Cellular apoptosis is another critical contributor to impaired cell growth and colony formation ability, so here after culturing for 4 days, the apoptosis status in human hepatocellular carcinoma cells HepG2 and SMMC-7721 infected with lentiviruses expressing either Scr-shRNA or KPNA2-shRNA was examined by the annexin V-APC assay followed by flow cytometry (Figure 5A–5B). The gene discussed is APC; the disease is hepatocellular carcinoma.