Hypermethylation Of RASSF1A,HIC1 And P73 Genes In Hepatocellular Carcinomas

Objective To evaluate the status of promoter hypermethylation of RASSF1A, HICl and p73 genes in hepatocellular carcinoma. Methods Fourty cases of hepatocellular carcinomas and corresponding nontumor tissues were collected from patients of hepatic resection. Two healthy liver tissues derived from donors of liver transplantation. Methylation specific PCR was used to study the frequence of the promoter hypermethylation of RASSF1A, HICl and p73 genes in these specimens. Results The promoter hypermethylation of RASSFIA is 36 (90%) cases and 29 (72.5%) cases respectively in 40 cases of tumor tissues and corresponding nontumor tissues, and there is statistical difference between of them (P<0.05). Hypermethylation of HICl is 31 (77.5%) cases and 28 (70%) cases individually in 40 cases of tumor tissues and corresponding nontumor tissues. The aberrant methylation of p73 is 5% in tumor tissues, and in corresponding nontumor tissues no hypermethylation is found. There is the methylation of one gene at least in all tumor tissues of HCCs, in which of them 11 (27.5%) cases have one gene methylation and 29 (72.5%) cases have two genes methylation in common. But no cases have three genes promoter methylation in HCCs. There is the methylation of one gene at least in 36 (90%) cases of 40 nontumor tissues of HCCs. 15 (37.5%) cases have only one gene promoter methylation in 40 nontumor tissues of HCCs. 21 (52.5%) cases have two gene promoter methylation all at once in 40 nontumor tissues of HCCs. At the same time no cases have three genes promoter methylation together. There is statistical difference between the frequency hypermethylation of RASSFIA, HICl and p73 gene individually in tumor tissues of HCCs. There is no statistical difference in the frequency of RASSF1A and HICl gene methylation in nontumor tissues of HCCs, but is significant difference in frequency of RASSFIA and p73 gene, HICl and p73 gene in nontumor tissues. There is also no statistical correlation between the methylation of RASSFIA, HICl and p73 gene. There is aberrant methylation in theliver tissues from two normal healthy men. Conclusion The aberrant methylation of RASSFIA and HICl gene promoters are prevalent in HCCs. There could be some correlation between methylation of RASSFIA, HICl genes with tumorigenesis of HCCs. But hypermethylation of p73 gene is rare in HCCs. So there could be absent of immediate correlation between hypermethylation of p73 with tumorigenesis of HCCs.