FLT1 and neoplasm: VEGF‐A intracellular signaling activities are mediated by the activation of VEGF receptors (VEGFR‐1, VEGFR‐2) which can be expressed on endothelial cells, tumor cells, and some immune cells.[22, 23] We found that VEGFR‐1 and VEGFR‐2 were readily detected on THP‐1 monocytes (Figure S3e, Supporting Information).