Telomerase as a new target for pancreatic cancer treatment.

Over the past several years, tremendous efforts have been made to understand the role of telomerase in the development and progression of human cancers. It has become clear that: (1) telomerase activity has been found in a majority of human cancers, whereas most benign diseases and normal tissues do not express this enzyme; (2) telomerase prevents cells from undergoing replicative senescence and contributes to their unlimited proliferation; (3) telomerase can protect cells from DNA damage and subsequent apoptosis; and (4) telomerase activity may correlate with the aggressive behavior (e.g., migration and invasion) of tumor cells. Based on these findings, telomerase has been proposed as a potential target not only for cancer diagnosis but also for anticancer therapies. A growing number of telomerase inhibitors have been developed and, in some cases, have been shown to suppress the growth of tumor cells in vitro and in vivo. On the other hand, several issues still need to be addressed before these drugs are moved into clinical trials. This review focuses on the recent progress in telomerase research and its implications in pancreatic cancer treatment.