CD274 and pancreatic neuroendocrine tumor: Moreover, the combination of VEGFR-2 and PD-L1 antibodies induces high endothelial venules (HEVs) to facilitate IFNγ+ CD4+ and IFNγ+ CD8+ lymphocyte infiltration in breast cancer and pancreatic neuroendocrine tumors, finally leading to tumor cell apoptosis and necrosis [148].