Figure 3.

ER beta promoter activity is up-regulated by mibolerone through an ARE site. (A) Upper panel, schematic representation of construct of the ER beta gene promoter used in this study. Bottom panel, plasmid containing ER beta promoter fragment was transiently transfected in MCF-7 and ZR-75 cells treated with vehicle (−) or Mib 10 nM in the presence or absence of 1 μM OH-Fl. *, P <0.05 compared to vehicle-treated cells; *, P <0.05 compared to Mib-treated cells. (B, C) Left panel, schematic representation of constructs of the ER beta gene promoter used in this study. Right panel, plasmids containing ER beta promoter fragments were transiently transfected in cells treated with vehicle (−) or Mib 10 nM. After 24 hours of transfection, luciferase activities were normalized to the Renilla Luciferase as the internal transfection control and data were reported as fold change. The values represent the means ± S.D. of three different experiments each performed in triplicate. pGL3: basal activity measured in cells transfected with pGL3 basal vector. *, P <0.05 compared to vehicle-treated cells; *, P <0.05 compared to Mib-treated cells. ARE, androgen response element; ER, estrogen receptor.