KDR and primitive neuroectodermal tumor: In the pancreatic neuroendocrine tumour model and the polyoma middle T oncoprotein (PyMT) breast cancer model (RT2-PNET), the combination of both anti-VEGFR2 antibodies and PDL–1 antibodies stimulated the formation of specialised vessels called High Endothelial Venules (HEVs), which contribute to lymphocyte trafficking and improved T-cell infiltration (129).