CDK4 and neoplasm: Meanwhile, 1st released core is internalized by tumor cells and degraded by glutathione (GSH), to realize a 2nd release of Cyclin‐dependent kinase 4/6 inhibitors (CDK4/6i), which induces up‐regulated expression of C‐X‐C motif chemokine ligand 10 (CXCL10) and C‐C motif chemokine ligand 5 (CCL5), and thus a significantly increased tumor infiltration of T cells.