SCIENTISTS LEARNING WHY CERTAIN FOODS STAVE OFF CANCER

                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: TUESDAY, April 13, 1993                   TAG: 9304130219
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A1   EDITION: METRO 
SOURCE: The New York Times
DATELINE:                                 LENGTH: Medium
SCIENTISTS LEARNING WHY CERTAIN FOODS STAVE OFF CANCER
Cached away in the soul of every red-blooded American who fondly recalls when carnivory was a virtue, and supper wasn't supper without a centerpiece of pork chops or prime rib, lies the frail hope that all the recent emphasis on fruits, grains and vegetables will somehow turn out to be a terrible mistake.
Well, the time has come to release that hope and give it a proper burial at last. The truth is that the more researchers understand about the ingredients found in fruits, vegetables, beans and herbs, the more impressed they are with the power of those compounds to retard the bodily breakdown that results in cancer and other chronic diseases.
Nutritionists and epidemiologists have long observed that people who eat a plant-rich diet suffer lower rates of cancer than do meat loyalists, and now scientists are beginning to figure out why.
Beyond the well-known benefits of vitamins and fiber, plant foods are plush with chemicals that have no nutritional value and are not necessary for immediate survival yet may impede cancer at a variety of stages in its slow, savage evolution.
Most of the experiments performed so far have been done on animals or isolated cells, and no specific ingredient from fruits or vegetables has been proved in long-term human trials to prevent or retard cancer. But biologists are encouraged that many laboratory results are in harmony with the empirical studies of long-lived populations.
And just when researchers thought they had a reasonable grasp of the basic anti-cancer compounds that might be found in a healthy diet, they discover a novel pathway through which ingredients in plants may help foil disease.
In the current issue of The Proceedings of the National Academy of Sciences, scientists from Children's University Hospital in Heidelberg, Germany, report that they have isolated a compound called genistein from the urine of people who eat a traditional Japanese diet, heavy on soybeans and vegetables. Through test-tube experiments with a synthetic version of the chemical, Dr. Lothar Schweigerer, his student Theodore Fotsis and their colleagues, have discovered that genistein blocks an event called angiogenesis, the growth of new blood vessels.
That could have significant implications for both the prevention and treatment of many types of solid tumors, including malignancies of the breast, prostate and brain. Scientists had previously determined that if a tumor was to expand beyond a millimeter or two in size, or four-hundredths to eight-hundredths of an inch, it first must foster the growth of new capillaries around it. Once it is fully vascularized, the malignancy then receives the oxygen and nourishment it needs to keep swelling, eventually invading the blood and lymph system and seeding fatal metastatic colonies elsewhere in the body.
By inhibiting capillary growth, genistein just may keep new tumors from growing beyond harmless dimensions.

by Bhavesh Jinadra by CNB