Fig. 4From: Antiangiogenic agents targeting different angiogenic pathways have opposite effects on tumor hypoxia in R-18 human melanoma xenograftsTumor hypoxia. a-c, Immunohistochemical preparations stained for pimonidazole to visualize hypoxia of untreated (a), properdistatin-treated (b), and sunitinib-treated R-18 tumors (c). Scale bars, 1 mm. d, Hypoxic area fraction in untreated, properdistatin-treated, and sunitinib-treated R-18 tumors. Columns, means of 5–9 tumors; bars, SEBack to article page