Fig. 4

Dll4 deletion reduces sorafenib efficacy against DMBA/TPA- mediated skin papillomas. a Treatment schematic diagram. b Tumor volume changes in WT and Dll4^+/− mice during the treatment with vehicle or sorafenib. c Vascular response examined by double PECAM/α-SMA immunostaining indicating reduced sprouting and recruitment of perivascular cells in sorafenib-treated vs. vehicle-treated WT mice, as well as enhanced endothelial proliferation, however, with increasingly impaired vessel wall assembly in sorafenib-treated Dll4^+/− vs. WT mice