Molecular diagnosis of pancreatic cancer by telomerase

点击翻译按钮获取中文摘要

To assess the clinical significance of telomerase on the diagnosis and the treatment of pancreatic cancer, telomerase activity was evaluated using telomeric repeat amplification protocol in surgically resected pancreatic tissues and in pancreatic juice.When the cutoff value was set at 1.00, the positivity rate of telomerase activity in pancreatic cancer tissues was 96.1%, whereas all tissues of adenoma, pancreatitis, normal pancreas and normal pancreatic ducts were negative. We also measured telomerase activity in pancreatic juiced obtained from the patients with pancreatic disorders through balloon catheter inserted into the pancreatic duct with an i.v. injection of secretin. The positive rate of telomerase activity was 83.3% in pancreatic juice from carcinoma patients, whereas only 4.3% was positive in that from adenoma patients. All of pancreatic juice from pancreatitis patients were negative in telomerase activity. The results indicate that measurement of telomerase activity in pancreatic juice may serve as a useful diagnostic tool for the pancreatic cancer.Since telomerase is specifically activated in pancreatic cancer, telomerase could be a target for the treatment of pancreatic cancer. Telomerase activity was inhibited by the transduction of wild type p53 using recombinant adenovirus, followed by significant apoptosis. 9-Hyroxyellipticine specifically inhibited telomerase activity of pancreatic cancer cells. Meanwhile, the exposure of VP-16 increased telomerase activity. The degree of telomerase activation inversely correlated with the induction of apoptosis. These results suggest that telomerase may have an anti-apoptotic role.