Fig. 5.

Perfusion imaging of three different genetic variants of the 9L gliosarcoma model. In this study tumor xenografts of VEGF-A over-expressing (VEGF+), under-expressing (VEGF-) and wild-type (VEGF-0) 9L gliosarcoma cells were resected and histologically analyzed (A) Haematoxylin and Eosin (H&E) stained , immunohistochemically stained for Von Willabrand Factor (vWF) and Vascular Growth Factor -DVEGF-D. (B) Tumor specific perfusion were determined using MRI. Blood volume (rCBV) and blood flow were calculated and presented as heat maps. This study demonstrated that although suppression of VEGF-A production in the VEGF- tumors slowed tumor growth initially, blood flow was higher and blood volume was similar to tumors with wild-type expression of VEGF-A. These studies led to the identification of VEGF-D over-expression in the VEGF- tumors that resulted in restoration of angiogenic activity. Courtesy of Moffat et al. [51]