Figure 4
Cutting off tumor blood supply could not prevent the formation of distant metastases. (A,D) After implantation of a 3.0 μm membrane-wrapped tumor or an un-wrapped tumor for 1, 2, 3, and 4 weeks, the lungs of the tumor-bearing mice were harvested and fixed with 4% paraformaldehyde (PFA) to observe the formation of lung metastases. (B,E) The number of tumor colonies on the surface of the lung was counted. (C,F) The metastatic lesions were quantified as the percentage of metastatic areas per lung area. The data are presented as scatter plots with means ± SD. The number of dots indicates the “n” of each group. (G) Lung metastases from the primary orthotopic breast tumor. (H,I) Comparison of the metastatic colonies and metastatic area of the lung surface. Orthot: the orthotopic mammary 4T1 tumor; No-M: the implantation of an un-wrapped tumor mass; M + 3.0 μm: the implantation of a tumor mass wrapped with a 3.0 μm membrane. (J) The Kaplan-Meier survival analysis of the mice bearing an orthotopic tumor or implanted tumor (n = 10 per group). The data were analyzed using a log-rank test. The p values are shown within the figure.
