Title : Hepatitis B virus X protein suppresses caveolin - 1 expression in hepatocellular carcinoma through regulating DNA methylation

2. The authors suggested that HBx can induce caveolin-1 gene CpG island methylation, based on their in vitro study using a SMMC-7721 cell line. They also found that 28/33 HCC samples were positive for caveoline-1 gene CpG island methylation. How about the adjacent non-tumor tissues? Since HBx may commonly expressed in the non-tumor tissue, has they seen any caveolin-1 CpG island methylation in specimen derived from the HBV positive non-tumor tissues? Also, it is of informative to compare the methylation statues of caveolin-1 gene CpG island between HBV-positive and HBV-negative HCC tissues.