Fig. 4
Changes in vasculature of 4T1 tumors after sorafenib treatment. a Exemplary Ktrans and T1 maps post-gadofosveset injection of sorafenib-treated 4T1 tumors compared to untreated controls. b Area under the curve (AUC), maximum slope (slopemax), Ktrans and ∆T1 analyses indicating increasing tumor perfusion and permeability parameters on day six, with a consecutive decrease to day nine. Each dot represents one animal, with horizontal lines indicating the mean. c H&E staining of 4T1 tumor sections showing increasing areas of necrosis after treatment, while CD31 expression is reduced. Scale bars represent 50 µm. d Transmission electron micrographs (TEM) of 4T1 tumors. Untreated 4T1 tumors show a thin endothelial layer with short interruptions (dashed circles). After sorafenib treatment, endothelial layers are overall more intact with less interruptions (dashed circles). Electron dense contrast agent is visible intravasal (white circle) and extravasal (black circles), with reduced extravasated contrast agent from day six to day nine. Scale bars represent 1 µm. e erythrocyte, el endothelial layer, bl basal lamina, cf collagen fibrils. **p < 0.01, ***p < 0.001, ****p < 0.001