ACTIVITIES OF GAMMA-GLUTAMYL-TRANSPEPTIDASE AND ERYTHROCYTE GLUTATHIONE-DEPENDENT ENZYMES IN NASOPHARYNGEAL CARCINOMA PATIENTS AND NORMAL CONTROLS

Plasma gamma-glutamyltranspeptidase (gamma-GT), glutathione peroxidase (GPx) and glutathione reductase (GR) activities were determined in no rmal and nasopharyngeal carcinoma (NPC) patients. No difference in enz yme activities was observed in the three major races of the Malaysian population, i.e. Malay, Chinese and Indian patients. However, plasma g amma-GT, erythrocyte glutathione S-transferase (GST) and GPx activitie s were significantly increased in all NPC patients, while GR activity remained unchanged. Patients with elevated plasma gamma-GT activities also had increased GST and GPx activities. Plasma gamma-GT and GPx act ivities were then found to be affected by treatment. Patients with pla sma gamma-GT activity greater than 70 IU/l had very poor prognoses but patients with decreased gamma-GT activities were found to be in remis sion.