VEGFA and neoplasm: Upon stimulation, TIE2+ macrophages at TMEM doorways secrete vascular endothelial growth factor-A (VEGFA), leading to the localized disruption of the underlying endothelial adherens and tight junctions and, as a consequence, the opening of the vessel wall (TMEM-associated vascular opening, or TAVO), localized vascular leakiness, and subsequent tumor cell transendothelial migration and intravasation1.