Imetelstat Shows Potential for Prostate, Brain Cancer
Telomerase inhibitor may reduce prostate tumor-initiating cells; also crosses blood-brain barrier
FRIDAY, Jan. 8 (HealthDay News) -- The telomerase inhibitor imetelstat may be useful in treating glioblastoma and prostate cancer, according to research published online Jan. 4 in Clinical Cancer Research and online Nov. 11 in the International Journal of Cancer.
In one study, Calin O. Marian, Ph.D., of the University of Texas Southwestern Medical Center in Dallas, and colleagues analyzed data from in vitro and animal experiments. Imetelstat was found to dose-dependently inhibit telomerase activity of glioblastoma tumor-initiating cells. Long-term treatment was associated with telomere shortening, decreased proliferation, and cell death in these cells. The drug penetrated the blood-brain barrier sufficiently to block most telomerase activity in human glioblastoma orthotopic xenograft cells in mice. In addition, imetelstat treatment led to a decrease in the subcutaneous tumor growth rate in mice.
In the other study, Marian and colleagues write that targeting prostate cancer tumor-initiating cells may be the only way to eliminate these tumors. They found that imetelstat inhibits telomerase activity in such cells, and long-term treatment may decrease the number of tumor-initiating cells and inhibit self-renewal in prostate cancer cell lines.
"In summary, this preclinical study shows that telomerase inhibition has a great potential for the treatment of prostate cancer and may be able to target the tumor-initiating cells that contribute to relapse and metastasis," the authors conclude.
Geron Corporation provided imetelstat for the studies. Two co-authors reported financial relationships with Southland Financial Corporation.