FOLH1 and kidney neoplasm: PSMA is a 750 amino acid, type II transmembrane glycoprotein (100–120 kDa) with an intracellular component, a transmembrane component, and a large extracellular domain, that has been shown to be highly expressed in the proximal tubules of normal kidney tissues and is differentially expressed in the tumor-associated neo-vasculature of different renal tumors [30].