Most CRC patients are not benefited from immunotherapy, including ICBs, due to the increase of immunosuppressive cells (such as Treg cells) and the low abundance of PD-L1.37 It was found that, inhibition of CDK4/6 could enhance the susceptibility of CT26 tumors to ICBs (Fig. 5a). This evidence concerns the gene CD274 and colorectal carcinoma.