The closest homolog to Plxdc2, Plxdc1 was initially identified as overexpressed in blood vessels of solid human tumors [25], resulting in the original terminology tumor endothelial marker 7 (TEM7, Plxdc1) and tumor endothelial marker 7 related (TEM7R, Plxdc2) [26]. Here, PLXDC1 is linked to neoplasm.