Abstract:Objective:To investigate aberrant methylation in the promoter area of p16 gene and p16 protein expression in human pancreatic carcinoma and in the corresponding tumor-adjacent tissues, and evaluate their role in the carcinogenesis and progression of tumor and its clinical significance.
Methods :Immunohistochemistry and MSP(methylation-specific PCR) were performed on 46 samples of pancreatic carcinoma and their corresponding tumor-adjacent tissue specimens for p16 and its methylation.
Results:Expression rate of p16 protein was 41.3%(19/46) in pancreatic carcinomas, 95.7%(44/46) in corresponding tumor-adiucent tissues. Through MSP, the methylation rate in pancreatic carcinomas was 39.1%.No gene methylation was found in 19 cases expressing p16 protein.p16 gene methylation was closely related to p16 protein expression in pancreatic carcinoma(P<0.05). The expression of p16,the aberrant methylation in the promoter area of p16 gene were no relationship with clinicopathological characteristics, such as tumor size, patient′s sex and age (P>0.05); but were significantly related to the PTNM staging, histological differentiation, distant metastasis and lymph node metastasis(P<0.05).
Conclusions:Methylation in the promoter of p16 gene and p16 protein expression were associated with the development of pancreatic carcinoma and could be used as a putative prognostic indicator for malignancy.