CDK6 and acute promyelocytic leukemia: To monitor the dynamic change of CDK6 expression in non-APL AML patients in different clinical stages, we tested CDK6 expression in 11 paired patients with available follow-up data at first diagnosis, complete remission (CR), and refractory remission (RR) time (de novo vs. CR: p = 0.002; RR vs. CR: p = 0.0086, respectively) (Figure 2C).