FOLH1 and prostate carcinoma: Both radiolabeled antibody and small molecules have been identified to target PSMA; in particular, the small molecule lysine-ureido-glutamate (Lys-ureido-Glu) motif, which binds to PSMA active site glutamate carboxypeptidase II (NAALADase), has served as the pharmacophore for the recently FDA-approved PSMA-targeting [18F]DCFPyL for imaging prostate cancer with positron emission tomography (PET).