CDK4 and neoplasm: It was reported that cell cycle, SHP2, MYC, and mTOR were among the key pathways for cell fitness by CRISPR/Cas 9 knockout screening with the KRAS G12C inhibitor MRTX849, and the combination of the KRAS G12C inhibitor with the CDK4/6 inhibitor palbociclib demonstrated more tumor regression in xenograft tumor models than either single agent alone [6].