Fig. 6: Elevated expression of ZEB1 promotes chemoresistance in vivo in a nude mouse xenograft model

a A total of 1.5 × 10⁶ ZEB1/231 and Ctrl/231 cells were respectively injected into the mammary fat pads of nude mice (n = 5). Tumor development was allowed for 10 days, and then the mice were intraperitoneally injected with 5 mg/kg EPI (once per 2 days) for another 2 weeks. b Tumors from ZEB1/231 and Ctrl/231 mice that were, respectively, treated with EPI and normal saline (NS) are shown. c Approximate tumor weights were measured. ***P < 0.001 vs respective control in Student’s t test. d, e Expression of ZEB1 and ATM in breast cancer xenografts was examined by (d) western blotting and (e) immunohistochemical staining. Cropped blots are shown (full-sized blots are presented in Supplementary Fig. S14). **P < 0.01 vs respective control in Student’s t test. Scale bars, 20 μm