REN and hepatocellular carcinoma: More importantly, irrespective of the shRNA used, Cdk9 suppression doubled the median survival, thereby reconfirming the role of CDK9 in HCC maintenance (CAGs-rtTA3; TG-Ren.713E mice: 13 d vs. CAGs-rtTA3; TG-Cdk9.421E and CAGs-rtTA3; TG-Cdk9.1260E mice: 26 and 25 d, respectively) (Fig. 3E).