The medical community has never really had a full understanding of endometriosis. The condition causes pain during intercourse as well as infertility and as many as 10 million American women are affected. Now, a researcher at Northwestern University's Feinberg School of Medicine has made some important discoveries about endometriosis.
Serdar Bulun, M.D., the George H. Gardner Professor of Clinical Gynecology at Northwestern, along with his colleagues, has been working on finding the causes of endometriosis for 15 years. Aside from finding important epigenetic abnormalities in endometriosis, he and his team determined that certain known chemicals can be used to treat the disease. Bulun's findings appear in the January 15, 2009 issue of the New England Journal of Medicine.
Of specific interest is the discovery of the presence of the enzyme known as aromatase in endometrial tissue. In healthy women, the endometrium serves as the lining of the uterus. In endometriosis this tissue is found outside of the uterus on other organs found in the pelvic area where this tissue copies the function of the endometrium. Aromatase is responsible for the production of estrogen, the female hormone.
In the healthy female, aromatase is not found in the endometrium. This finding means that women suffering from endometriosis have too much estrogen in the extra endometrial tissue found in such places as the ovaries, for instance. A protein called SF1 is responsible for the production of aromatase, and Bulun found that this protein, which is meant to cease its activity, remains active in women with endometriosis. As Bulun explains, "Estrogen is like fuel for fire in endometriosis. It triggers the endometriosis and makes it grow fast."
Due to these findings, Bulun began clinical trials with aromatase inhibitors, created to treat breast cancer, for women suffering from endometriosis. These drugs stop estrogen from forming and also help improve the body's ability to respond to progesterone. The result of this work is the current treatment favored for postmenopausal women who suffer from endometriosis. Bulun believes this can also be a good treatment for women in perimenopause who haven't responded to existing treatments for endometriosis.
Bulun also found that the progesterone receptor is shut down in women with endometriosis. Progesterone can benefit women with this condition because it can serve to stop endometrial growth. Without progesterone, the tissues remain in a state of inflammation and spread further afield.
Bulun's contention is that such defects occur during the early stages of an embryo's development and may be due to the mother's exposure to pollutants such as dioxin. It is hoped these new discoveries may lead to the prevention and treatment of the disease.