DMP1 impairs in vivo angiogenesis in the CNV model and its overexpression decreases glioma tumor growth and tumor angiogenesis in vivo. (A) Mice were injured by laser shots onto the retina (areas within the dotted lines) and were then subjected to intravitreous injection of DMP1 (500 nmol/L). Eyes were removed after 7 days and the angiogenic response was measured, as described in “Methods.” The quantification represents the measure of total vessel fluorescence surface for each impact. Error bars represent the means ± SEM of 20 impacts of a representative experiment (n = 2). *P ≤ .05 vs control vehicle. (B) The growth of both DMP1-overexpressing (pDMP1) and control (pEmpty) tumors on CAM was documented by biomicroscopy at day 5 after U87-MG cell grafting. A representative tumor for each condition is shown. DMP1 tumors appeared completely white compared with control, in which blood vessels can be seen under the surface. (C) H&E photos of the tumors shown in panel B were taken right under the surface of the tumor (magnification, 40×). Numerous irregular and dilated capillaries (black arrows in the enlarged insert) were visible in control pEmpty tumors but not in DMP1-overexpressing tumors. (D) Specific fluorescein isothiocyanate–lectin staining was used for visualization of blood vessels in the tumors shown in panel B, which confirmed the avascular phenotype of DMP1-overexpressing tumors compared with control pEmpty tumors. Nuclei appear blue after TO-PRO-3 staining (magnification, 40×). (E) Tumor volume was calculated 5 days after grafting for each condition, as described in “Methods.” DMP1 overexpression induced a significant decrease of tumor volume compared with the controls. Results are expressed as the means ± SD of 6 replicates of a representative experiment (n = 3). **P ≤ .005 vs pEmpty. (F) Western blot analysis with an antibody to DMP1 on tumor lysates showing that pDMP1 tumors expressed significantly more DMP1 than control pEmpty tumors.