NANOG and hepatocellular carcinoma: Concurrently, expression of HBx protein of HBV in HepG2 hepatoma cells greatly enhanced the abundance of the pluripotency transcription factors such as Oct-4, Nanog, and Klf-4, as well as the “stemness”-associated markers EpCAM and β-catenin (Arzumanyan et al., 2011).