FOLH1 and prostate cancer: Prostate specific membrane antigen (PSMA) is one such cell surface antigen that it is overexpressed on prostate cancer cells and correlates with increasing disease severity.18 PSMA, a transmembrane glycoprotein with no known endogenous ligand, was first identified in 1987 by Murphy and co-worker19 who raised the monoclonal antibody 7E11-C5 after immunising mice with LNCaP cells (a prostate cell line).