Previous studies have suggested that elevated neutrophil-to-lymphocyte ratio (NLR) is prognostic for worse outcomes in patients with a variety of solid cancers, including those treated with immune checkpoint inhibitors.,This was a retrospective analysis of 97 consecutive patients with stage IV melanoma who were treated with nivolumab.,Baseline NLR and derived (d) NLR were calculated and, along with other characteristics, correlated with progression-free survival (PFS) and overall survival (OS) in univariate and multivariate analyses.,The best cutoff values for NLR and dNLR were derived using Cutoff Finder software based on an R routine which optimized the significance of the split between Kaplan-Meier survival curves.,In univariate analysis, increasing absolute neutrophil count (ANC), NLR, dNLR and lactate dehydrogenase (LDH) (continuous variables) were all significantly associated with OS.,Only NLR (hazard ratio [HR] = 2.85; 95% CI 1.60-5.08; p < 0.0001) and LDH (HR = 2.51; 95% CI 1.36-4.64; p < 0.0001) maintained a significant association with OS in multivariate analysis.,Patients with baseline NLR ≥5 had significantly worse OS and PFS than patients with NLR < 5, as did patients with baseline dNLR ≥3 versus < 3.,Optimal cut-off values were ≥ 4.7 for NLR and ≥ 3.8 for dNLR.,Using this ≥4.7 cut-off for NLR, the values for OS and PFS were overlapping to the canonical cut-off for values, and dNLR< 3.8 was also associated with better OS and PFS.,Both Neutrophil-to-lymphocyte ratio (NLR) and derived (d) NLR were associated with improved survival when baseline levels were lower than cut-off values.,NLR and dNLR are simple, inexpensive and readily available biomarkers that could be used to help predict response to immunotherapy in patients with advanced melanoma.,The online version of this article (10.1186/s40425-018-0383-1) contains supplementary material, which is available to authorized users.
We describe a mechanism of tumorigenesis mediated by kinase-dead BRAF in the presence of oncogenic RAS.,We show that drugs that selectively inhibit BRAF drive RAS-dependent BRAF binding to CRAF, CRAF activation, and MEK-ERK signaling.,This does not occur when oncogenic BRAF is inhibited, demonstrating that BRAF inhibition per se does not drive pathway activation; it only occurs when BRAF is inhibited in the presence of oncogenic RAS.,Kinase-dead BRAF mimics the effects of the BRAF-selective drugs and kinase-dead Braf and oncogenic Ras cooperate to induce melanoma in mice.,Our data reveal another paradigm of BRAF-mediated signaling that promotes tumor progression.,They highlight the importance of understanding pathway signaling in clinical practice and of genotyping tumors prior to administering BRAF-selective drugs, to identify patients who are likely to respond and also to identify patients who may experience adverse effects.,► BRAF activates ERK but in some circumstances BRAF inhibitors can induce tumor growth ► BRAF inhibitors drive BRAF-CRAF binding, activating ERK in cells with oncogenic RAS ► Kinase-dead mutants of BRAF have the same effect as BRAF inhibitors ► Oncogenic RAS and kinase-dead BRAF cooperate to induce melanoma in mice