Biochemical and histochemical studies on variant γ-glutamyl transpeptidase in human gastric cancer

γ-glutamyl transpeptidase(GGT) that increase in gastric cancer was compared immunologically and biochemically with that from kidney. By means of the active inhibition test and the double immuno-diffusion test, it was observed that gastric cancer GGT had the similar immunological properties to kidney GGT. But in the studies of isoelectric focusing and Con-A column chromatography, gastric cancer GGT differed from kidney GGT in sialic acid contents and suger chain. On the other hand, histological study indicated that various mechanism, gene expression, proliferative state etc., was concerned with GGT appearance in gastric cancer. These data suggested that GGT was an useful enzyme to study enzyme transformation in tumorgenicity and that the study of suger chain meight develope a new method for the diagnosis of gastric cancer.