Higher Sex Hormone Levels Raises Breast Cancer Risk

Women who naturally produce excess aromatase in their breasts have an increased risk of developing breast cancer, results of a new animal study suggests.

While current breast cancer therapies target both of those processes - inhibition of aromatase and inactivation of the estrogen receptor - the researchers say this study suggests that aromatase inhibitors may prove to be a more potent choice for cancer prevention in postmenopausal women.

"We know that estrogen is the fuel that most breast tumors use to grow, and this study shows us that making more estrogen in the breast, right next to cells that can use the hormone as fuel, appears to be a key trigger of early breast cancer," says the study's senior investigator, Priscilla Furth, M.D., professor of oncology and medicine at Georgetown Lombardi.

A lab study conducted by researchers at Georgetown Lombardi Comprehensive Cancer Center found that overproduction of aromatase, which converts testosterone into estrogen, in breast tissue is even more important in pushing breast cancer development than excess production of the estrogen receptor that the hormone uses to activate mammary cells.

What these results suggest for women is that if females vary in the amount of aromatase they naturally produce, as some studies suggest, then women with higher aromatase levels may be more susceptible to breast cancer, Furth says.

The study was recently published in the journal Cancer Research.

Source: ANI