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Researchers such as Dr. David Sidransky, an oncologist at Johns Hopkins University, are searching for diagnostics that will pick up other cancers in their preliminary stages. Others are focusing on an even earlier stage, trying to lower the risk of developing cancer to begin with. Here the most exciting work centers on the cycooxygenase inhibitor called COX-2. This pain reliever was originally developed to clamp down on inflammation as aspirin does but without aspirin's tendency to eat through the lining of the stomach.
It turns out that COX-2 inhibitor drugs also have anticancer effects, reducing the number of precancerous polyps in patients with a hereditary form of colon cancer, perhaps through antiangiogenesis. Scientists are currently studying its effect on noninherited colon cancers. And because the receptor for COX-2 is overexpressed on a range of human cancer types, the hope is that COX-2 inhibitors may be useful in preventing a wider range of cancers, including head and neck, bladder, non-small cell lung and breast cancers.
As promising as these therapies are, there remain many questions for researchers to answer. Among the most important: Which treatments should be given to which patients? Says Sidransky: "Within five years, it might be almost impossible to bring a drug forward without having a test to help doctors decide whom the drug is for."
Eventually, the goal is to detect precisely which molecular processes have gone wrong in an individual patient's cancer. Rather than being identified as lung cancer or breast cancer or kidney cancer, tumors will be tagged as EGFR positive, for example, or COX-2 positive. "The dream," says M.D. Anderson's Mendelsohn, "is that if Mrs. Smith gets a breast biopsy, we'll be able to say, 'Here are the four genes that are abnormal in her tumor,' pull open a drawer, pick out the antibodies or small molecules designed against the abnormal products of those genes, and give her a cocktail targeting the genes that caused her cancer."
That dream comes at a price. Staying on Gleevec, for example, may end up costing patients like Victoria Reiter as much as $2,400 every month--nearly $30,000 a year--for the rest of her newly prolonged life. While the National Cancer Institute funds basic research into cancer biology, the bulk of drug development is done by for-profit pharmaceutical firms. These companies claim that it costs them between $500 million and $1 billion to bring a single new medicine to market--partly because it can take 15 years for the exhaustive testing in animals and humans required by U.S. law and partly because for every medicine finally approved by the FDA, 5,000 others fail somewhere along the way. The drug companies count on that one success to pay for the 5,000 failures. Meanwhile, pharmaceutical firms are under attack both for allegedly conspiring to keep cut-rate competitors out of the market and for profiting handsomely from basic research that was originally funded by the taxpayers.