Researchers at the University of Houston have discovered a cancer-causing gene triggered by alcohol. And now, a new study has been completed to determine how alcohol consumption might affect the actions of estrogen in breast cancer cells.

During this research, scientists not only discovered that alcohol increases estrogen-induced cell proliferation, but that it also provides a direct link between alcohol, estrogen and a cancer-causing gene in promoting cancer cell growth.

"Alcohol consumption is prevalent among women in the U.S. and is a risk factor for breast cancer," UH cancer biologist Chin-Yo Lin, said. "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."

Statistics show that there are tens of thousands of breast cancer cases in the United States and Europe each year that are attributable to alcohol consumption. Furthermore, researchers believe that drinking may increase the risk of disease recurrence in women with early stage breast cancer.

Findings showed that consumption of alcohol promotes sustained expression of BRAF (mutations found in a wide range of cancers) despite the absence of estrogen, which results in the enhancement of the effects of estrogen and increases the risk of breast cancer. Alcohol also weakened the commonly used breast cancer drug Tamoxifen's ability to suppress the rapid growth of cancer cells.

Researchers said they are hopeful that their findings may help prevent breast cancer. The findings also hold important implications for women who are undergoing hormone replacement therapy for menopausal symptoms since alcohol can disrupt the actions of the hormones taken to manage symptoms.

"We hope these and future findings will provide information and motivation to promote healthy behavioral choices, as well as potential targets for chemoprevention strategies to ultimately decrease breast cancer incidents and deaths within the next decade," Lin said. "We want to provide women, in general, with more information and insight to be better able to balance their consumption of alcoholic beverages with the potential health risks, including cancer patients who may want to take into consideration the potential detrimental effects alcohol consumption might have on treatments and modify their behavior and habits accordingly."

The paper, titled "Alcohol Regulates Genes that Are Associated with Response to Endocrine Therapy and Attenuates the Actions of Tamoxifen in Breast Cancer Cells," was published in the journal Proceedings of the National Academy of Sciences (PNAS).