The combination of the MEK and CDK4/6 inhibitors trametinib (3 mg/kg QOD) and palbociclib (100 mg/kg QD) using oral gavage yielded significantly greater tumor growth inhibition in murine xenografts of the KRAS mutant Lovo cell line compared to vehicle-treated controls or treatment with monotherapy of each drug alone (see Figure 5A). Here, CDK4 is linked to neoplasm.