Expression of Mismatch Repair Gene hMLH1 and hMSH2 in Colorectal Carcinoma and Its Significance

[Purpose] To investigate the expression of mismatch repair gene human mutl homolog 1(hMLH1) and human mutl homolog 2(hMSH2) in colorectal carcinoma and its significance.[Methods] A total of 85 pathologically proved patients with colorectal carcinoma undergoing surgical resection were included in the study.All the patients did not undergo preoperative chemotherapy or radiotherapy.The expression of hMLH1 and hMSH2 protein was detected by immunohistochemical method.[Results] The loss rate of hMSH2 and hMLH1 expression in cancer tissue was 69.4%(59/85),78.8%(67/85) respectively.The loss rate of hMSH2 expression in patients with T 1,T 2,T 3,T 4 was 50.0%,43.8%,71.1% and 82.8% respectively.The loss rate of hMSH2 expression increased with T stage increasing(χ 2 =11.037,P=0.012).The loss rate of hMSH2 expression in patients with lymph node metastases was 88.57%(31/35),but 56.0%(28/50)in patients without lymph node metastases with significant difference(χ 2 =10.287,P=0.001).The loss rate of hMLH1 expression was correlated to tumor differentiation and T stage,but not correlated to gender,age,tumor site,N stage and M stage.[Conclusion] Loss expression of hMLH-1 and hMSH-2 protein exists in colorectal carcinoma.Expression loss of hMLH-1 and hMSH-2 protein correlates to tumor differentiation and T stage.Combined detection of hMLH-1 and hMSH-2 expression might be useful for evaluating prognosis of colorectal cancer.