Fig. 7. VEGF distribution is specifically altered in tumors expressing soluble MMP9. (A) VEGF expression was evaluated in tumor sections using GV39M antibody, which recognizes VEGF bound to VEGFR2 (b,e,h,k), and an anti-VEGF mAb, which recognizes the receptor-free form (c,f,i,l). Sections were also stained with anti-CD31 for vessel identification (a,d,g,j). Magnification, x200. (B) Sections from MMP9-wt tumors in untreated (–Dox, a-c) or doxycycline-treated (+Dox, d-f) mice were stained as in A. Magnification, x200.