Activities of enzyme transducing extracellular signals--gamma glutamyltransferase and enzymes metabolizing glutathione in acute lymphoblastic and myeloid human leukemias.

The ectoenzyme gamma glutamyltransferase (GGT) a second messenger generating enzyme activity on the cytoplasmic membrane was biochemically analyzed in leukemic cells from patients with acute lymphoblastic and myeloid leukemias. The lower mean activity--0.594 IU/mg protein was noticed in patients with acute lymphoblastic leukemias (ALL), while the higher--0.956 IU/mg protein was found in acute myeloid leukemia patients (AML) in serum and 0.151 IU/mg protein in polymorphonuclear cells. The levels of the activity of glutathione reductase (GR) were increased but the activities of glutathione peroxidase (GSH Px) were significantly decreased in serum of leukemia patients.