To elucidate the effects of expression of Notch1 on biological behaviors of HCC cell lines, we designed Notch1 siRNAs (si-Notch1) and transfected si-Notch1 into HepG2 and Hep3B cells to interfere with expression of endogenous Notch1. The gene discussed is NOTCH1; the disease is hepatocellular carcinoma.