Figure 1.

ERα and ER-regulated genes are overexpressed in aromatase inhibitor-resistant breast cancer cells. Cell lysates were subjected to (A) Western blot for ERα, p-ERα S167, and p-ERα S118 protein expression. Image J software was used to quantify levels of each protein relative to T47D. Quantification is shown below blot. (B) Immunofluorescent imaging. (C) RT-PCR for ERα, and the ER-regulated genes, CCND1, C-Myc, CTSD, pS2 and FOXA1 mRNA. (D) Transcript levels of ERα coactivators of ERα, SP1, SRC1, SRC3, CBP, P300, GATA3 and CITED1, were determined by RT-PCR. Data represent three independent experiments run in triplicate. *** p < 0.001.