GAMMA-GLUTAMYL-TRANSPEPTIDASE IN NORMAL AND NEOPLASTIC PROSTATE-GLANDS

gamma-Glutamyl transpeptidase (GGT) is a cytoplasmic membrane-bound en zyme important in the metabolism of glutathione and other gamma-glutam yl compounds. It is present in highest levels in the kidney and is als o expressed prominently in reproductive organs such as the prostate gl and. Because GGT has never been examined in prostatic carcinoma, we us ed a new polyclonal antibody (GGT 129) for immunohistochemical localiz ation of GGT in normal prostate gland and 72 prostatic carcinomas. The normal lining secretory cells of ducts and acini showed apical immuno reactivity for GGT, but the basal epithelial cells were negative. Most of the prostatic adenocarcinomas had GGT staining patterns and intens ity similar to those of normal prostatic secretory cells, because the majority of neoplastic cells showed immunopositivity in more than 80% of the adenocarcinomas. In comparing the percentage of cells staining for GGT with clinicopathologic parameters, there was no correlation be tween the number of positive cells and the Gleason score, the percenta ge of intraglandular carcinoma, capsule penetration, or seminal vesicl e invasion. Immunostaining for GGT lacks value as a prognostic factor and does not correlate with standard clinicopathologic parameters. GGT may be important, however, for growth and maintenance of both normal and neoplastic prostatic cells. Modulating GGT levels or administering drags that can be activated by GGT may have therapeutic value.