BRAF and melanoma: BRAF is a serine/threonine protein kinase which stimulates the mitogen-activated protein kinases/extracellular signal-regulated kinase (MAPK/ERK) signaling pathway 12; about 50% of total melanomas harbors activating mutations of BRAF, in over 90% of cases being the V600E mutation, i.e., the mutation of valine 600 to glutamic acid 13,14.