Characterization of gamma-glutamyltranspeptidase from human exocrine pancreatic carcinomas

Two different types of gamma-glutamyltranspeptidase (gamma-GTP) have been found in normal human pancreas following bromelain treatment. On the other hand, three human pancreatic ductal cell carcinomas have only a single type of gamma-GTP upon analysis with polyacrylamide gel electrophoresis, anion-exchange column chromatography and isoelectric focusing. Carcinoma gamma-GTPs were almost identical to one of the two types of normal pancreatic gamma-GTPs. The gamma-GTP from pancreatic carcinomas bound to anion-exchange column and was eluted at the same NaCl fractions as normal pancreatic gamma-GTP. The properties of pancreatic carcinoma-gamma-GTP, as assessed by binding to concanavalin A and lentil lectin affinity columns, were also similar to one of the two enzymes of normal pancreas. No apparent difference in isoelectric points was found between the carcinoma gamma-GTPs and one of the two normal pancreatic gamma-GTPs.