| The Inhibition of the Estrogenic Effects of Pesticides and Environmental Chemicals by Curcumin and Isoflavonoids Surendra P. Verma,1 Barry R. Goldin,1 and Peck S. Lin2 1Department of Family Medicine and Community Health, Tufts University School of Medicine, Boston, MA 02111 USA; 2Department of Radiation Oncology, Medical College of Virginia, Richmond, VA 23298 USA Abstract Many environmental chemicals and pesticides have been found to be estrogenic and have been shown to stimulate the growth of estrogen receptor-positive (ER-positive) human breast cancer cells. Since it is difficult to avoid human exposure to environmental estrogens, a potentially important area of research is the development of dietary strategies to prevent the stimulated growth of breast tumors by environmental estrogens. In this context, the inhibitory action of curcumin and a combination of curcumin and isoflavonoids were studied in ER-positive human breast cancer cells (MCF-7 and T47D) and ER-negative MDA-MB-231 cells induced by the pesticide o,p´-DDT and the environmental pollutants 4-nonylphenol and 4-octylphenol. The median inhibitory concentration (IC50) for curcumin in T47D cells was 10 µM when measured at either a 48-hr or a 6-day incubation time. The IC50 value for curcumin was within the 8-10 µM range for inhibiting the growth of T47D cells induced by a 10-µM concentration each of 4-nonylphenol, 4-octylphenol, and o,p´-DDT. The IC50 for curcumin in MCF-7 cells induced by 10 µM of either o,p´-DDT, 4-octylphenol, or 4-nonylphenol were 9, 39, and >50 µM, respectively. A combination of curcumin and isoflavonoids was able to inhibit the induced growth of ER-positive cells up to 95%. For MDA-MB-231 cells, the IC50 for curcumin was 17 µM, which was reduced to 11 µM in the presence of 25 µM genistein. Curcumin and genistein induce drastic changes in the morphological shape of both ER-positive and ER-negative cells. Data presented here indicate that a mixture of curcumin and isoflavonoids is the most potent inhibitor against the growth of human breast tumor cells. These data suggest that combinations of natural plant compounds may have preventive and therapeutic applications against the growth of breast tumors induced by environmental estrogens. Key words: curcumin, estrogenic chemicals, human breast cancer cells, isoflavonoids, pesticides. Environ Health Perspect 106:807-812 (1998) . [Online 13 November 1998] http://ehpnet1.niehs.nih.gov/docs/1998/106p807-812verma/ abstract.html Address correspondence to S.P. Verma, Department of Family Medicine and Community Health, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111 USA. These studies were supported by NIH grant RO1 CA54349 (to B.R.G.) . Received 9 June 1998 ; accepted 28 July 1998. The full version of this article is available for free in HTML format. |