Effect of ERβ on expression of receptor tyrosine kinases upstream of Akt. (A) T47-DERβ cells. EGFR, epidermal growth factor receptor; HER2, proto-oncogene c-ErbB-2; HER3, receptor tyrosine kinase erbB-3. (B) T47-DPBI cells (C) MCF-7ERβ cells. For Figures 1A to 1C, cells were treated for 4 days with 10 ng/mL or 0.01 ng/mL doxycycline in the presence or absence of 10 nM DPN and cell lysates were analyzed by immunoblotting. (D) Immunofluorescence study of T47-DERβ cells treated for 4 days with 10 ng/mL (-ERβ) or 0.01 ng/mL (+ERβ) doxycycline. Cells were stained with anti-HER2 antibody. Scale bar, 10 μm.