AFP and hepatocellular carcinoma: Infection of Ad-AFpg-DN-PP2Acα only triggered apoptosis and G2/M cell cycle arrest in AFP-positive HepG2 and Hep3B cells, but had no effect in AFP-negative L-02 or SK-Hep-1 cells, indicating that specific expression of DN-PP2Acα driven by the AFpg promoter selectively induced apoptosis and cell cycle arrest in AFP-positive HCC cells.