Figure 3.

VEGFR-1 knockdown significantly inhibits tumor growth and invasion. (A and B) Representative pictures of orthotropic (A) and ectopic (B) control and VEGFR-1 knockdown tumors. Normal right kidney and tumor-bearing left kidney are shown in orthotropic tumors. (C). The weight of VEGFR-1 knockdown tumors is significantly decreased in both orthotropic and ectopic tumors compared with their control. In orthotropic tumors, the weight difference between the tumor-bearing left kidney and the normal right kidney was used as tumor weight. *p < 0.05 vs. orthotropic control. **p < 0.01 vs. ectopic control. (D and E) Representative picture of H&E stain control (D) and VEGFR-1 knockdown (E) tumor sections. (F) The percentage of tumor necrosis was significantly increased in VEGFR-1 knockdown tumors compared with control tumors. *p < 0.01 vs. control. (G-I) Representative pictures of control tumor cells invade adjacent muscle tissue (G, red arrows) in the ectopic model, invade the kidney (H, red arrows) in the orthotropic model, and metastasize to the lung in both models (I, red arrows).