Common Antioxidant May Decrease Risk of Breast Cancer

 

 

Behind the Cancer Headlines®

July 15, 2003

 

 

Researchers believe that higher total cysteine levels may be associated with a lower risk of breast cancer, according to a study presented at the annual meeting of the American Association for Cancer Research.

 

Cysteine, an amino acid, is the precursor to glutathione (a powerful antioxidant and important detoxifying agent). Glutathione is used to cleanse the body of harmful toxins. N-acetylcysteine, a synthetic precursor of cysteine, is commonly used as a mucolytic agent and as an antidote against acetaminophen-induced hepatotoxicity.

 

Women in the highest level of plasma cysteine group had a significant 56 percent reduction in risk of developing breast cancer as compared with those in the lowest level group. The association was not significantly altered by any other major risk factors related to breast cancer, except that a stronger association was observed among leaner women.

 

"The findings suggest that higher levels of total cysteine may predict a reduced risk for breast cancer," said Dr. Shumin Zhang, of Brigham and Women's Hospital, Harvard Medical School, and Harvard School of Public Health, and lead investigator on the study. "Based on these results, we are hopeful that cysteine or its precursors may have potential chemopreventive benefits against breast cancer."

 

The prospective, case-controlled study was conducted among 32,826 women in the Nurses' Health Study. A total of 712 incidents of breast cancer were matched to 712 controls by year of birth, time of day that the blood was drawn, fasting status, month of blood sampling, recent use of postmenopausal hormones at the time of blood collection, and menopausal status. Scientists used conditional logistic regression with adjustment for other breast cancer risk factors to estimate the relative risks for breast cancer by levels of plasma total cysteine.

 

The Nurses' Health Study was initiated in 1976 at Brigham and Women's Hospital. The NHS is the longest running major women's health study ever undertaken and has resulted in hundreds of journal articles, many containing groundbreaking findings on how to prevent some of the major causes of disease and death in women.

 

 

SOURCE:

 

Annual Meeting of the American Association for Cancer Research, July 14, 2003, Washington, DC