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---------------------------------------------------------------------------- Cancer-related gene reportedly cloned ---------------------------------------------------------------------------- Copyright 1997 Nando.net Copyright 1997 N.Y. Times News Service (August 18, 1997 00:46 a.m. EDT) -- Geron Corp., a California biotechnology company, says it has cloned a gene believed to play a key role in cancer and age-related diseases, raising hopes about possible new treatments. In an article published in Friday's issue of the journal Science, researchers at Geron and the University of Colorado said they had successfully cloned the gene for the human telomerase catalytic protein, which is thought to play a key role in the regulation of cell life span, functioning as part of a molecular clock. The news, which came late last Thursday, caused the company's stock price to more than double the next day. Since the discovery of telomerase, its presence in tumor cells has raised hopes that it may offer a pre-eminent target for anti-cancer drugs. "The cloning of the active center of telomerase is a major milestone that sets the stage for more fully understanding the molecular genetics of aging and cancer," said Thomas Cech, a Nobel laureate and professor of biochemistry at the University of Colorado in Boulder, who collaborated with the Geron scientists. Geron's stock closed at $14 on Friday, up $7.50, with 12.5 million shares traded on Nasdaq. Analysts were struck by the size of the gain, on a day the market over all fell sharply. While the article's publication is significant for Geron, which has staked its future on the relevance of telomerase to cancer, such a scientific breakthrough is still many years removed from a potential drug, specialists said. Michael Sheffery, a securities analyst with Mehta & Isaly, said: "The cloning of the catalytic subunit of telomerase is the sine qua non for this company because this is the element that is a good pharmaceutical target. Having said that, this is a paper in Science. We're not talking about having a pharmaceutical, or even a lead. They have a target; now they have to start making bullets." Jim McCamant, editor of the Medical Technology Stock Letter, said investors should remember that the time between a scientific discovery and a potential drug is usually at least seven years, with many opportunities for failure along the way. The doubling of a biotechnology company's share price is rare, but "almost inevitably it's on a discovery, not something that will make you money," he said. Geron, which is based in Menlo Park, Calif., was founded four years ago to develop drugs for cancer and age-related diseases, and it soon focused on telomerase. In previous papers, scientists have shown telomerase to be active in many types of cancers but not in most normal tissues. Because telomerase is required for cancer cells to keep proliferating, Geron is seeking to discover anti-cancer drugs that will inhibit telomerase. Such a drug, the company hopes, would avoid the toxicity of chemotherapy. Conversely, in diseases of aging, activating telomerase could be beneficial by prompting the growth of new cells. "We are excited about moving this discovery into important new diagnostic and drug-discovery applications including telomerase as a product, because introduction of telomerase activity into mortal cells should extend their replicative life span," said Ronald Eastman, Geron's president and chief executive. Telomerase derives its name from telomeres, which are long chains of DNA at the ends of chromosomes, like genetic bookends. Telomeres appear to be a kind of cellular clock. With each division of a human cell, telomeres shrink, possibly offering the cell a measure of how many times it has divided, and how many more divisions remain until its innate life span is spent. Normal human cells divide 50 to 100 times. In cancerous cells, for reasons still not known, telomerase becomes activated, and the telomeres begin growing again. If telomere length is the cell's way of knowing when to die, and that length fails to diminish with each division, there may be no signal to block the runaway replication of malignancy. By LAWRENCE M. FISHER, New York Times <http://www.nando.net/newsroom/ntn/health/081897/health31_879_noframes.html> ---------------------------------------------------------------------------- [log in to unmask]