Eight proteins that had higher expression in BRAFV600E metastatic CM tissue and decreased during BRAFi and MEKi treatment belong to the “positive regulation of MAPK cascade” pathway: CHI3L1, DDT, AKAP12, NDST1, CDON, CTGF, CDH2, and ROBO1. This evidence concerns the gene CHI3L1 and cutaneous mastocytosis.