PHOSPHOGLYCERATE MUTASE, 2,3-BISPHOSPHOGLYCERATE PHOSPHATASE AND ENOLASE ACTIVITY AND ISOENZYMES IN LUNG, COLON AND LIVER CARCINOMAS

We have compared the levels of phosphoglycerate mutase, 2,3-bisphospho glycerate phosphatase and enolase activities and the distribution of t heir isoenzymes in normal colon, liver and lung tissues, and in colon, liver and lung adenocarcinoma, lung squamous cell carcinoma and lung carcinoid. Ail tumours presented higher phosphoglycerate mutase and en olase activities and lower 2,3-bisphosphoglycerate phosphatase activit y than the normal tissues. No changes were observed in the phosphoglyc erate mutase isoenzyme patterns analysed by cellulose acetate electrop horesis. All specimens contained mainly type BE isoenzyme, traces of t ype MB isoenzyme and no type MM isoenzyme. However, the tumours had de creased levels of 2,3-bisphosphoglycerate mutase and 2,3-bisphosphogly cerate mutase-phosphoglycerate mutase hybrid enzyme. Determined by aga rose gel electrophoresis, aa-enolase was the isoenzyme predominant in normal lung, colon and liver tissue, although alpha gamma- and gamma g amma-enolase were also present in all tissues. In colon, liver and non -endocrine lung tumours, the proportions of alpha gamma- and gamma gam ma-enolase decreased. In contrast, in carcinoid tumours of the lung, t he proportions of these isoenzymes increased.