Gamma glutamyl transpeptidase activity in carcinogen-induced epithelial lesions of rat kidney.

A marked decrease of gamma glutamyl transpeptidase activity in rat renal cell neoplasms and preneoplastic tubular lesions induced by exposure to carcinogens was demonstrated. The data suggest that rat renal cell tumorigenesis might require a transformation to fetal characteristics in enzymatic activity such as is found in rat liver cell tumorigenesis, although the nature of the change in activity is quite different. The findings also suggest that persistence of weak gamma glutamyl transpeptidase activity of renal tubular cells during tumorigenesis may provide a useful histoenzymatic marker and indicate a biological reversion of the membrane function during the process of renal cell tumorigenesis.