Figure 9.

Histological evaluation of MDA-MB-231-luc tumor xenografts after OXi8007 administration confirmed vascular shutdown. (A) Hoechst 33342 dye was infused into mice (IV) 1 minute prior to sacrifice to selectively stain perfused regions. Tumor sections revealed tumor perfusion (top panel, blue) based on distribution of Hoechst 33342 and vascular structure based on Cy3-conjugated secondary antibody staining of CD31 (bottom panel, red) to show the presence of endothelial cells. There is general initial perfusion in vehicle treated mice, significant reduction of perfusion 6 h post administration, and only intense peripheral perfusion at 24 h post administration. The pattern of CD31 staining matches the perfusion seen with the Hoechst 33342 staining. Bars, 1000 µm. (B) 20× images of baseline and 24 h treated tumor sections stained with Hoechst 33342 dye and Cy3-conjugated secondary antibody for CD31. Images are taken from area corresponding to white rectangles in (A). Bars, 100 µm. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)