Abstract: BACKGROUND AND AIM: To determine whether the mRNA expressions of hMLH1 and hMSH2 genes involved in mismatch repair are associated with the risk of ESCC. MATERIALS AND METHODS: 112 patients with newly diagnosed, untreated ESCC were recruited in Huai'an county. Esophageal cancer tissues and tissues adjacent to the tumors were collected to determine the mRNA levels of hMLH1 and hMSH2 genes by quantitative real-time reverse transcription-PCR using SYBR Green I with β-actin as an internal control. t-test and logistical regression analysis were used to test the differences of gene expression between cancer tissues and tissues adjacent to the tumors. RESULTS: Compared with tissues adjacent to the tumors, the relative expression level of hMSH2 was significantly lower in esophageal cancer tissues (P=0.010, t-test). The conditional logistic regression analysis showed that the increased risk for esophageal cancer was significantly associated with decreased expression of hMSH2 (OR=1.311, 95％ CI: 1.075~1.599). CONCLUSION: Reduced expression of hMSH2 was significantly associated with risk for ESCC, suggesting this might be important for the early progression of ESCC in Huaian of China.

Key words: mismatch repair, gene expression, quantitative real time PCR, esophageal squamous cell carcinomas