WASHINGTON, DC Researchers from Georgetown Lombardi Comprehensive Cancer Center demonstrate, in animals, that maternal exposure to a high-fat diet or excess estrogen during pregnancy can increase breast cancer risk in multiple generations of female offspring daughters, granddaughters and even great-granddaughters.
This study, published online today in Nature Communications, shows for the first time that the risk of some "familial" breast cancers originate from biological alterations caused by maternal diet during pregnancy that not only affect the directly exposed fetus but also the fetal germ cells, transmitting the increased mammary cancer risk to subsequent generations.
This study also provides some hints about the biological mechanisms behind this multi-generational transmission of risk. The researchers found that maternal intake of high-fat diets and excess estrogens changes DNA methylation patterns in the offspring's breast and make it more sensitive to carcinogens later in life. Importantly, these traits are inheritable.
"We know that maternal diet can have long lasting effects on an offspring's health, but this study demonstrates, for the first time, that a high fat diet or excess estrogen 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," says the study's senior investigator, Leena Hilakivi-Clarke, Ph.D., a professor of oncology at Georgetown Lombardi.
The research team, which includes investigators from institutions in Finland and the United States, tested three groups of pregnant rats and their progeny. The two exposed groups of rats were at heightened risk for developing breast cancer, compared to the control group.
In the first group, rats were fed a high fat diet before conception and throughout pregnancy. Breast cancer risk was increased by 55 to 60 percent in the daughters and granddaughters of r
|Contact: Karen Mallet|
Georgetown University Medical Center