The Detection And Early Diagnosis Of P16 Gene Promoter Methylation In Stool Of Patients With Colorectal Cancer

Objective: To study p16 gene DNA methylation change in fecal shedding cells of colorectal cancer,in order to evaluate the possibility of methylation analysis of p16 gene in stool for screening early colorectal cancer(CRC).Method: The clinical specimens were provided on the First Affiliated Hospital of Guangxi Medical University from March 2007 to September 2007.The selected object included the 61 patients of colorectal cancer,27 cases of adenomas and 20 cases of nomal man.Using the method of methylation-specific PCR to analysis the p16 gene methylation Situation and Using methylation-specific PCR analysis their change and expression of p16 gene methylation.Results:Methylated.p16.gene.occurred.in.77.0%(47/61),59.3%(16/27),5.0%(1/20) of patients with colorectal cancer,adenomas and nomal.The sensitivity and specificity of p16 gene methylation assay for colorectal cancer was 82.1% And 80.0%,The p16 gene methylation-positive rate of the colorectal cancer had no significant relationship.with the age,sex and tumor site of the colorectal cancer patients.But the p16 gene methylation-positive rate of the colorectal cancer had significant relationship.with the Dukes staging of the tumor,the degree of differentiation and lymph node metastasis.Conclusion: The p16 gene methylation occurred in the early stages of colorectal cancer.Analysis of fecal p16 gene methylation is expected to serve as a new early detection way for colorectal cancer or a new screening tool for individuals at high-risk of developing colorectal cancer.