Drinking alcohol may increase breast cancer risk: study

Drinking alcohol can put you at increased risk of breast cancer by enhancing the levels of a cancer-causing gene, a new study has warned.
"Our research shows alcohol enhances the actions of estrogen in driving the growth of breast cancer cells and diminishes the effects of the cancer drug Tamoxifen on blocking estrogen by increasing the levels of a cancer-causing gene called BRAF," said Chin-Yo Lin from University of Houston in the US.
Researchers 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 results suggest exposure to alcohol may affect a number of cancer-related pathways and mechanisms, researchers said.

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, they said.

The ultimate goal is to use this knowledge in breast cancer prevention, but the 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, Lin said.
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.
"We hope these and future findings will provide information and motivation to promote healthy behavioural choices, as well as potential targets for chemoprevention strategies to ultimately decrease breast cancer incidents and deaths within the next decade," said Lin.

The findings were published in the journal PLOS ONE.