Fig. 5
From: Classification of Breast Cancer Cells on the Basis of a Functional Assay for Estrogen Receptor
Hormone dependency of ER-ERE formation. A comparative study of hormone dependency of ER-ERE interaction was investigated with nuclear extracts from MCF-7 (A), 21PT (B), MS (C) and T47D (D) cells. Cells were grown either on stripped medium (DCC, DMEM without phenol red supplemented with 10% stripped FBS) with indicated concentrations of E2 added for the last 2 hr before harvesting, or complete medium (C, DMEM with phenol red and supplemented with 10% FBS only). Nuclear extracts were prepared and protein-DNA binding reactions were carried out with 2 µg of nuclear proteins and 32P-ERE and incubated at room temperature for 30 min followed by EMSA as described above. The arrow shows the position of the retarded 32P-ER-ERE complex.