Aberrant Methylation Of NPTX2 Gene Related To Pancreatic Carcinoma

Objective:To discover Molecular markers of pancreatic neoplasia,we analyzed aberrant methylation of NPTX2 gene in pancreatic neoplasia so that we could find the relationship between the aberrant methylation and pancreatic neoplasia. Methods:Firstly,We use qRT-PCR and QMSP to detect the difference of the NPTX2 mRNA expression and methylation in primary pancreatic carcinoma tissues and paraneoplastic tissues. Then we could find the relationship between the aberrant methylation and mRNA expression of NPTX2.Secondly, we analyzed the changes in NPTX2 gene expression of two pancreatic cancer cell lines after treatment with the demethylating agent 5Aza-dC.Thirdly,we have mapped the methylation status of the NPTX2 promoter, using sequencing the production of MSP in pancreatic cancer cell line and in the whole blood DNA from the people without evidence of pancreatic disease.as a control.At last, whole blood DNA and fecal DNA methylation of patients with pancreatic cancer was quantified using QMSP as well as the DNA from patients with chronic pancreatitis and people without evidence of pancreatic disease.Results:â‘ The RQ of the 10 paraneoplastic tissues is higher than that of the 8 primary pancreatic carcinoma tissues. In addition,the result of QMSP indicated that the methylation index(MI) of the 8 primary pancreatic carcinoma tissues is higher than that of the 10 paraneoplastic tissues.â‘¡The RQ of the PANC-1 treated by 5Aza-dC was higher than that before.And the RQ of the ASPC1 treated by 5Aza-dC was also higher than that before.â‘¢Through sequencing the products of MSP,we found that the promoter region of NPTX2 in ASPC1 cell line was methylated at 16 CpG sites. Contrarily these 16 CpG sites were not methylated in the whole blood DNA from the people without evidence of pancreatic disease.â‘£Using QMSP,we detected the MI of the whole blood DNA methylation of patients with pancreatic cancer is higher than that of people without evidence of pancreatic disease. The detection of methylation of fecal DNA had no significance between the three groups.Conclusion:We concluded that it was of great value to detect the methylation of NPTX2 gene for early diagnosis of pancreatic ductal adenocarcinoma.