KRAS and melanoma: Through decades of research, several MEK1/2 inhibitors have been proved effective in combined therapies for BRAF V600E mutation melanoma.9 Nevertheless, because of the high gain drug-resistant rate, MEK1/2 inhibitors play an affiliated role in combination with BRAF inhibitors in BRAF V600E mutant melanoma.10 Moreover, they are generally less effective in BRAF WT and/or KRAS mutant tumors.