2,3,7,8-Tetrachlorodibenzo-p-dioxin exhibits antiestrogenic activity and induces cytochromes P-450 in estrogen-dependent MCF-7 human breast-cancer cells. To determine whether induction of 2- or 16α-hydroxylation of 17β-estradiol has a role in this antiestrogenic activity, MCF-7 cells which were exposed to this xenobiotic for 72 hrs were incubated with either [2-3H] or [16α-3H] 17β-estradiol and the extent of tritiated H2O formation, indicative of site-specific hydroxylation, was determined. 2,3,7,8-Tetrachlorodibenzo-p-dioxin-treated MCF-7 cultures showed an 8-fold increase in 2-hydroxylation and a 2-fold increase in 16α-hydroxylation. These results support the suggestion that increased hydroxylation of 17β-estradiol may have a role in the antiestrogenic activity of 2,3,7,8-tetrachlorodibenzo-p-dioxin in MCF-7 cells.
|Number of pages||6|
|Journal||Biochemical and biophysical research communications|
|Publication status||Published - 1988 Dec 15|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology