Effect of CXCR7 silencing on tumor growth. About 2 × 106 CXCR7shRNA, control and NC cells were inoculated subcutaneously into the back of five different nude mice in each group. On day 32 after tumor inoculation, the mice were sacrificed. A. representative pictures from each group of mice bearing tumors. B. tumor volume was measured at the indicated days. Data shown are means ± SD (n = 5). *p < 0.05 (as compared with both control and NC tumors). C. weight of the tumor was determined after dissection at the end of the experiment. As shown, both tumor volume and tumor weight were dramatically decreased as the consequence of CXCR7 silencing. Data shown are means ± SD (n = 5). *p < 0.05 (as compared with both control and NC tumors). D. tumor sections were examined for MVD. Tumor vessels in a three randomly selected fields were counted in tumor sections in each group. Data shown are means ± SD. *p < 0.05 (as compared with control and NC tumors). E. inhibition of tumor angiogenesis by silencing CXCR7. Tumor sections were stained with anti-CD31 antibodies. Positive staining is indicated by an arrow.