FLT1 and central nervous system cancer: SPARC is capable of binding to VEGF, and in doing so, specifically inhibits VEGF-VERGFR1 signaling of endothelial cells.17 Gliomas also express VEGFR1.20, 21 Therefore, we evaluated the status of SPARC-VEGF interaction by coimmunoprecipitation and the status of VEGFR1 expression in our glioma model.