Importantly, all cells expressing progenitor cell markers (AFP, A6, and K19) that were found in the HCC of AAV8-Tbg-Cre-injected mice were GFP positive, and therefore most likely derived from malignant hepatocytes that had undergone a process of dedifferentiation and acquisition of progenitor cell marker expression, but not from bona fide progenitor or biliary compartments. The gene discussed is AFP; the disease is hepatocellular carcinoma.