(A) ERE-reporter gene activity. MCF-7:PF cells were transfected with ERE firefly luciferase and renilla luciferase plasmids as in Materials and Methods. (B), (C) Expression of classical ER-target genes. MCF-7:PF cells were treated with vehicle (0.1% EtOH), E2 (10−9 mol/L), 4-OHT (10−6 mol/L), and E2 (10−9 mol/L) plus 4-OHT (10−6 mol/L) for 24 hours. Expression of c-Myc (B) and GREB1(C) was quantitated by real-time RT-PCR. p<0.05, * compared with control, p<0.001, ** compared with control. (D), (E) Expression of non-classical ER-regulated genes. RNA samples were the same as in (B) and (C). Expression of c-Fos (D) and c-Jun (E) was quantitated by real-time RT-PCR. p<0.05, * compared with control.