High Fat-Diet, Excess Estrogens During Pregnancy May Result in Hereditary Breast Cancer

The eating habit of woman during pregnancy determines the health of future generations. Emphasizing this fact, researchers say excess estrogens exposure of the womb or high-fat diet induced epigenetic changes in pregnant woman can increase the risk of generations of breast cancer events.

Researchers from the Georgetown University conducted experiments on rats to find out the root cause of some hereditary breast cancers. They found excess estrogens and a high-fat diet during pregnancy negatively affecting the health of multiple generations and ultimately escalating their breast cancer risks.

 "We know that maternal diet can have long lasting effects on an offspring's health, but this study demonstrates, for the first time, that excess estrogens and a high-fat diet can affect multiple generations of a rat's offspring, resulting in an increase in breast cancer not only in their daughters, but granddaughters and great granddaughters," Leena Hilakivi-Clarke, a professor of oncology at Georgetown Lombardi Comprehensive Cancer Center, said in a statement from the University.

Hilakivi-Clarke and colleagues noted the quality of maternal diet affecting the fetal germ cells and a high-fat diet bringing in epigenetic changes in the breast tissue, and being passed on to following generations.

"This study could translate into important health implications," Sonia de Assis, the study's lead investigator, Georgetown Lombardi postdoctoral researcher, said. "Fatty foods are endemic in our society, and significant levels of substances that have hormonal activity similar to estrogens, called endocrine disrupting chemicals, have been found in food and drinking water."

To prove the link, investigators from Finland and the United States selected three groups of pregnant rats - one group provided with a high-fat diet, another with excess estrogen and the control group with a healthy diet.

The final results supported the researchers' theory.

"We found that if the mother was fed a high-fat diet before conception and throughout pregnancy, the increased breast cancer risk was transmitted to granddaughters through either male or female germ-line," de Assis explained.  The breast cancer risk in this group increased by 55 to 60 percent.

In the excess estrogen diet group, the results showed a 50 percent higher incidence of breast tumors in daughters, granddaughters and great-granddaughters.

After reaching a conclusion, the investigators also found the effectiveness of some medication in treating the occurrence.

"Our ongoing preclinical studies have found that the increase in breast cancer risk caused by in utero exposure to excess estrogens can be reversed by drugs that reverse epigenetic marks - chemical modifications that turns genes on and off - caused by the exposure," Hilakivi-Clarke said.

Findings of the study have been published in Nature Communications.

Breast cancer is one of the leading causes of cancer deaths among U.S. women. The latest estimate from the American Cancer Society says nearly 226,870 American women have invasive breast cancer and about 39,510 die from breast cancer every year.