Figure 7.

c-Src and EGFR Kinase Activities Are Required for the E2-induced Transcriptional Regulation of STAT5b Target Genes

T47D cells were mock-transfected as in Fig. 3, C and D. After 24 h of serum starvation the cells were pretreated for 1 h with 10 μm PP2, 1 μm AG1478, or their vehicle DMSO, followed by treatment with either control media containing ethanol (Veh) or 10 nm E2 for 4 h. RNA was isolated, reverse transcribed to cDNA, and analyzed by real-time PCR using primers for cyclin D1 (A) or c-Myc (B). Threshold cycle values were normalized for actin, and the data represent the mean ± sem for three (A) or four (B) experiments done in triplicate. Two-way ANOVA was used to determine statistical significance. *, P < 0.01 vs. Veh; #, P < 0.001. vs. E2-stimulated Con. Con, Control.