| 摘要 |
Natural progesterone inhibits the proliferation of normal breast epithelial cells in vivo, as well as breast cancer cells in vitro. The anti-proliferative activity of natural progesterone in normal tissue is due to its ability to induce apoptosis. The genes P53 and bcl-2 genetically control the apoptic process and are involved in the natural progesterone induced apoptosis. Natural progesterone levels similar to levels seen during the third trimester of pregnancy exhibited a strong anti-proliferative effect on at least two breast cancer cell lines. Apoptosis was induced in the stronger progesterone receptor expressing T47-D cells. Exposure of T47-D breast cancer cells to natural progesterone significantly down regulated expression of bcl-2 and concomitantly up-regulated expression of p53, indicating both genes are involved in natural progestorone-induced apoptosis. A composition containing exogenous natural progesterone formulated for topical application is disclosed which may be used to establish and maintain a plasma concentration of natural progesterone of greater than 10 nanograms per ml which level is sufficient to destroy breast cancer cells. |
