Progesterone Mimic Shows Promise in Breast Cancer Fight

Breast cancer is a tough opponent, but scientists might have found a new ally in the fight against it. A recent study suggests that a drug mimicking progesterone could help slow down tumor growth in women with hormone-sensitive breast cancer. The drug, called megestrol, is a synthetic version of progesterone. Researchers found that when women took megestrol alongside standard anti-estrogen therapy, their tumors grew more slowly. This was observed over a two-week period before surgery. Megestrol is already used to help manage hot flashes caused by hormone therapy. The study involved 198 women with ER-positive breast cancer, which means their tumors feed on estrogen. These women were given letrozole, a hormone therapy drug, along with either a low or high dose of megestrol, or no megestrol at all.The results were promising. Both doses of megestrol enhanced the effect of letrozole in slowing tumor growth. This is great news because lower doses mean fewer side effects. High doses of progesterone can cause weight gain and high blood pressure, so a lower dose could be a safer option. Lab tests on mice showed that progesterone works by indirectly blocking estrogen receptors in cancer cells, preventing them from dividing. However, more research is needed to see if these benefits last beyond two weeks. Hormone therapy is often preferred over chemotherapy because it's gentler and has fewer side effects. But even mild side effects can be tough to deal with over the long term. This study offers hope for improving the quality of life for women undergoing hormone therapy.