Fig. 3

Estrogen activates epithelial-mesenchymal transition in Brca1-deficient and estrogen receptor (ER)-negative tumor cells. a, b p18^−/−;Brca1^MGKO (a) and BRCA1 mutant patient-derived xenograft (PDX) (b) tumors treated with E2 or placebo were analyzed by immunohistochemical staining and western blot. Samples in (a) were derived from four different tumors developed in four individual mice. c The expression of genes indicated in the regenerated p18^−/− tumors treated with E2 and primary p18^−/− tumors was determined by western blot; p18^−/−;Brca1^MGKO tumor was used as a control. d, e p18^−/−;Brca1^MGKO tumor cells were treated with 50 nM E2 and dimethyl sulfoxide (DMSO) for 72 h and 144 h, respectively, and analyzed by fluorescence-activated cell sorting (FACS) (d) and western blot (e). The percentages of vimentin (Vim)-positive cells in (d) are indicated. f p18^−/−; Brca1^MGKO tumor cells were treated with 50 nM E2 or DMSO for 120 h and stained with anti-Vim. g, h p18^−/−;Brca1^MGKO tumor cells were treated with DMSO or 50 nM E2 in the presence or absence of 5 μM 4OHT for 72 h and analyzed by western blot (g) and FACS (h). i SUM149 breast cancer cells were treated with DMSO or 50 nM for 72 h and analyzed by FACS. The percentages of VIM-positive cells are indicated