Trilaciclib is a small molecule, a short-acting CDK4/6 inhibitor with BM protection and potential anti-tumor effects, which can induce HSC proliferation in the BM to temporarily and reversibly stagnate the G1 phase, protect them from damage during chemotherapy, help them to recover more quickly from hematopoiesis, and enhance anti-tumor immunity [169, 170]. This evidence concerns the gene CDK4 and neoplasm.