In addition, from the PPI sub-network of the genes adjacent to the aberrant DNA methylation sites, we found that among the key genes with a gene node degree greater or equal to 10, MYC [19], EIF4E [20], CDK4 [21] and TGFB1 [22] could stimulate the pathogenesis of liver cancer. This evidence concerns the gene TGFB1 and liver cancer.