The Study On Methylation Of HMLH1 Gene In Sporadic Colorectal Cancer

Purpose: To investigate the action of CPG island methylation of hMLH1 in sporadic colorectal cancer and to study the relationship between hMLH1 methylation and clinical informationMethods: We use Methylation specific PCR(MSP)to study the methylation o hMLH1 in 40 cases of sporadic colorectal tumor ,21case of colorectal adenomas and 14 normal colorectal mucosaResults: there were 23 cases be detected methylation of hMLH1 gene promoter among 40 colorectal cancer(57.5%);4 cases happened methylation among 21 cases colorectal adenomas(19%).And there was no cases happened methylation in normal cases .The rate of hMLH1 methylation in sporadic colorectal cancer significantly higher than colorectal adenoma and normal mucosa.(P<0.05) The rate of hMLH1 methylation in right-side colon (83.3%)was significantly higher than left-side colon(36.4%)(P<0.05)。There was no significantly correlation between methylation of hMLH1 and patients age gender tumor gross type lymph node metastasis distant metastasis and Dukes stage .Conclusion: (1) There exists methylation of hMLH1 gene in sporadic colorectal tumor. The methylation of hMLH1 gene may be involved the carcinogenensis of sporadic colorectal cancer(2) Methylation of hMLH1 had no thing to do with patients age tumor gross lymph mode metastasis and Dukes stage。The rate of hMLH1 Methylation in right-side colon was significantly higher than left-side colon.(3) Methylation of hMLH1 gene exists in the colorectal precancerous lesions and it maybe one of the early events in the occurrence of sporadic colorectal cancer.