Association of RASSF1A hypermethylation with risk of HBV/HCV-induced hepatocellular carcinoma: A meta-analysis.

Background: Researchers have discovered a large number of DNA methylation patterns in human cancer. These cancer-specific methylation patterns can provide information for the diagnosis, treatment, and prognosis of cancer. Methylation studies can find new biomarkers based on epigenetic analysis and apply these biomarkers to clinical oncology. Many studies on the association between RAASF1A methylation status and susceptibility to hepatitis B virus (HBV)/hepatitis C virus (HCV)-induced hepatocellular carcinoma (HCC) have reached controversial conclusions. Hence, the current review comprehensively assessed the correlation between Ras association domain family 1A (RASSF1A) methylation and the risk of the HCV/HBV-induced HCC.

Methods: The appropriated publications were extracted in EMBASE, PubMed, Web of Science, Cochrane Library, and China National Knowledge Infrastructure databases using STATA 5.0 software. The odds ratios (ORs) with 95 % confidence interval (95 % CI) of RASSF1A methylation were computed.

Results: A total of 1015 HBV/HCV-related HCC samples, 124 non-HBV/HCV-related HCC (NBNC-HCC) samples, and 1225 nontumorous controls were extracted and examined in this research. The frequency of the methylated RASSF1A in the HBV/HCV-related tumor cases displayed a significantly increased OR compared with the overall nontumor samples (OR = 19.372, 95 % CI = 11.060-33.931, P = 0.000). The frequency of the methylated RASSF1A in HBV/HCV-related neoplasm cases displayed a significantly increased OR compared with the non-HBV/HCV-related neoplasm (NBNC-neoplasm) samples (OR = 2.150, 95 % CI = 1.398-3.308, P = 0.000). Compared with normal, chronic hepatitis B or C, cirrhosis, and paracancerous samples, the pooled OR of the RASSF1A promoter methylation in the HBV/HCV-induced HCC samples was 62.785(95 % CI = 35.224-111.909), 25.07 (95 % CI = 13.85-45.36), 6.89 (95 % CI = 3.33-14.264) and 9.02 (95 % CI = 0.91-89.80), respectively. The rate of RASSF1A hypermethylation was robustly correlated with tumor size and vascular invasion, and the pooled OR was 0.346 (95 % CI = 0.210 - 0.569) and 0.081 (95 % CI = 0.022 - 0.303), respectively.

Conclusion: Results showed robust associations between RASSF1A gene methylation in promoter region and enhanced HBV/HCV-related HCC susceptibility, thereby revealing that RASSF1A methylation status may serve as an important indicator for HCC oncogenesis.