['To test whether a direct antiangiogenic peptide (anginex) and a vascular endothelial growth factor antibody (bevacizumab, Avastin) can transiently normalize vasculature within tumors to improve oxygen delivery, alleviate hypoxia, and increase the effect of radiation therapy.', 'Tumor oxygenation levels, microvessel density and pericyte coverage were monitored in three different solid tumor models (xenograft human ovarian carcinoma MA148, murine melanoma B16F10, and murine breast carcinoma SCK) in mice. Multiple treatment schedules were tested in these models to assess the influence on the effect of radiation therapy.', 'In all three tumor models, we found that tumor oxygenation levels, monitored daily in real time, were increased during the first 4 days of treatment with both anginex and bevacizumab. From treatment day 5 onward, tumor oxygenation in treated mice decreased significantly to below that in control mice. This "tumor oxygenation window" occurred in all three tumor models varying in origin and growth rate. Moreover, during the treatment period, tumor microvessel density decreased and pericyte coverage of vessels increased, supporting the idea of vessel normalization. We also found that the transient modulation of tumor physiology caused by either antiangiogenic therapy improved the effect of radiation treatment. Tumor growth delay was enhanced when single dose or fractionated radiotherapy was initiated within the tumor oxygenation window as compared with other treatment schedules.'] Does scheduling of radiation with angiogenesis inhibitors anginex and Avastin improve therapeutic outcome via vessel normalization?