Estrogen Activities and the Cellular Effects of Natural Progesterone from Wild Yam Extract in MCF-7 Human Breast Cancer Cells

We studied the estrogenic activity and cellular effect of wild yam extract in MCF-7 human breast cancer cells. The extract increased the activity of the progesterone receptor and pS2 genes at the mRNA levels in human breast cancer MCF-7 cells, although the effects were not as prominent as those of 17 beta-estradiol (E-2). Western blot analysis showed that the level of estrogen receptor a protein was down-regulated after treatment with E2 or wild yam extract. Wild yam extract also inhibited proliferation of MCF-7 cells. These data indicate that wild yam extract acts as a weak phytoestrogen and protects against proliferation in human breast carcinoma MCF-7 cells.