THE HISTOCHEMICAL AND BIOCHEMICAL STUDIES ON γ-GLUTAMYL TRANSPEPTIDASE IN HUMAN GASTRIC CANCER

Abstract

In order to study γ-glutamyl transpeptidase (GGT) in gastric cancer and intestinal metaplasia, amount of GGT in each tissue (gastric cancer, intestinal metaplasia, and fundic gland mucosa) and the localization of GGT were determined.
The resected tissues were homogenized with Tris-HCL buffer (3mM, pH7.4). After centrifugation (700×g, 10min), GGT activity was measured in supernate of each tissue. The value of GGT was 24.9± 15.2(U/g. protein) in the cases of differentiated carcinoma, 6.0±2.4(U/g. protein) in the cases of undifferentiated carcinoma, 8.2±1.3 (U/g. protein) in fudic gland mucosa. In intestinal metaplasia, the localization of GGT activity was observed in all cases, which coincided with alkaline phosphatase.
In gastric cancer, the frequency of GGY localization increased statistically in differentiated carcinoma, compared with undifferentiated carcinoma. The localization was observed at luminal border and mucus in the cases of differentiated carcinoma, while at cytoplasma in undifferentiated carcinoma.
Although the GGT localization was various, many tissues of gastric cancer showed positive for GGT. It is therefore considered that GGT is an important marker protein for studying on phenotypes of gastric cancer and intestinal metaplasia.