Comparison of the extent of CpG methylation of the GSTP1 sense strand promoter region among various normal and diseased liver tissues1.

1The extent of methylation at each CpG site was analyzed as in Figure 1C: no methylation (no methylation detected); low methylation (50% or less); high methylation (more than 50%).2The CpG sites included in the 5′-end and the 3′-end are described in the text.3The percent of CpG methylation was calculated as the number of methylated CpG sites per category/total CpG sites analyzed×100%.4p value was determined using Student's t test.HCC, hepatocellular carcinoma.