RAF1 and cancer: While the efficacy of BRAF inhibitors has been demonstrated in other cancers such as melanoma4 and non-small-cell lung cancer,5 their effectiveness remains limited as monotherapy for BRAF V600E-mutant mCRC,6 due to reactivation of the mitogen-activated protein (MAP) kinase signaling pathway by other RAF proteins such as CRAF and epidermal growth factor receptor (EGFR) overexpression.7