Fig. 1
From: Classification of Breast Cancer Cells on the Basis of a Functional Assay for Estrogen Receptor
Anti-hormone sensitivity of T47D and 21PT cells. T47D (A) and 21PT (B) cells (1 × 104) were plated in duplicate in 96-well cloning tissue culture dishes either in DMEM medium supplemented with 10% dextran coated charcoal-treated FBS (DCC), 1 µg/ml insulin and 12.5 ng/ml EGF, or in complete medium (FBS). After 48 hr the medium was removed and fresh DCC medium containing the indicated concentrations of 17-β estradiol (E2), ethynylestradiol (EE2), tamoxifen (TAM), or ICI-182,780 were added. The control wells contained the same volume of solvents, 95% ethanol for E2, EE2, and ICI-182,780, and DMSO for TAM. The medium was changed every 2 days with the same fresh media. After 5 days of treatment, viability of cells was determined by the MTT assay (54). The percent viability of cells in the presence of the antihormones was expressed as percentage of the untreated control. This experiment was repeated twice.