TP53 and hepatocellular carcinoma: Mice that lose Trp53 and Mad2l1 in hepatocytes (promoted by Alb-Cre) initially develop regeneration nodules, a sign of on-going liver repair, then hepatocellular carcinoma, a benign liver tumor and finally hepatocellular carcinoma, an aggressive liver cancer resulting in death between 12–15 months of age.