If GERN could develop a drug that affected all cancers, they would clearly have a blockbuster drug. Financially, I think that rather than try to develop the drug themselves, they might do better to license the cloned enzyme to established drug makers for an up-front fee plus a percentage of sales. I would favor this approach since GERN probably does not have a library of compounds that they can screen as potential inhibitors. In addition, as far as I know they do not have the experience to successfully take a drug through clinical trials. For a new biotech company, this is often their greatest problem. They develop a compound that looks good in animals, and then try to rush it through clinical trials with consequent failure of both the drug and, ultimately, the company.
Another issue that I hadn't mentioned before is the problem of speed of killing for a telomerase inhibitor. If the inhibitor worked by simply blocking the action of telomerase, it probably would not be useful because a cell typically must undergo many divisions (>30) before telomere shortening results in cell death. If you are a cancer patient and have a tumor with a mass of 1 kg, the tumor would grow to a mass of about 1,000,000 kg before cell death would ensue. Alternatively, if you developed a drug that worked by "locking" the telomerase onto the DNA such that when the cancer cell tried to divide the cell would die because the telomerase locked onto the DNA screwed up replication, you would have a potentially useful drug (caveats include delivery, resistance and side effects). Since most normal cells lack telomerase, a potentially large advantage of highly specific telomerase inhibitors is minimal side effects. Sterility, probably temporary but potentially permanent, and killing of those stem cells that also have telomerase are the likely side effects. (If the drug is not highly specific, then other side effects can be expected.)
With respect to programmed cell death (AKA apoptosis), most cancer cells actually can still undergo apoptosis if treated in the appropriate manner. What they often lack is the ability to respond to signals that would normally cause them to die. Hence, anti-cancer drugs often induce apoptosis via pathways other than those that are faulty - for example, by blocking DNA replication. |
