Quantitative analysis of NPTX2 hypermethylation in pancreatic cancer and its application in diagnosis of pancreatic cancer / 第二军医大学学报

ABSTRACT

Objective: To investigate the methylation level of NPTX2 gene in pancreatic cancer and assess its clinical value in diagnosis of pancreatic cancer. Methods: We detected the mRNA expression and methylation levels of NPTX2 gene by qRT-PCR and quantitative methylation with SYBR Green in 10 primary pancreatic carcinoma tissues and the matched adjacent normal tissues. The methylation levels of NPTX2 gene were then detected and compared using the above-mentioned method in the whole blood of patients with pancreatic ductal adenocarcinoma and healthy volunteers. Results: The relative quantification (RQ) of NPTX2 expression in pancreatic carcinoma tissues was significantly lower than that in the adjacent tissues (0.276±0.263 vs 3.526±3.037, P = 0.001). The result of quantitive methylation indicated that the methylation index (MI) of the carcinoma tissues was significantly higher than that of the adjacent tissues ([9.02±7.52]% vs [1.28±0.98]%, P = 0.003). MI of NPTX2 gene was negatively correlated with RQ value (R= -0.552, P = 0.012). We also found that the MI of the whole blood DNA methylation of patients with pancreatic cancer was significantly higher than that of healthy volunteers ([1.80±1.76]% vs [0.84±0.45]%, P < 0.05). Conclusion: Our findings strongly suggest that NPTX2 gene is aberrantly hypermethyated in pancreatic ductal adenocarcinoma. Detection of MI of NPTX2 gene might be of great value for diagnosis of pancreatic cancer.