Folic acid supplements, smoking and genetics are among research targets
MONDAY, April 20 (HealthDay News) -- Scientists looking at everyday factors that influence cancer risk are finding important new clues that could affect cancer prevention strategies.
"Many of us believe that prevention is better than trying to identify drugs for people after they get cancer," said Dr. Peter Shields, deputy director of the Lombardi Comprehensive Cancer Center and interim chairman of the Department of Medicine at Georgetown University Medical Center in Washington, D.C. "As we understand risk factors better, it may be possible to personalize cancer prevention."
Shields moderated a Monday teleconference highlighting cancer prevention-related findings that are being presented at the annual meeting of the American Society of Cancer Research, in Denver.
One study found that two common gene variants do not protect individuals from the ill effects of smoking.
In the study, smoking boosted the odds for the two most common types of colorectal polyps: adenomas and hyperplastic polyps, although the association was stronger in the latter.
People who had smoked a pack of cigarettes a day for a year had a 68 percent increased risk for adenomas but a 238 percent increased risk for hyperplastic polyps. Those still smoking had the same risk for adenomas as former smokers but a more than threefold increased risk for the second type of polyp.
Polyps can be precursors to colon cancer, but if they're detected early, the disease can often be prevented.
There was also a slight though not statistically significant risk from "charred" (well done) meat.
"Susceptibility to smoking did not vary by this gene, and everyone needs to be concerned [about the risk of smoking]," said Andrea N. Burnett-Hartman, a doctoral student at the Fred Hutchinson Cancer Research Center in Seattle.
"This gene is not going to protect you from the carcinogenic effects of smoking, at least in colorectal tissue," she said. In terms of meat consumption, she added that "everything in moderation" remains a good rule.
Another study found that specific genetic variations in the cox-1 and cox-2 genes indicate different risks for colorectal cancer. This might help determine who would benefit from the cancer-prevention benefits of nonsteroidal anti-inflammatory drugs (NSAIDs).
Although NSAIDs, including aspirin and cox-2 inhibitors, have been shown to reduce the risk of colorectal cancer, that benefit may be nullified by an increased risk of heart disease seen in some cox-2 inhibitors such as Vioxx, which was removed from the market.
Other findings being presented at the society's meeting include:
The American Cancer Society has more on preventing cancer.
SOURCES: April 20, 2009, teleconference with Peter Shields, M.D., deputy director, Lombardi Comprehensive Cancer Center and interim chairman, Department of Medicine, Georgetown University Medical Center, Washington, D.C.; Andrea N. Burnett-Hartman, doctoral student, Fred Hutchinson Cancer Research Center, Seattle; Neil Caporaso, M.D., section chief, U.S. National Cancer Institute; presentations, American Society of Cancer Research, annual meeting, Denver
All rights reserved