Study on relationship between abnormal expression of DNA-methyltransferase 3B and hepatocellular carcinogenesis

Objective To explore the relationship between DNA-methyltransferase 3B(DNMT3B)gene and hepatocellular carcinogenesis.Methods Using real-time fluorescent quantitative RT-PCR to analyze the expressions of DNMT1,DNMT3A and DNMT3B in normal liver cell line,pericacinoma cell line and hepatocellular carcinoma cell line respectively.Real-time fluorescent quantitative RT-PCR was also used to confirm the up-regulation of some genes related to tumorgenesis,such as PDCD4 and MBD3 detected by cDNA microarray for DNMT3B RNAi of hepatocellular carcinoma cell line SMMC-7721.Results There was over-expression of DNMTs in hepatocellular carcinoma cell line compared to that in pericacinoma cell line and normal liver cell line,especially the expression of DNMT3B was significantly increased.Conclusion These obtained data indicated that DNMT3B may be involved in hepatocellular carcinogenesis and the regulation for the expression of some tumor suppressor genes related to carcinogenesis by certain mechanism.