SFRP1 and hepatocellular carcinoma: 20 HCC-associated genes (p16, RASSF1A, GSTP1, p14, APC, RUNX3, SOCS1, CDH1, p15, WIF1, PRDM2, SFRP1, RARβ, p73, hMLH1, DLC1, p53, SPINT2, OPCML and WT1) hypermethylation showed significant evidences between HCC tumor tissues and adjacent tissues to the risk of HCC.