RB1 and neoplasm: Preclinical studies have shown that CDK4/6 inhibitors dephosphorylate RB, inhibit the activation of the transcriptional repressor complex RB-E2F, and downregulate the expression of the DNA methyltransferase DNMT1, enhancing the activation of cytotoxic cells and improving the antigen presentation of tumor cells (Goel et al., 2017; Schaer et al., 2018; Bai et al., 2023).