Younger age (P < 0.05), microscopic (P < 0.05) and macroscopic (P < 0.05) lymphatic involvement at diagnosis of primary melanoma were significantly linked to BRAF mutations.
With these results, we are the first to show that long-term melanoma therapy with BRAF inhibitors can prevent further therapeutic success with dacarbazine due to acquisition of cross-resistance.
With the recent developments in novel molecular targeted therapy such as immune-checkpoint blockades, serine/threonine-protein kinase B-Raf, and mitogen-activated protein kinase kinase inhibitors, the prognosis of advanced malignant melanoma has been improving.
With the identification of BRAF mutations found to be present in 50% of melanomas and the clinical success of serine/threonine-protein kinase B-raf inhibitors the prognostic landscape of melanoma has changed considerably.
With the emergence of BRAF(V600E) as a therapeutic target, we investigated intra- and inter-tumor heterogeneity in melanoma using detection of the BRAF(V600E) mutation as a marker of clonality.
With respect to the B-raf protein sequence, the V599E mutation was predicted in 63% of these positive melanomas, followed in frequency by the V599K transition (31%).
With regard to the frequency of V599EBRAF mutations, AM significantly differs from CM (P < or = .0001), which suggests that BRAF mutations distinguish anorectal from cutaneous melanoma at the molecular level.
With increases in our understanding of the human genome and immune system, the treatment armamentarium for melanoma has benefitted from the development and approval of BRAF inhibitors, MEK inhibitors, immune checkpoint modulators via cytotoxic T-lymphocyte antigen-4 blockade, and PD-1 and PD-L1 inhibitors.
While vemurafenib was the first approved BRAF inhibitor for this indication, another selective BRAF inhibitor, dabrafenib, has demonstrated efficacy in patients with BRAF mutant melanoma, including those with active brain metastases and other malignancies.
While under normoxic conditions the expression of glycolysis-related genes showed no correlation with origin or BRAF mutation status, GLUT1 expression was significantly elevated in metastatic and BRAF-V600E mutated melanoma cell lines under hypoxic conditions.
While the use of BRAF and MEK inhibitors, either as a single agent or in combination, improved efficacy in BRAF-mutant melanoma, initial responses are often followed by relapse due to acquired resistance.
While mutations of the BRAF gene are frequent in melanomas on non-chronic sun damaged skin which are prevalent in Caucasians, acral and mucosal melanomas harbor mutations of the KIT gene as well as the amplifications of cyclin D1 or cyclin-dependent kinase 4 gene.
While associated with high rates of toxicity, adverse events are largely manageable with corticosteroids and treatment cessation, in which case patients may continue to benefit even after a limited duration of treatment.Multiple treatment options exist for patients with BRAF V600 mutant melanoma.
While BRAF and MEK inhibitors improve BRAF mutant melanoma patient outcomes, these inhibitors had limited success in other MAPK dysregulated tumors, with insufficient pathway suppression and likely pathway reactivation.
While BRAF inhibitors are initially effective for BRAF-mutant melanoma, no FDA-approved targeted therapies exist for BRAF-inhibitor-resistant BRAF(V600), NRAS mutant, or wild-type melanoma.
Whereas common acquired naevi and melanoma often harbour BRAF mutations, NRAS mutations, or inactivation of NF1, Spitz tumours show HRAS mutations, inactivation of BAP1 (often combined with BRAF mutations), or genomic rearrangements involving the kinases ALK, ROS1, NTRK1, BRAF, RET, and MET.
When used alone or in combination with a specific inhibitor of the BRAF(V600E) oncogene, DHODH inhibition led to a marked decrease in melanoma growth both in vitro and in mouse xenograft studies.
When testing gene lists discriminative of BRAF, NRAS and MAPK alterations, we found that 112 BRAF-specific transcripts were able to distinguish the two immune-related phenotypes already described in melanoma, with the poor phenotype associated mostly with BRAF mutation.
When compared to WT, multivariate analysis of melanoma-specific survival (MSS) identified NRAS mutations as an adverse prognostic factor [hazard ratio (HR) 2.96; P = 0.04] but not BRAF(V600E) mutations (HR 1.73; P = 0.23).