Figure 1

Analysis of DNA methylation in WNA HCC by two PCR methods. (A) Representative Methylation-Specific PCR for 6 of the 11loci on 5 different matching pairs of hepatocellular carcinomas and non-tumorous livers. U: PCR with primers for unmethylated DNA, M: PCR with primers detecting methylated DNA. (B) Representative examples of combined bisulfite restriction analysis (COBRA) performed on 7 pairs of hepatocellular carcinomas and corresponding non-tumorous livers on three different loci. The smaller bands beneath the larger ones represent digested (i.e. methylated for BstUI and unmethylated for HpHI restriction enzymes) alleles. N, noncancerous liver; T: livertumor, C: controls, C- : native DNA from WI38 fibroblasts in culture, C+: SssI CpG methylase-treated DNA from the same cells. Ratio of undigested/digested quantified with ImageJ 1.38 Instrument software integrated (Yang et al., [75]).