Fig 6. Elevated expression of ZEB1 promotes angiogenesis in vivo in a nude mouse xenograft model.
(A) A mixture of Matrigel with ZEB1/231 or Control/231 cells was subcutaneously injected into the nude mice (n = 4). Resulting plugs were harvested 10 days later and photographed. (B) A total of 1.5 × 106 ZEB1/231 or Control/231 cells were injected into the mammary fat pads of nude mice (n = 7). Tumor development was followed for 3 weeks, and then the mice were killed. Expression of ZEB1 and CD31 in breast cancer xenografts was examined by immunohistochemical staining. Scale bars, 25 μm. MVD was determined by CD31 staining. Five random fields in each tumor were counted for MVD. **P < 0.01 vs respective control in Student’s t-test. (C) Tumors from ZEB1/231 or Control/231 mice are shown and cross-sectional tumor diameters were measured. Approximate tumor weights (D) and volumes (E) were calculated as described in Materials and Methods. *P < 0.05 vs respective control in Student’s t-test.