As another example, the preclinical observation that CDK4/6 inhibition can attenuate NRAS oncogenic signaling when combined with MEK inhibition has led to an undergoing clinical investigation of the synergistic inhibition of CDK4/6 (PD-0332991) and MEK1/2 (selumetinib) in NRAS-mutant melanomas (29). The gene discussed is CDK4; the disease is melanoma.