X-Message-Number: 18600 Subject: SF Gate: Researchers optimistic on cancer drugs/Could treat rarer forms of disease From: "Peter Christiansen" <> Date: Tue, 19 Feb 2002 14:37 -0800 FYI ---------------------------------------------------------------------- This article was sent to you by someone who found it on SF Gate. The original article can be found on SFGate.com here: http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2002/02/19/MN62513.DTL ---------------------------------------------------------------------- Tuesday, February 19, 2002 (SF Chronicle) Researchers optimistic on cancer drugs/Could treat rarer forms of disease Sabin Russell, Chronicle Staff Writer Boston -- Equipped with the map of the human genome, cancer researchers are hoping to replicate on a larger scale the startling successes specialized drugs have achieved on rarer forms of the disease. At the 168th national meeting of the American Association for the Advancement of Science, a panel of top cancer researchers outlined new strategies against one of the world's most complex and fearsome killers. "If there are going to be any 'wins' in the future, they will come incrementally," with greater understanding of the underlying molecular biology of cancers, said Dr. David Livingston, deputy director of the Dana-Farber Cancer Institute at Harvard. Last year's highly publicized achievement of mapping the human genome -- identifying most of the 30,000 genes that contain instructions for creating and maintaining human cells -- has opened a treasure trove of information that molecular biologists have only begun to explore. Among the surprises was the discovery of genes for more than 500 "protein kinases," which are molecules that act as switches that turn chemical processes on or off. When one of those switches mutates, it can mean big trouble. It was the discovery of one such misbehaving kinase -- and the creation of a drug that blocks it -- that is creating such excitement among cancer researchers as they consider hundreds of other potential targets. Last year, the Food and Drug Administration granted pharmaceutical giant Novartis accelerated approval of a drug called Gleevec, which was specifically designed to block the action of this misbehaving kinase. Normally, this chemical switch turns on the manufacture of certain white blood cells. In the mutated form, it is stuck in the "on" position, causing a deadly disease called chronic myeloid leukemia. Gleevec was designed to slip onto a saddle-like ridge on the surface of the faulty molecule, blocking its ability to overproduce white blood cells. In clinical trials, 53 out of 54 patients had normal blood counts restored -- an unprecedentedly powerful response against a cancer. Since then, the same drug was found also to block action of another mutated kinase that causes a rare abdominal tumor, called gastrointestinal stromal cancer. The FDA approved Gleevec to treat that disease Feb. 1. Livingston, whose work is partially supported by Novartis, speculates that "other mutated, uncontrolled kinases" may be linked to lymphoma and cancers of the breast, prostate and lung, which make up 90 percent of cancer cases. By developing screens that compare the genes inside a tumor sample to the human genome's library of properly behaving kinases, researchers might be able to isolate more faulty ones, Livingston said. Another highly promising target for researchers is the process by which cancer cells "recruit" blood vessels to grow around them, a key step in making genetically damaged cells sprout into dangerous tumors. Dr. Judah Folkman, of Harvard's Boston Children's Hospital, told the audience that 24 drugs targeting this process, known as angiogenesis, were in clinical trials. The same phenomenon is implicated in noncancerous diseases, such as macular degeneration, which causes blindness in millions of elderly people, he noted. The blood vessel growth process may also be involved in endometriosis, a painful gynecological disease where tissue from the uterus migrates and grows in other parts of the body. Folkman called angiogenesis activity a "unifying principle" found in different diseases. "If you drain the Pacific Ocean," he said, "you should not be surprised to find that islands are all connected." ---------------------------------------------------------------------- Copyright 2002 SF Chronicle Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=18600