It is estimated that tens of thousands of breast cancer cases in the U.S. and Europe each year are attributable to alcohol consumption and that drinking is also associated with an increased risk of disease recurrence in women with early stage breast cancer.

The study objective was to determine how alcohol can affect the actions of estrogen in breast cancer cells. The research team not only established that alcohol increases estrogen-induced cell proliferation, but their findings also provide a direct link between alcohol, estrogen and a cancer-causing gene in promoting cancer cell growth.

They found that alcohol inappropriately promotes sustained expression of BRAF, even in the absence of estrogen, thereby mimicking or enhancing the effects of estrogen in increasing the risk of breast cancer.

Another key finding was that alcohol weakened Tamoxifen's ability to suppress the rapid growth of cancer cells. The authors think that their results suggest exposure to alcohol may affect a number of cancer-related pathways and mechanisms. They say these findings not only shed light on mechanistic actions of alcohol in breast cancer, but also provide fresh insight to the cross-talk between alcohol and cancer-related gene pathways and networks in breast cancer.

Their ultimate goal is to use this knowledge in breast cancer prevention, and their findings also have implications for women who are undergoing hormone replacement therapy for menopausal symptoms, as alcohol can affect the actions of the hormones they take to manage their symptoms.

The research highlights potential long-term health effects for college-age women, as well, who might find themselves in situations where heavy or binge drinking is part of the social environment.

http://www.uh.edu/news-events/stories/2016/March/031416LinAlcoholBreastCancer.php