送交者: Latino2 于 2006-3-02, 10:24:20:
十字花科蔬菜如青花菜含有一种Indole-3-carbinol（I3C)，和豆类中含有的异黄酮 (Genistein)可以刺激人体细胞产生修补DNA的蛋白质，从而减少基因突变以及癌症的发生。
这个理论假设早已有之， 但这回乔治城大学的研究人员首次从细胞和分子水平上显示了蔬菜预防癌症的作用。这个结果发表于本期”British Journal of Cancer“。
Veggies contain chemicals that boost DNA repair and protect against cancer
Need another reason to eat your vegetables? New research shows that some of them contain chemicals that appear to enhance DNA repair in cells, which could lead to protection against cancer development, say Georgetown University Medical Center researchers.
Dr. Rosen is available for interviews with the news media and may be contacted at the number above. For a copy of the study, go to http://www.nature.com/bjc or contact the Office of Communications at 202-687-5100.
In a study published in the British Journal of Cancer (published by the research journal Nature) the researchers show that in laboratory tests, a compound called indole-3-carinol (I3C), found in broccoli, cauliflower and cabbage, and a chemical called genistein, found in soy beans, can increase the levels of BRCA1 and BRCA2 proteins that repair damaged DNA.
Although the health benefits of eating your vegetables--especially cruciferous ones, such as broccoli--aren't particularly new, this study is one of the first to provide a molecular explanation as to how eating vegetables could cut a person's risk of developing cancer, an association that some population studies have found, says the study's senior author, Eliot M. Rosen, MD, PhD, professor of oncology, cell biology, and radiation medicine at Georgetown's Lombardi Comprehensive Cancer Center.
"It is now clear that the function of crucial cancer genes can be influenced by compounds in the things we eat," Rosen says. "Our findings suggest a clear molecular process that would explain the connection between diet and cancer prevention."
In this study, Rosen exposed breast and prostate cancer cells to increasing doses of 13C and genistein, and found that these chemicals boosted production of BRCA1, as well as its sister repair protein, BRCA2. Mutations in either of these genes can lead to development of breast, prostate and ovarian cancers.
Since decreased amounts of the BRCA proteins are seen in cancer cells, higher levels might prevent cancer from developing, Rosen says, adding that the ability of I3C and genistein to increase production of BRCA proteins could explain their protective effects.