Abstract
Recent therapeutic advances have improved melanoma patientś clinical outcome. Novel therapeutics targeting BRAF, NRAS and cKit mutant melanomas are widely used in clinical practice. However therapeutic options in NRAS(wild-type) /BRAF(wild-type) /cKit(wild-type) melanoma patients are limited. Our study shows that gene copy numbers of members of the MAPK signaling pathway vary in different melanoma subgroups. NRAS(wild-type) /BRAF(wild-type) melanoma metastases are characterized by significant gains of MAP2K1 (MEK1) and MAPK3 (ERK1) gene loci. These additional gene copies could lead to an activation of the MAPK signaling pathway via a gene-dosage effect. Our results suggest that downstream analyses of the pMEK and pERK expression status in NRAS(wild-type) /BRAF(wild-type) melanoma patients identify patients that could benefit from targeted therapies with MEK and ERK inhibitors.