Fig. 3.
CREB was phosphorylated after treatment with 4-OHT and CREB knockdown partially inhibited 4-OHT-induced IGFBP-1 transcription in MCF-7 cells. (A) Immunoblot analysis of phospho-CREB (S133) after 2 hours of treatment with 4-OHT using the indicated doses. (B) Immunoblot analysis of CREB expression after transfection of CREB-targeting siRNA. (C) Relative IGFBP-1 gene transcription determined by quantitative real-time PCR in CREB knockdown and control cells (NT) after 24 hours of treatment with 4-OHT. *, p<0.05 compared to control, and #, p<0.05 compared to 4-OHT (1μM) treated sample. The results are representative of three independent experiments, and the error bars are SEM.