Gastric cancer with high telomerase activity shows rapid development and invasiveness

Telomerase activity was reported to be activated in most immortal cells and cancers. As the clinical significance of telomerase activity in human gast ric cancer is controversial, we investigated this activity using a telomeri c repeal amplification protocol. The telomerase activity was tentatively de fined by strength of activity as follows: 3+, observed with 0.06 mug of pro tein; 2+, observed with 0.6 mug of protein; 1+, observed with 6 mug of prot ein; 0, not observed under these three conditions. Telomerase activity was detected in 35 of 39 (89.7%) gastric cancer specimens. Tumors with high tel omerase activities (2+/3+) tended to have a deeper invasion, lymphatic and vascular invasion, lymph node metastasis, liver metastasis, and peritoneal dissemination, as compared to findings in case of low telomerase activities (-/1+). Thus, telomerase activity of gastric cancer tissue may reflect the malignant potential of the tumor and intensive postoperative care might be required for such patients.