CDK2 and Miyoshi myopathy: As CDK2 is one of the key kinases controlling G1/S transition and DNA replication and p21 is a critical regulator of CDK2, we measured these two proteins and found that tigecycline markedly decreased the levels of CDK2 and p21 in three MM cell lines RPMI‐8226, NCI‐H929, and U266 (Figure 2B).