Based on the mechanism of the preclinical efficiency of CDK4/6 inhibitor acting on SMARCA4-defective tumors, a phase I study of the CDK4/6 inhibitor Ribociclib (LEE011) was conducted in pediatric patients with rhabdoid tumors harboring SWI/SNF subunits with a high mutation rate [202]. Here, CDK4 is linked to rhabdoid tumor.