Submitted to: Food and Chemical Toxicology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/22/2002
Publication Date: 10/15/2002
Citation: ROWLANDS, M., BERHOW, M.A., BADGER, T.M. ESTROGENIC AND ANTIPROLIFERATIVE PROPERTIES OF SOY SAPOGENOLS IN HUMAN BREAST CANCER CELLS IN VITRO. FOOD AND CHEMICAL TOXICOLOGY. 2002. v. 40. p. 1767-1774. Interpretive Summary: There are several compounds bound to soy protein called phytochemicals. Many of these have been found to have biological actions. Therefore, when eaten as part of a soy-containing meal, these compounds become dietary factors that could alter the function of cells within the body. We have been interested in determining the function of the phytochemicals. We studied one class of soy phytochemical, the sapogenols in breast cancer cells that either contain estrogen receptors (MCF-7 cells) or that do not have the estrogen receptor (MDA cells). We found that one class of sapogenols (SA) acts like estrogens is some ways and stimulates growth of these cancer cells, while another class of sapogenols (SB) acts in an opposite manner to inhibit growth of these cancer cells. Further research is needed to determine if these soy compounds are absorbed and if they are capable of preventing cancers such as mammary or colon cancer.
Technical Abstract: Two soy sapogenols, soyasapogenol A (SA)and soyasapogenal B (SB) were tested for their estrogenic activities in estrogen responsive MCF-7 or estrogen-insensitive MDA-MB-231 (MDA) human breast cancer cells. SB and SA had differential actives on cell proliferation with 10 um SB being growth inhibitory to MDA cells with no significant effect at any concentration on MCF-7 cells. SA also inhibited MDA cell proliferation at 10um, but at this same dose stimulated a 2.5-fold increase in FCF-7 proliferation. SA (0.1-10 um) induced pS2 mRNA levels and the induction was blocked by co-treatment of cells with the anti-estrogen ICI 182,780. SA also induced the formation of the ER-ERE DNA complex measured by electrophoretic mobility shift assay. In summary, these results show that soyasapogenol A is estrogenic, whereas soyasapogenol B is growth inhibitory.