Potential role of human DNA-repair enzymes hMTH1, hOGG1 and hMYHalpha in the hepatocarcinogenesis

Abstract

To elucidate role of the three enzymes in hepatocarcinogenesis, hMTH1, hOGG1 and hMYH, mRNA expression were examined by using RT/semi-quantitative real-time PCR and 8-O-HdG levels was studied by HPLC/ECD in HCC and non-tumorous liver tissue of 21 patients with hepatocellular carcinoma (HCC). It was found that the 8-OHdG level in non-tumourous liver tissue was significantly higher than in HCC tissue (P = 0.006), and this was correlated with the degree of inflammation. The hMTH1 expression in HCC tissue was significantly higher than in non-tumorous liver tissue (P = 0.014). Inversely, The hMYH alpha expression was significantly increased (P = 0.039) in non-tumorous liver tissue. No difference was seen in hOGG1 expression in non-tumorous liver and HCC tissue. A significant linear correlation between hMTH1 and hOGG1 expression was found both in HCC tissue (r = 0.809, P < 0.001) and in non-tumorous liver tissue (r = 0.883, P < 0.001). Our findings suggested a reactive rather than pathogenic role of the DNA repair enzymes in the hepatocarcinogenesis.