BOSTON -- Personal choices, such as smoking and consumption of fatty foods, have long been linked to increased cancer risk. During recent years, scientists have been seeking to isolate a variety of lifestyle decisions that may stave off the onset of cancer or even reduce tumor formation in their early stages. The latest round of such studies, presented at the American Association for Cancer Research's Frontiers in Cancer Prevention Research Meeting, include the impact of exercise on colon cancer in men, how aspirin consumption may negate the harmful effects of eating flame-broiled meat, and a new link between child bearing and lung cancer.
Effect of a 12-month exercise intervention on apoptosis in colon crypts: a randomized controlled trial
Exercising six days a week reduces the risk of colon cancer in men, according to a study by the Fred Hutchinson Cancer Research Center in Seattle. The study, conducted by Kristin Campbell, Ph.D., postdoctoral fellow, Public Health Sciences, and her colleagues, illustrated the role of exercise in controlling abnormal cell growth in colon tissue.
In men who engaged in moderate to vigorous exercise (an hour a day, six days a week) for a year, more apoptosis (normal cell life and death cycles) was seen in crypt cells in the colon. These cells are indentations in the colon wall and are the wellspring of polyps and other abnormal growths that can result in colon cancer. A protein called bax that promotes apoptosis was seen in higher amounts in the crypt cells among male exercisers. No such differences were seen in women, regardless of their exercise routines. But some changes in apoptosis were seen even among men who exercised less, about four times a week.
"We saw a substantial increase in the potential for cellular apoptosis in areas of the colon most vulnerable to colon cancer," said Campbell. "The increase was most pronounced in men who exercised six hours a week. No change was seen in
Contact: Warren Froelich
American Association for Cancer Research