Cancer
Garlic Inhibits DNA damaging chemical in breast cancer
By American Association for Cancer Research - News Release
Nov 1, 2005 - 9:56:00 AM

Changing Genes: Garlic Shown to Inhibit DNA Damaging Chemical in Breast Cancer

Legend suggests that garlic may ward off evil spirits, such as vampires. Now scientists are finding that garlic, or a flavor component of pungent herb, may help ward off carcinogens produced by meat cooked at high temperatures.

Cooking protein-rich foods like meats and eggs at high temperatures releases a chemical called PhIP, a suspected carcinogen. Epidemiological studies have shown that the incidence of breast cancer is higher among women who eat large quantities of meat, although fat and caloric intake and hormone exposure may contribute to this increased risk.

Diallyl sulfide (DAS), a flavor component of garlic, has been shown to inhibit the effects of PhIP that, when biologically active, can cause DNA damage or transform substances in the body into carcinogens.

Ronald D. Thomas, Ph.D., and a team of researchers at Florida A&M University in Tallahassee hypothesized that PhIP enhances the metabolism of the enzymes linked to carcinogenesis. They further suggested that the diallyl sulfide derived from garlic might counter this activity.

"We treated human breast epithelial cells with equal amounts of PhIP and DAS separately, and the two together, for periods ranging from three to 24 hours," said Thomas. "PhIP induced expression of the cancer-causing enzyme at every stage, up to 40-fold, while DAS completely inhibited the PhIP enzyme from becoming carcinogenic."

The finding demonstrates for the first time that DAS triggers a gene alteration in PhIP that may play a significant role in preventing cancer, notably breast cancer, induced by PhIP in well-done meats.

Thomas noted that no studies have shown a link between cooking vegetables and fruits and PhIP, regardless of the method used.

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Founded in 1907, the American Association for Cancer Research is a professional society of more than 24,000 laboratory, translational, and clinical scientists engaged in all areas of cancer research in the United States and in more than 60 other countries. AACR's mission is to accelerate the prevention and cure of cancer through research, education, communication, and advocacy. Its principal activities include the publication of five major peer-reviewed scientific journals: Cancer Research; Clinical Cancer Research; Molecular Cancer Therapeutics; Molecular Cancer Research; and Cancer Epidemiology, Biomarkers & Prevention. AACR's Annual Meetings attract nearly 16,000 participants who share new and significant discoveries in the cancer field. Specialty meetings, held throughout the year, focus on the latest developments in all areas of cancer research.

Contact: Elizabeth Tait
tait@aacr.org
215-440-9300
American Association for Cancer Research

Diallyl Sulfide Antagonizes PhIP Induced Alterations in the Expression of Phase I and Phase II Metabolizing Enzymes in Human Breast Epithelial Cells
Abstract # 2543, Ronald Thomas, Florida A&M University, Tallahassee.
Poster Session A. 5:30 p.m., Monday, October 31, 2005.