We observed that VEGF levels in the Ad5-CM, Ad5-Ki67-CM and Ad5-Ki67/IL15-CM treated groups from GL261, U251, and U87 glioma cells and primary cells BT-01 were significantly decreased (Fig. 7), indicating that OAd may inhibit angiogenesis by attenuating VEGF secretion from glioma cells. This evidence concerns the gene VEGFA and central nervous system cancer.