We set out to examine the correlation between the expression of full-length, C-terminal truncated HBx and the well-document functional liver CSC marker CD133 in a panel of immortalized normal liver (MIHA and LO2) and HCC cell lines (QSG7701, BEL7402, H2P, H2M, PLC8024, Hep3B, Huh7, HepG2, SNU182 and SNU475) in the absence or presence of HBV background by qRT-PCR and flow cytometry. The gene discussed is PROM1; the disease is hepatocellular carcinoma.