Possibility of Drug Treatment to Prevent Breast Cancer
1 Jan, 2007 04:26 pm
Over 200,000 women will be diagnosed with breast cancer this year, but thanks to new findings, at least five percent of those cases can potentially be prevented in the future, not by mastectomies or ovariectomies as is the current practice, but by taking medication. Anxious women shouldn?t get their hopes up quite just yet, but studies have shown that drugs touting the ability to block certain sex hormones, such as the abortion drug RU-486, might be able to prevent the formation of hereditary breast cancer.
It’s unclear as of yet how the gene is able to normally suppress carcinogenesis in the breast and the ovaries, but a recent study published in Science by the Eva Lee lab at the University of California, Irvine was able to demonstrate that mice deficient in the BRCA1 and the tumor-suppressor gene p53 underwent the kind of extreme mammary duct formation only found during pregnancy. Further studies showed that the mutant mammary epithelial cells over-expressed progesterone receptors, making them more susceptible to the effects of progesterone, which induces the growth of mammary ducts. However, the mice that were treated with RU-486 not only lacked those effects—they were also tumor free after one year, compared to the untreated mice, which developed tumors by eight months.
The same experiment was carried out to determine the effects of estrogen on the mutant mice, but it doesn’t appear as though estrogen receptors are expressed any more in genetically deficient mice than their healthy brethren. While the cancer prevention studies have only been carried out in mice, it delivers interesting implications about the human breast cancer, and opens up many new avenues of research.
No one is suggesting that RU-486 be used to prevent breast cancer, but the findings do shed an important light on the possibility of using anti-progesterone treatments in the future to prevent hereditary breast cancer. A lot of work remains to be done before the problem is fully solved, but the scientific community is already one step closer.
Poole, A.J., Li, Y., Kim, Y., Lin, S.-C., J., Lee, W.H., Lee, E. Y.-H.P. Science 1 December 2006: Vol. 314. no. 5804, pp. 1467 – 1470 DOI: 10.1126/science.1130471