To examine the efficacy of dual blockade of CDK4/6 and MEK on KRAS mutant CRC cells, cell growth and colony formation were determined after treatment with the MEK inhibitor MEK162 and the CDK4/6 inhibitor palbociclib, using clinically relevant doses of palbociclib [28, 29] and doses optimized to each cell line to maximally display contrast of cell growth between monotherapies and combination therapy (See Supplementary Table S1 and Figure S1). This evidence concerns the gene KRAS and colorectal carcinoma.