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.
The immediate molecular mechanisms behind invasive melanoma are poorly understood.,Recent studies implicate microRNAs (miRNAs) as important agents in melanoma and other cancers.,To investigate the role of miRNAs in melanoma, we subjected human melanoma cell lines to miRNA expression profiling, and report a range of variations in several miRNAs.,Specifically, compared with expression levels in melanocytes, levels of miR-211 were consistently reduced in all eight non-pigmented melanoma cell lines we examined; they were also reduced in 21 out of 30 distinct melanoma samples from patients, classified as primary in situ, regional metastatic, distant metastatic, and nodal metastatic.,The levels of several predicted target mRNAs of miR-211 were reduced in melanoma cell lines that ectopically expressed miR-211.,In vivo target cleavage assays confirmed one such target mRNA encoded by KCNMA1.,Mutating the miR-211 binding site seed sequences at the KCNMA1 3′-UTR abolished target cleavage.,KCNMA1 mRNA and protein expression levels varied inversely with miR-211 levels.,Two different melanoma cell lines ectopically expressing miR-211 exhibited significant growth inhibition and reduced invasiveness compared with the respective parental melanoma cell lines.,An shRNA against KCNMA1 mRNA also demonstrated similar effects on melanoma cells. miR-211 is encoded within the sixth intron of TRPM1, a candidate suppressor of melanoma metastasis.,The transcription factor MITF, important for melanocyte development and function, is needed for high TRPM1 expression.,MITF is also needed for miR-211 expression, suggesting that the tumor-suppressor activities of MITF and/or TRPM1 may at least partially be due to miR-211's negative post transcriptional effects on the KCNMA1 transcript.,Given previous reports of high KCNMA1 levels in metastasizing melanoma, prostate cancer and glioma, our findings that miR-211 is a direct posttranscriptional regulator of KCNMA1 expression as well as the dependence of this miRNA's expression on MITF activity, establishes miR-211 as an important regulatory agent in human melanoma.