Why Obese Women Are Prone To Developing Breast Cancer

Scientists at the University of Illinois have discovered that free fatty acids in the blood cells promote the spread and growth of breast cancer cells. This discovery could help explain the reason why obese women are prone to developing breast cancer after menopause.

Professor Zeynep Madak-Erdogan, a food and nutrition scientist who led the study in a statement said, "when taken up by estrogen-receptor positive breast cancer cells, these fatty acids activate pathways that increases tumor cell growth, survival and proliferation."

However, in order to determine the impact that obesity has on ER-positive cancer cells, the researchers treated different types of primary tumor and metastatic cancer cells with the blood of obese women. They then discovered that the cancer cells became more viable and multiplied.

According to the study, the fatty acids in the women's blood increases the risk of the disease. One line of primary tumor cells became more motile and an enzyme pathway that regulate cell growth, proliferation and survival in a metastatic cell line was activated.

Again, the higher the cells' level of exposure to the fatty acids, the more pronounced the effect on the enzyme pathway known as mammalian target of rapamycin or mTOR pathway.

Besides, in order to examine how estrogen would affect gene expression in the recent study, they treated one group of breast cancer cells with oleic acid - a fatty acid - and another group of cells with a combination of oleic acid and estrogen.

The oleic acid increased the expression of genes involved in cell proliferation and reduced down about 500 genes, including those involved in fatty acid metabolism and adhesion with other cells. The research team found that these effects were greatly reduced in cells that were treated with estrogen and oleic acid combination, and concluded that fatty acids in cells promote breast cancer.