Unlike other carcinogens, DEN does not lead to an early elevation in α-fetoprotein (AFP), a marker of immature hepatocytes (hepatoblasts) and purported hepatic progenitor cells (HPC) [24–27]; instead, transformed AFP-positive hepatocytes appear in DEN-treated livers only later and are followed by the development of AFP-positive HCC [28]. This evidence concerns the gene AFP and hepatocellular carcinoma.