CHICAGO (Reuters) - The word has conjured fear and dread in the 13 million Americans diagnosed with it in the last decade: cancer. But will that always be so?
This week's news that the human genome is almost fully mapped has finally put cancer research on a whole new level, U.S researchers and doctors said.
``It's going to revolutionize the whole thing,'' Dr. Frederick Li, a world-famous cancer and genetics expert at Harvard University for whom a cancer syndrome is named, told Reuters.
According to the Merck Manual, cancer can develop at any time in any tissue or organ. It is uncontrolled cell growth with the ability to spread to other areas of the body.
With some notable exceptions, its ability to develop, grow and metastasize has regularly defied physicians' and researchers' attempts to stop it. About 550,000 Americans are expected to die of cancer this year, more than 1,500 per day. Some 1.2 million new cases will be discovered.
``There is absolutely no question that this is going to be a defining moment in both disease and health in general and in particular cancer,'' Dr. Ronald DePinho, one of the principal investigators at the Belfer Cancer Genomics Center at Dana-Farber Cancer Institute, said of the genome breakthrough.
``Cancer is the most complex genetic disorder that we face. Understanding the enemy, understanding the genetic underpinnings of a cancer cell, is the first step in developing rational therapeutic strategies.''
Dr. John Stevens, vice president for extramural grants at the American Cancer Society, was equally thrilled with the announcement that 97 percent of human genes have been mapped.
``This is going to change the way all of medicine is practiced and that, of course, relates naturally to cancer, and particularly so because cancer is a disease of the genes,'' he said. ``Will we ever get to a stage like polio or smallpox where we can totally eradicate cancer from the face of the Earth? I think it's a taller order than that, but we should significantly be able to reduce the burden by a huge amount. In a way, we are entering the era of genetic and molecular medicine.''
CANCER ONLY AN ASTROLOGICAL TERM?
President Clinton, at ceremony in Washington to mark the scientific landmark, said future generations may know the word cancer only in its reference to a constellation of stars.
``Genome science will have a real impact on all our lives,'' Clinton said, singling out breast cancer and leukemia as potential targets for highly specific drugs in the new era of cancer research.
Experts agreed the day may come when individuals, particularly those with family histories of a disease, will have their genetic profiles stored in a secure place, ready to be analyzed for mutated genes and thus altered gene products -- the proteins that direct the functions of our bodies.
``What I can envision is eventually what some of the multiple applications would be,'' Li said.
Those are better characterization of tumors leading to highly specific treatments and earlier diagnosis before symptoms appear, he said. ``There's also the possibility that if we understand how normal cells become cancer cells, we can use medications to prevent that transformation.''
Dr. Richard Schilsky, a clinician at the University of Chicago who treats cancer patients every day, is on the Food and Drug Administration board that approves new chemotherapeutic agents. Right now, he said, the only real commercial application of genetics in cancer is identification of the BRCA genes known to be involved in the development of hereditary breast tumors.
But more tests like that will follow as a result of the genome work, he said.
Better Early Detection Of Cancer
``I think that what we are all excited about is the potential to use the new genetic information in a variety of ways for better early detection of cancer, for better assessing the prognosis of patients, for improving the selection of therapy.''
Several experts pointed out that what was announced this week was simply the location of genes on the various human chromosomes, not their function or how they interact with each other. Much work lies ahead, they said.
Li noted that cancer is not just one disease but hundreds, perhaps many hundreds. ``In a cancer cell we don't know how many changes there are, there may be thousands,'' he said. ``How you dissect out and deal with all those changes'' is critical.
Researchers 15 or 20 years ago could not have conceived where genomics would be today, Schilsky said. Given this progress, he said, it is only a matter of time before the rest of the puzzle gets figured out.
``I think it's likely that the genes that are being identified here don't act individually, they probably act in concert with other genes. I would imagine within the next 10 years we're going to have a whole lot more information on that.''