shown by endomucin staining (***p,0.001). C, Immunocompe- tent mice heterozygous for a spontaneous model of pancreatic cancer received extended 8-week therapy with saline, 25 mg/kg/ week mouse chimeric r84 (mcr84), or 50 mg/kg/week sunitinib. There was a trend towards a decrease in final pancreas weight at time of sacrifice in mcr84-treated animals as compared to control, although this decrease failed to reach statistical significance. Found at: doi:10.1371/journal.pone.0012031.s004 (3.99 MB TIF) Figure S3 Immunohistochemical analysis of r84 efficacy and toxicity profile following long-term therapy. NOD/SCID mice bearing subcutaneous PANC-1 tumors received long-term 12- week therapy with 50 mg/kg/week r84 or a control IgG. A, Long- term r84 therapy in TB or NTB animals did not change pancreatic islet vessel density (endomucin, green) or pericyte distribution (NG2, red) as compared to age-matched Na¨ıve animals (**p,0.01). Blood chemistry analysis of serum samples collected from mice at sacrifice revealed no change in glucose levels between groups (B). TB or NTB animals receiving long-term antibody therapy with r84 or a control IgG and Na¨ıve animals References 1. Folkman J (1971) Tumor angiogenesis: therapeutic implications. N Engl J Med 285: 1182–1186. 2. Roskoski R, Jr. (2007) Vascular endothelial growth factor (VEGF) signaling in tumor progression. Crit Rev Oncol Hematol 62: 179–213. 3. Dineen SP, Lynn KD, Holloway SE, Miller AF, Sullivan JP, et al. (2008) Vascular endothelial growth factor receptor 2 mediates macrophage infiltration into orthotopic pancreatic tumors in mice. Cancer Res 68: 4340–4346. 4. Brekken RA, Huang X, King SW, Thorpe PE (1998) Vascular endothelial growth factor as a marker of tumor endothelium. Cancer Res 58: 1952–1959. 5. Brekken RA, Overholser JP, Stastny VA, Waltenberger J, Minna JD, et al. 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