Effects of 17β-estradiol (top, left), genistein (top, right), naringenin (bottom, left), and ICI 182 780 (bottom, right) on luciferase gene expression in T47D-KBluc cells cultured in cs-FBS-supplemented medium. Values are expressed as (mean value of induction as a multiple of the value of the vehicle control of four replicate assays) ± (standard error of the mean). The level of luciferase activity was significantly different from the activity observed following treatment (P<0.05). E2, 17β-estradiol; GEN, genistein; NAR, naringenin; ICI, ICI 182 780.