The silence of MUC2 mRNA induced by promoter hypermethylation associated with HBV in Hepatocellular Carcinoma

BACKGROUND: To evaluate the promoter methylation status of MUC2 gene and mRNA expression in patients with hepatocellular carcinoma. METHODS: We analyzed MUC2 methylation by MSP, and MUC2 mRNA by real-time PCR in 74 HCC. RESULTS: MUC2 mRNA were lower in HCC tissues (Mean (-ΔCt) = −4.70) than that in Non-HCC tissues (Mean (-ΔCt) = −2.98). Expression of MUC2 was elevated in only 23 (31.08%) of the 74 HCC patients. MUC2 promoter was hypermethylated in 62.2% (46/74) of HCCs, and in only 18.9% (14/74) of non-tumor samples. MUC2 mRNA were lower in HCC patients with hypermethylation (Mean (-ΔΔCt) = −2.25) than those with demethylation (Mean (-ΔΔCt) = −0.22), and there is a decreased tendency for MUC2 mRNA in HCC patients with promoter hypermethylation (p = 0.011). There was a significantly correlation found between MUC2 mRNA and HBV and AFP in HCC. The loss of MUC2 mRNA and hypermethylation could be poor prognostic factors. After treated by 5-Aza-CdR and TSA, we found that MUC2 mRNA induced significantly in 7721, Huh7 and HepG2 cells. CONCLUSION: The results suggested that MUC2 mRNA silenced by promoter hypermethylation is associated with high levels HBV in HCC.