CLDN3 and hepatocellular carcinoma: Complete or partial methylation was detected in 6 HCC cell lines with absent expression of CLDN3 (HepG2, Hep3B, Huh7, Bel7404, SNU398, and PLC5), whereas no or weak methylation was detected in other 3 HCC cell lines (Huh1, Huh6, and SNU449) and 4 normal liver tissues with CLDN3 expression (Fig. 2B).