Estrogen-Deprived Breast Cancer Cell Lines

MCF-7:5C and MCF-7:WS8 cell lines were cultured in phenol red-free Roswell Park Memorial Institute (RPMI) 1640 media supplemented with 10% charcoal-stripped fetal bovine serum (SFS). Media and treatments were replaced every three days. DNA fingerprinting patterns of the cell lines are consistent with the report by the American Type Culture Collection (18 (link)). The MCF-7:5C cell line was chosen for its representation of the estrogen-deprived breast cancer cell and its ability to undergo estrogen-induced apoptosis; the MCF-7:WS8 cell line represents the estrogen-fueled breast cancer cell environment. Estradiol (E₂, Sigma-Aldrich, St. Louis, MO), dexamethasone (Dex, Sigma-Aldrich, St. Louis, MO), medroxyprogesterone acetate (MPA, Sigma-Aldrich, St. Louis, MO), norethindrone acetate (NETA, Sigma-Aldrich, St. Louis, MO), R5020 (Sigma-Aldrich, St. Louis, MO), RU486 (Sigma-Aldrich, St. Louis, MO), 4-hydroxytamoxifen (4-OHT, Sigma-Aldrich, St. Louis, MO), ICI 182,780 (ICI, Sigma-Aldrich, St. Louis, MO), and combinations were dissolved in ethanol and then in media. MPA and NETA were chosen as two representative progestins used in hormone replacement therapy.