Fig. 8.

Different estrogens and SERMs synergistically activate chimeric reporter genes. HeLa cells were cotransfected with 1 μg of GERE-Luc reporter gene and 5 ng each of the expression vectors for ERα-G521R and ERα(GSCKV). One day after transfection, cells were treated with ERα agonist (either 100 nM CE or 100 nM E2), alone or in combination with 10 nM BAZ (A), or 100 nM CE, alone or combined with 10 nM of the indicated SERMs [bazedoxifene (B), 4-hydroxytamoxifen (T), raloxifene, and ICI 182,780 (I)] (B) for 24 hours. Data are presented as relative luciferase activity compared to 100 nM E2 + 10 nM BAZ–treated samples. Values represent the average ± S.E.M. of three independent experiments. The inset in panel (B) is a Western blot showing ER expression levels after 24-hour treatment with the indicated ligands.