Design of a Ribozyme to Inactive Telomerase Activity in Breast Cancer Tumors.

Telomerase expression has been associated with the immortality and metastasis of malignant breast cancer cells. Telomerase activity has been detected in several human cancers including breast, cervical and ovarian carcinomas. However, telomerase activity is either very low or not detectable in normal cells of the body. These observations suggest the development of anti-telomerase strategies may prevent cancer cell division without adverse effects on normal cell populations. This investigation describes the development of a novel therapeutic approach directed against the telomerase complex required for cancer cell division and metastasis. Catalytic RNA sequences, called ribozymes, will be expressed in breast cancer cell lines, to specifically recognize, cleave and eliminate the telomerase complex. This ribozyme therapy is designed to prevent tumor cell division and eliminate the metastatic potential of breast cancers. Retroviral vectors will deliver therapeutic genes encoding for the anti-telomerase ribozyme to breast cancer cells. These cells will be evaluated for anti-cancer ribozyme activity and for changes in cancer cell division to provide the basis for further development of this therapeutic approach in primary tumors from patients with malignant breast cancer. Gene therapy using ribozymes to eliminate cancer-causing molecules offers a promising strategy for the treatment of malignant breast cancer.