Just last week, the government approved the first attempt to attack cancer at its molecular roots by inserting a tumor-destroying gene into a human patient's white blood cells. Doctors hope the "good" gene will counter the harm done by the "bad" gene that ran amok.
Thanks to extraordinary advances in molecular biology in the 1980s, researchers are exploring the underlying causes of cancer hidden in the nucleus of the cell.
"We live in a time when cancer research has achieved an astonishing level of excitement and importance," said Dr. Samuel Broder, director of the National Cancer Institute (NCI) and commander-in-chief of the federal government's assault on cancer.
"Gene therapy, which only a decade ago was a theoretical concept, is now a reality at the experimental level," Broder noted in the NCI's latest progress report.
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The 1982 identification of a cancer-causing gene called "ras" - and the subsequent discovery of about five dozen others - has opened new doors to understanding, detecting, preventing and possibly curing the disease.
Scientists now can dig inside a cancerous tumor in a lung, breast or other organ, deep inside a malignant cell, all the way down to a minute fraction of a single molecule - to see how cancer is born, spreads and kills.
Their new insights show that cancer is, at bottom, a genetic disease, since genes control growth, and cancer is, by definition, uncontrolled growth.
Researchers have learned that some genes accelerate growth, like the gas pedal in a car. Others suppress growth, like a brake. A failure by either, or both, can lead to cancer.
If a cancer gene is located in the reproductive cells, it is inherited and may be passed on to children and grandchildren. Many malignancies run in
families; for example, about a third of all Americans inherit a gene that predisposes them to cancer of the colon, though by no means all of them will get it.
