Search Results (179)

Aldehyde dehydrogenase 2 (ALDH2) is a crucial detoxifying enzyme that eliminates toxic aldehydes. ALDH2 deficiency has been linked to various human diseases, including certain cancers. We have previously reported ALDH2 downregulation in human melanoma tissues. Here, we further investigated the biological significance of ALDH2 downregulation in this malignancy. Analysis of TCGA dataset revealed that low ALDH2 expression correlates with poorer survival in metastatic melanoma. Examination of human metastatic melanoma cell lines confirmed that most had ALDH2 downregulation (ALDH2-low) compared to primary melanocytes. In contrast, a small subset of metastatic melanoma cell lines exhibited normal ALDH2 levels (ALDH2-normal). CRISPR/Cas9-mediated ALDH2 knockout in ALDH2-normal A375 cells promoted tumor growth and MAPK/ERK activation. Given the pivotal role of MAPK/ERK signaling in melanoma and cellular response to acetaldehyde, we compared A375 with ALDH2-low SK-MEL-28 and 1205Lu cells. ALDH2-low cells were intrinsically resistant to BRAF and MEK inhibitors, whereas A375 cells were not. However, A375 cells acquired resistance upon ALDH2 knockout. Furthermore, melanoma cells with acquired resistance to these inhibitors displayed further ALDH2 downregulation. Our findings indicate that ALDH2 downregulation contributes to melanoma progression and therapy resistance in BRAF-mutated human metastatic melanoma cells, highlighting ALDH2 as a potential prognostic marker and therapeutic target in metastatic melanoma. Full article

Melanoma treatment comprised a few treatment choices with insufficient efficacy before the emergence of molecularly targeted medication and immune checkpoint inhibitors, which dramatically improved patient outcomes. B-Rapidly Accelerated Fibrosarcoma (BRAF) and Mitogen-Activated Protein Kinase (MAPK) Kinase (MEK) inhibitors significantly improved survival in BRAF-mutant melanoma and immune checkpoint inhibitors, such as anti-programmed cell death 1 (PD-1) and Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) agents, established new standards of care. Challenges remain, however, including the existence of resistance mechanisms and the reduced efficacy of immune-based therapies in Asian populations, particularly for acral and mucosal subtypes. This review highlights historical and current therapeutic advancements, discusses regional considerations, and explores emerging strategies aiming at globally optimizing melanoma management. Full article

Patients with advanced melanoma who progress on standard-dose ipilimumab (Ipi) + nivolumab continue to have poor prognosis. Studies support a dose–response activity of Ipi, and one promising combination is Ipi 10 mg/kg (Ipi10) + temozolomide (TMZ). We performed a retrospective cohort analysis of patients with advanced melanoma treated with Ipi10 + TMZ in the immunotherapy refractory/resistant setting (n = 6, all progressed after prior Ipi + nivolumab), using similar patients treated with Ipi3 + TMZ (n = 6) as comparison. Molecular profiling by whole-exome sequencing (WES) and RNA-sequencing (RNA-seq) of tumors harvested through one responder’s treatment was performed. With a median follow up of 119 days, patients treated with Ipi10 + TMZ had a statistically significant longer median progression-free survival of 144.5 days (range 27–219) vs. 44 (26–75) in Ipi 3 mg/kg (Ipi3) + TMZ, p = 0.04, and a trend of longer median overall survival of 154.5 days (27–537) vs. 89.5 (26–548). Two patients in the Ipi10 + TMZ cohort had a partial response, and both responders had BRAF V600E mutant melanoma. RNA-seq showed enrichment of inflammatory signatures, including interferon responses in metastases after Ipi10 + TMZ compared to the primary tumor, and downregulated negative immune regulators. Ipi10 + TMZ demonstrated efficacy, including dramatic responses in patients refractory to prior Ipi + anti-PD1. Molecular data suggest a potential threshold of Ipi dose for activation of sufficient anti-tumor immune response, and higher doses are required for some patients. Full article

Irisin is a newly discovered 12 kDa messenger protein involved in energy metabolism. Irisin affects signaling pathways in several types of cancer; however, the role of irisin in metastatic melanoma (MM) has not been described yet. We explored the biological effects of irisin in in vitro models of MM cells (HBL^wt/wt, LND1^wt/wt, Hmel1^V600K/wt and M3^V600E/V600E) capable of the oncogenic activation of BRAF. We treated MM cells with different concentrations of r-irisin (10 nM, 25 nM, 50 nM, 100 nM) for 24 h–48 h. An MTT assay highlighted that r-irisin did not affect the proliferation of MM cells. We subsequently treated MM cells with 10 nM r-irisin, corresponding to the dose exhibiting biological activity in vitro. Irisin reduced the invasive ability of only LND1^wt/wt (p < 0.05), which highly expressed αv gene levels, but did not affect the invasion of BRAF^mut cells. Gelatin zymography analysis showed a reduction in the enzymatic activity of MMP-2 and MMP-9 in BRAF^wt/wt cells treated with 10 nM r-irisin. Moreover, gene expression analysis (qPCR) of MMP-2 and MMP-9 and of the fibrinolytic system (uPAR, uPA and PAI-1) highlighted a crucial role of 10 nM r-irisin treatment in the inhibition of pro-invasive systems in BRAF^wt/wt. In conclusion, our results may suggest a possible differential role of irisin in melanoma cells. Full article

Melanoma is among the most abundant malignancies in the US and worldwide. Ligstroside aglycone (LA) is a rare extra-virgin olive oil-derived monophenolic secoiridoid with diverse bioactivities. LA dose–response screening at the NCI 60 cancer cells panel identified the high sensitivity of the Malme-3M cell line, which harbors a BRAF V600E mutation. Daily oral 10 mg/kg LA exhibited potent in vivo antitumor effects against Malme-3M cells xenograft in a nude mouse model by targeting the BRAF signaling pathway. A human Clariom S microarray analysis of the collected Malme- 3M tumors identified 571 dysregulated genes, with the downregulation of pathways critical for melanoma cells growth and survival. A Western blot analysis of the collected animal tumors further validated the downregulation of the mutated BRAF–MAPK axis, as well as the GPD1 and ELOVL6 expression levels. A histopathological analysis of Malme-3M tumor sections showed extensive focal tumor necrosis in treated mice. An immunofluorescence study of tumor sections showed notable reductions in proliferation marker ki67 and the vasculogenesis marker CD31 in treated tumors. These findings promote LA as a potential nutraceutical lead for the control of the BRAF V600E mutant melanoma. Full article

Melanoma cells remain resistant to chemotherapy with cisplatin (CisPt) and doxorubicin (DOX). The abnormal expression of Receptor-Interacting Protein Kinase 4 (RIPK4) in certain melanomas contributes to tumour growth through the NFκB and Wnt/β-catenin signalling pathways, which are known to regulate chemoresistance and recurrence. Despite this, the role of RIPK4 in response to chemotherapeutics in melanoma has not been reported. In this study, we examined how the downregulation and overexpression of RIPK4 affect the sensitivity of BRAF-mutated melanoma cells (A375 and WM266.4) to CisPt and DOX along with determining the underlying mechanism. Using two RIPK4 silencing methods (siRNA and CRISPR/Cas9) and overexpression (dCas9-VPR), we assessed CisPt and DOX-induced apoptosis using caspase 3/7 activity, annexin V/7AAD staining, and FASC analysis. In addition, qRT-PCR and Western blotting were used to detect apoptosis-related genes and proteins such as cleaved PARP, p53, and cyclin D1. We demonstrated that the overexpression of RIPK4 inhibits, while its downregulation enhances, CisPt- or DOX-induced apoptosis in melanoma cells. The effects of downregulation are similar to those observed with pre-incubation with cyclosporin A, an ABCG2 inhibitor. Additionally, our findings provide preliminary evidence of crosstalk between RIPK4, BIRC3, and ABCG2. The results of these studies suggest the involvement of RIPK4 in the observed resistance to CisPt or DOX. Full article

Background: There are no active treatment options for patients with progressive melanoma brain metastases (MBM) failing immune checkpoint blockade (ICB) and BRAF/MEK inhibitors (BRAF/MEKi). Regorafenib (REGO), an oral multi-kinase inhibitor (incl. RAF-dimer inhibition), can overcome adaptive resistance to BRAF/MEKi in preclinical models. Methods: This is a single-center retrospective case series of patients with refractory MBM treated with REGO plus BRAF/MEKi (compassionate use). Results: A total of 22 patients were identified (18 BRAF-mutant, 4 NRAS^Q61-mutant; 19 with progressive MBM; 11 on corticosteroids). Thirteen BRAF^V600-mutant patients were progressing on BRAF/MEKi at the time of REGO association. BRAF-mutant patients received REGO (40–80 mg once daily) combined with BRAF/MEKi, NRAS-mutant patients were treated with REGO + MEKi (+low-dose BRAFi to mitigate skin-toxicity). Grade 3 TRAE included arterial hypertension (n = 4) and maculopapular rash (n = 3). There were no G4/5 TRAE. In BRAF-mutant patients, overall and intracranial objective response rates (overall ORR and IC-ORR) were 11 and 29%, and overall and intracranial disease control rates (overall DCR and IC-DCR) were 44 and 59%, respectively. In NRAS-mutant patients overall ORR and IC-ORR were 0 and 25% and overall DCR and IC-DCR were 25 and 50%, respectively. The median PFS and OS were, respectively, 7.1 and 16.4 weeks in BRAF-mutant and 8.6 and 10.1 weeks in NRAS-mutant patients. Conclusions: In heavily pretreated patients with refractory MBM, REGO combined with BRAF/MEKi demonstrated promising anti-tumor activity with an acceptable safety profile. In BRAF^V600-mutant melanoma patients, responses cannot solely be attributed to BRAF/MEKi rechallenge. Further investigation in a prospective trial is ongoing to increase understanding of the efficacy. Full article

Background/Objectives: Drug resistance poses a substantial clinical challenge in melanoma treatment, yet the underlying mechanism remains elusive. Here, we report the novel role of laminB1, a nuclear structure protein, in regulating the response of BRAF-mutated melanoma cells to vemurafenib. Results: Our analysis of clinical samples and existing databases highlights the tight correlation between the laminB1 expression level and melanoma progression and prognosis. Notably, we observe that laminB1 expression is upregulated when BRAF-mutated melanoma cells develop resistance to vemurafenib. The knockdown of laminB1 substantially increases the sensitivity of melanoma cells to vemurafenib. Furthermore, we found laminB1 suppression increases cell apoptosis via the escalation of DNA damage in a vemurafenib-dose-dependent manner. Conversely, protective cell autophagy is negatively regulated by laminB1 suppression. Interestingly, this distinct regulation pattern of apoptosis and autophagy by laminB1 cooperatively promotes the response of BRAF-mutated melanoma cells to vemurafenib. Conclusions: Our findings unveil the potential of laminB1 as both a diagnosis marker and a therapeutic target of melanoma. Full article

The incidence of melanoma, the most lethal form of skin cancer, has increased mainly due to ultraviolet exposure. The molecular characterization of melanomas has shown a high mutational burden led to the identification of some recurrent genetic alterations. BRAF gene is mutated in 40–50% of melanomas and its role in melanoma development is paramount. BRAF mutations confer constitutive activation of MAPK signalling. The large majority (about 90%) of BRAF mutations occur at amino acid 600; the majority are BRAF^V600E mutations and less frequently BRAF^{v600K, V600D} and ^V600M. The introduction of drugs that directly target BRAF-mutant protein (BRAF inhibitors) and of agents that stimulate immune response through targeting of immune check inhibitor consistently improved the survival of melanoma BRAF^V600-mutant patients with unresectable/metastatic disease. In parallel, studies in melanoma stage II-III patients with resectable disease have shown that adjuvant therapy with ICIs and/or targeted therapy improves PFS and RFS, but not OS compared to placebo; however, neoadjuvant therapy plus adjuvant therapy improved therapeutic response compared to adjuvant therapy alone. Full article

The combinations of BRAF inhibitor-based targeted therapies with immune checkpoint inhibitors currently represent less common therapeutic approaches in advanced melanoma. The aim of this study was to assess the safety and efficacy of currently available melanoma treatments by conducting a systematic review and network meta-analysis. Four databases were systematically searched for randomized clinical studies that included patients with advanced/metastatic melanoma receiving chemotherapy, immune checkpoint inhibitors, BRAF/MEK inhibitor therapy, or combinations thereof. The primary endpoints were treatment-related adverse events (TRAE), serious adverse events (SAE) of grade ≥ 3 adverse events, therapy discontinuation, progression-free survival (PFS), as well as objective response rate (ORR) and complete response rate (CRR). A total of 63 articles were eligible for our systematic review; 59 of them were included in the statistical analysis. A separate subgroup analysis was conducted to evaluate the efficacy outcomes, specifically in BRAF-positive patients. Triple combination therapy or triple therapy (inhibiting BRAF, MEK and PD1/PDL1 axis) showed significantly longer progression-free survival compared to BRAF + MEK combination therapies (HR = 0.76; 95% CI 0.64–0.9), but similar objective and complete response rates in BRAF-mutated melanoma. This safety analysis suggests that triple therapy is not inferior to combined immune checkpoint inhibitors (ICI) and BRAF/MEK therapies in terms of serious adverse events and therapy discontinuation rates. However, monotherapies and BRAF/MEK combinations showed notable advantage over triple therapy in terms of treatment-related adverse events. Combination strategies including BRAF/MEK-targeted therapies with ICI therapies are effective first-line options for advanced, BRAF-mutant melanoma; however, they are associated with more frequent side effects. Therefore, future RCTs are required to evaluate and identify high-risk subpopulations where triple therapy therapies should be considered. Full article

Adjuvant radiation therapy (ART) for macroscopic regional nodal cutaneous melanoma has evolved. A significant step was the discovery of targeted therapies, particularly towards V600E-mutated melanoma, and immunotherapy under its different kinds. Prior to this, the defining trial was the Australia and New Zealand Melanoma Trials Group (ANZMTG) 01.02/Trans-Tasman Radiation Oncology Group (TROG) 02.01 phase III trial that showed that ART using three-dimensional conformal radiotherapy (3DCRT) decreased in-field recurrence by 50% (48 Gray (Gy) in 20 fractions). After the advent of systemic therapies, a trial of the combination targeted therapy of dabrafenib plus trametinib toward BRAF V600-mutant nodal cutaneous melanoma showed that all 35 patients achieved a pathological response. Radiotherapy (RT) was found to be safe to give with concurrent combination therapy. A retrospective immunotherapy study found that in 71 patients that received ART after a first recurrence, further in-field recurrence significantly decreased (p = 0.01). For those tumours that do recur in-field, there are now competing therapies like Talimogene laherparepvec or T-VEC. Generally, ART is now used at the first recurrence. The challenge now is to find which melanomas are truly radiosensitive if ART is to have any future role in this scenario. Full article

Melanoma is an aggressive cancer characterized by rapid growth, early metastasis, and poor prognosis, with resistance to current therapies being a significant issue. BRAF mutations drive uncontrolled cell division by activating the MAPK pathway. In this study, A375 and FO-1, BRAF-mutated melanoma cell lines, were treated for 4–5 months with RAF inhibitor dabrafenib or AZ628, leading to drug resistance over time. The resistant cells showed altered molecular signatures, with differences in cell cycle regulation and the propensity of cell death. Dabrafenib-resistant cells maintained high proliferative activity, while AZ628-resistant cells, especially A375 cells, exhibited slow-cycling, and a senescent-like phenotype with high susceptibility to ferroptosis, a form of cell death driven by iron. Antiretroviral drugs doravirine and cabotegravir, known for their effects on human endogenous retroviruses, were tested for their impact on these resistant melanoma cells. Both drugs reduced cell viability and colony formation in resistant cell lines. Doravirine was particularly effective in reactivating apoptosis and reducing cell growth in highly proliferative resistant cells by increasing tumor-suppressor proteins p16^Ink4a and p27^Kip1. These findings suggest that antiretroviral drugs can influence apoptosis and cell proliferation in RAF-inhibitor-resistant melanoma cells, offering potential therapeutic strategies for overcoming drug resistance. Full article

Melanoma is a highly aggressive type of skin cancer. Metastatic melanoma tumors have historically featured a particularly poor prognosis and have often been considered incurable. Recent advances in targeted therapeutic interventions have radically changed the landscape in metastatic melanoma management, significantly increasing the overall survival of patients. Hyperactive BRAF is the most common mutational event found in metastatic melanoma and its inhibition has proven to be a successful approach in a number of patients. Unfortunately, initial tumor retreat is followed by relapse in most cases, highlighting the elusiveness of finding a widely effective treatment. Melanoma tumors often carry a particularly high number of mutations in what is known as a high level of inter- and intra-patient tumor heterogeneity, driving resistance to treatment. The various mutations that are present in these tumors, in addition to impacting the root cause of the malignancy and the potential for therapeutic interventions, have also been known to arise during tumor clonal evolution leading to the establishment of drug resistance, a major issue in melanoma management. Full article

Background: When monotherapy with PD-1 inhibitors in metastatic melanoma fails, there are currently no standard second-line choices. In case of the unavailability of clinical trials, ipilimumab represents a possible alternative treatment. Methods: We collected data of 44 patients who received ipilimumab after the failure of PD-1 inhibitors from July 2017 to May 2023 at our Institute. Overall survival (OS), progression-free survival (PFS), and post-progression survival (PPS) based on BRAF or NRAS mutation status, sex, and the presence of brain metastases were estimated using the Kaplan–Meier method. Cox regression was used to evaluate independence in multivariate analysis. The objective response rate (ORR) was estimated based on RECIST 1.1. Results: Among the 44 patients enrolled in this study, 28 BRAF-wildtype, 9 BRAF-mutated, and 7 NRAS-mutated patients were identified. OS analysis showed a significant difference between wildtype and BRAF- or NRAS-mutated patients: 23.2 months vs 5.3 and 4.59, respectively, p = 0.017. The presence of brain metastases and BRAF or NRAS mutation were independent factors for mortality in multivariate analysis. Conclusions: In case of failure to enroll patients in innovative clinical trials, second-line ipilimumab still represents an effective therapy in patients with metastatic wildtype melanoma and in the absence of brain metastases. Full article

Background: Nivolumab plus ipilimumab (nivo/ipi) combination therapy is highly effective in treating advanced melanoma, but serious immune-related adverse events (irAEs) are prevalent. The overall response rate (ORR) of the BRAF inhibitor plus MEK inhibitor (BRAFi/MEKi) combination therapy for BRAF^V600-mutant advanced melanoma surpasses that of immune checkpoint inhibitors (ICIs). However, the OS and PFS of BRAFi/MEKi combination therapy are inferior to those of ICIs. Methods: We retrospectively evaluated 22 melanoma patients treated with nivo/ipi therapy and 13 patients treated with encorafenib plus binimetinib (enco/bini) between November 2018 and July 2023. Results: The ORR of nivo/ipi for metastatic melanoma patients was significantly higher in the first-line cohort [60.0% (95% CI: 31.2–83.3%)] than in the second-line or beyond cohort [8.3% (95% CI: 0–37.5%)], whereas the ORR of enco/bini was comparable between the first-line cohort [75.0% (95% CI: 28.9–96.6%)] and the second-line or beyond cohort [77.8% (95% CI: 44.3–94.7%)]. The median PFS of nivo/ipi significantly improved in the first-line cohort [7.7 months (95% CI: 2.0–11.9)] compared to the second-line or beyond cohort [2.3 months (95% CI: 0.5–6.0)] (p = 0.0109). In addition to efficacy, the incidence of grade 3 or greater AEs was comparable in the first-line and second-line or beyond cohorts. Conclusions: Although our present data are based on a small number of cases, they suggest that nivo/ipi should be administered as the first-line therapy for the treatment of BRAF^V600-mutant metastatic melanoma, rather than enco/bini, aligning with findings from previous clinical trials. Full article