In the transgenic rat insulin promoter (RIP)-T antigen (Tag) murine model of metastatic pancreatic neuroendocrine tumor (PNET), which causes carcinogenesis of β-cells of the pancreas and is commonly used to study tumor angiogenesis [135], inhibition of TIE2 on TEMs reduces TIE2+ myeloid infiltration resulting in reduced microvessel density, less vascular permeability, and blockade of tumor cell intravasation mediated by TIE2Hi/VEGF-AHi macrophages [136]. Here, TEK is linked to primitive neuroectodermal tumor.