END and ENL induce nuclear translocation of estrogen receptor (ER) and increase the expression of ER-responsive genes. (A,B) MCF7 cells were treated with 1 μM END and 1 μM ENL for different time intervals as indicated and localization of ER was examined using immunocytochemistry. (C) MCF7 cells were treated with 1 μM END, 1 μM ENL, and 100 nM E2 followed by nuclear and cytoplasmic extraction and immunoblot analyses for ER expression. (D,E) MCF7 cells were treated with 1 μM END, 1 μM ENL, and 100 nM E2 for indicated time intervals. Protein lysates and total RNA were isolated and examined for the expression of ER-responsive genes as noted.