CDK9 and hepatocellular carcinoma: As shown in Figure 1, HCC cell lines expressed lower level of miR‐206 (HLE, P = 0.0024; HepG2, P = 0.0220; Bell7402, P = 0.0029) and higher level of CDK9 mRNA (HLE, P = 0.0101; HepG2, P = 0.0083; Bell7402, P = 0.0334) and protein (HLE, P = 0.0047; HepG2, P = 0.0049; Bell7402, P = 0.0441) compared to L02 cells, indicating that there was an inverse relationship between the expression of CDK9 and miR‐206.