FOLH1 and prostate cancer: Prostate specific membrane antigen (PSMA), which functions on cell membrane as glutamate carboxypeptidase-2 or folate hydrolase, was shown to be over-expressed in prostate cancer cells (12), which led to the introduction of Ga-68 labeled urea-based PSMA inhibitor (Ga-68-PSMA-HBED-CC) as a novel positron emission tomography (PET) tracer used for staging of patients with prostate cancer with high accuracy, for detection of LN and organ metastasis, as well as for detection of residual or recurrent local disease (13).