Telomerase inhibitors.

Telomerase is attracting great interest as a target for anticancer research because telomerase activity is present in most malignant cells, but undetectable in most normal somatic cells. The antisense approach has been widely exploited and directed to telomerase RNA, chiefly the template region. Ribozymes have been less investigated. Agents that stabilize folded G-quadruplex structures also inhibit telomerase. Inhibitory agents from many chemical classes have been identified, many through screening, but their specificity of action is in doubt. A specific inhibitor is expected to immediately inhibit activity but not cell division, produce telomerase shortening over multiple generations, and ultimately produce end-to-end chromosomal fusion and growth arrest.