Immunocytochemical analysis of ERα
and VDR in primary and established breast cancer cells. Representative images of cultured tumor-derived (A-C), SUM-229PE (D-F) and BT-474 (G-I) cells are shown. Tumor-derived (A) and SUM-229PE (D) cells were negative for ERα, while BT-474 was ERα positive (G). All cells were positive for VDR (B, E and H) in the cytoplasmic, nuclear and perinuclear regions (brown staining). Negative controls were carried out in the absence of primary antibody for each cell line (C, F and I). Representative pictures are displayed (20 ×).