Mechanism-based combination telomerase inhibition therapy

Inhibition of telomerase is an exciting therapeutic target, since it is required for the long-term proliferation of most cancer cells but not present in most somatic cells. However, effective telomerase inhibitors have yet to be tested in clinical trials. In this issue of Cancer Cell, Seimiya and coworkers (Seimiya et al., 2005) explore inhibiting tankyrase, an enzyme involved in making telomeres accessible to telomerase. Adding a partial inhibition of tankyrase to a partial inhibition of telomerase drove cancer cells into crisis and death. The combination of tankyrase and telomerase inhibitors may offer new opportunities for realizing the promise of telomerase inhibition therapy.