In continuation of my update on Telomerase inhibitors, I find this info really interesting and hence sharing here with. As mentioned in my earlier blog about imetelstat (GRN163L ) has been undergoing Phase I clinical trials designed to examine the safety, tolerability, pharmacokinetics and pharmacodynamics of the drug, alone or in combination, in solid tumors, chronic lymphoproliferative disease, multiple myeloma, lung and breast cancers and the company claims that Phase I objectives for imetelstat (structure) have been achieved. Now Dr. Jerry Shay, professor of cell biology of The University of Texas Southwestern Medical Center at Dallas, claims that the same drug shows promise in fighting the brain cancer glioblastoma and prostate cancer.
Glioblastomas are the most common malignant brain tumors in adults, according to the American Cancer Society. They are difficult to treat with drugs because blood vessels in the brain have tightly constructed walls that allow only a few substances to pass through.
The researcher focused on cells called tumor-initiating cells. Some researchers believe that tumors contain a small subset of initiating cells – or cancer stem cells – that are able to initiate and drive tumors and that are often resistant to radiation therapy and chemotherapy.
In the glioblastoma study, Dr. Shay and his colleagues found that imetelstat blocked the action of telomerase in isolated tumor-initiating cells as well as the bulk of the tumor cells, eventually killing the cells. Combining imetelstat with radiation and a standard chemotherapy drug made imetelstat even more effective. When the researchers implanted human tumor-initiating cells into rodents, they found that imetelstat was able to enter brain tissue and inhibit telomerase activity.
In the prostate cancer study, the researchers isolated tumor-initiating cells from human prostate cancer cells. The cells showed significant telomerase activity. Imetelstat blocked the enzyme’s activity, and telomeres shortened greatly. As per Dr.Shay, since the drug attacks a mechanism that is active in most cancers, it might prove to be widely useful, especially when combined with other therapies.
The researcher focused on cells called tumor-initiating cells. Some researchers believe that tumors contain a small subset of initiating cells – or cancer stem cells – that are able to initiate and drive tumors and that are often resistant to radiation therapy and chemotherapy.
In the glioblastoma study, Dr. Shay and his colleagues found that imetelstat blocked the action of telomerase in isolated tumor-initiating cells as well as the bulk of the tumor cells, eventually killing the cells. Combining imetelstat with radiation and a standard chemotherapy drug made imetelstat even more effective. When the researchers implanted human tumor-initiating cells into rodents, they found that imetelstat was able to enter brain tissue and inhibit telomerase activity.
In the prostate cancer study, the researchers isolated tumor-initiating cells from human prostate cancer cells. The cells showed significant telomerase activity. Imetelstat blocked the enzyme’s activity, and telomeres shortened greatly. As per Dr.Shay, since the drug attacks a mechanism that is active in most cancers, it might prove to be widely useful, especially when combined with other therapies.
Hope Geron people must be really happy for these results and conclusions.....
Ref : http://www.utsouthwestern.edu/utsw/cda/dept353744/files/570509.html
