To this end, although Sulfopin and Palbociclib had limited single-agent efficacy in the RB-proficient mouse model, the combination of Sulfopin and the two CDK4 inhibitors nearly entirely suppressed tumor growth, with 2/7 PDOX tumors achieving a complete remission (Fig. 6g, h, Supplementary Fig. 9a, b). This evidence concerns the gene RB1 and neoplasm.