CDK4 and hepatocellular carcinoma: To further characterize the related genetic pathway affected by 5-fluorouracil and pirarubicin involving the miR-21-mediated program in HCC cells, we examined the associated target genes including p-AKT, AKT, p-GSK3β, GSK3β, cyclin D1, cyclin E1, CDK2, and CDK4.