific cells from the surface. By adjusting the AC-EHD force to match the binding affinity of antibodies against the melanoma-associated chondroitin sulphate proteoglycan (MCSP), a commonly expressed melanoma antigen, this platform achieved an average recovery of 84.7% from biological samples. Subsequent staining with anti-BRAF(V600E) specific antibody enabled on-chip evaluation of BRAF(V600E) mutation status in melanoma cells. We believe that the ability of nanoshearing-based capture to enumerate melanoma cells and subsequent on-chip characterisation has the potential as a rapid screening tool while making treatment decisions.

The ERK cascade inhibitors: Towards overcoming resistance

The RAS-ERK pathway plays a major regulatory role in various cellular processes. This pathway is hyperactivated and takes an active part in the malignant transformation of more than 85% of cancers. The hyperactivation is mainly due to oncogenic activating mutations in the pathway's components RAS, RAF and MEK, but also due to indirect mechanisms in cells transformed by other oncogenes. Various inhibitors targeting the different tiers of the cascade have been successfully developed and clinically approved, while some are still undergoing preclinical and clinical evaluation. Treatments with the clinically approved RAF and MEK inhibitors have substantially improved the clinical outcome of metastatic mutated-BRAF melanoma. However, the rapid emergence of drug resistance of initially responsive cancers and limited efficacy towards other cancers has led to only marginal patient benefit. Deciphering the molecular mechanisms underlying intrinsic or acquired resistance is a necessity in order to enhance the treatment efficacy of ERK-addicted cancers. Therefore, many studies in the past 5 years embarked on this campaign, revealing several resistance mechanisms. These include, expression of drug-resistant RAF isoforms, molecular or genetic alterations of active downstream components, overexpression of upstream components of the cascade that can reactivate ERK and other survival-related pathways. The understanding of these molecular resistance mechanisms led to further development of drugs that can overcome drug resistance, including our own effort aiming to prevent the nuclear translocation of ERK without affecting its activation. In this review we will focus on the mechanisms underlying drug resistance and efforts to develop activity-independent, more efficacious, antitumor drugs.

Vemurafenib for the treatment of BRAF mutant metastatic melanoma

Vemurafenib was the first selective BRAF inhibitor licensed in cancer. It is indicated for the treatment of patients affected by advanced melanoma with BRAF V600 mutation. It has shown successful results in terms of efficacy together with a favorable toxicity profile. Other compounds such as the BRAF inhibitor dabrafenib and the immunotherapeutic agent ipilimumab are also approved in the same group of patients. This article reviews the chemistry, pharmacokinetics, pharmacodynamics and clinical development of vemurafenib. Moreover, its efficacy and toxicity are compared with dabrafenib and ipilimumab. A number of trials with vemurafenib alone or in combination with other drugs are also analyzed. These trials will determine the role of vemurafenib in the treatment of BRAF mutant melanoma in forthcoming years.