The relationship between γ-glutamyl transpeptidase (GGT) and malignant cell transformation was analyzed in malignant and nonmalignant culture epithelial cell lines derived from rat livers and fibroblastic cell types derived from hamsters and mice. GGT activity was prominent (25 to 90% of cells) in 3 of 5 malignant epithelial liver cell lines. None of the 9 fibroblastic or 4 nonmalignant epithelial cell lines exhibited GGT activity. Our results suggest that by use of GGT activity we can detect in cultured liver cells a significant fraction of the spontaneously or chemically induced malignant cells. Thus, in conjunction with other markers, this marker may help in identifying tumorigenic cells in liver epithelial cultures.
Research sponsored jointly by the National Cancer Institute Contract Y01 CP 70222 under Interagency Agreement 40-636-77 and the Division of Biomedical and Environmental Research, United States Department of Energy, under Contract W-7405-eng-26 with the Union Carbide Corporation.