Some utilize carcinogens, with or without high fat diets, others involve expressing viral proteins (derived from hepatitis B, or Hepatitis C viruses), or expressing genes such as Myc, astrocyte elevated gene 1, E2F1, TGFα or β-catenin, or injection of relevant proteins via hydrodynamic tail vein infection (for review on HCC preclinical models see [48, 83, 84]. The gene discussed is E2F1; the disease is hepatocellular carcinoma.