THE EXPRESSION OF GLUTATHIONE TRANSFERASE ISOENZYMES IN HUMAN-MALIGNANT LYMPHOMA BIOPSIES

Glutathione transferase (GST) activity as well as the expression of di fferent classes of GST isoenzymes were studied in 14 lymphoma biopsies . The GST activity measured with 1-chloro-2,4-dinitrobenzene as a subs trate, varied almost 9-fold. The expression of GSTs classes Pi, Alpha and Mu was studied by immunoblotting using antibodies against human GS Ts. All lymphoma samples displayed high levels of class Pi GST. Class Alpha and Mu GSTs expression varied from not detectable to high. The o bservations were confirmed by quantitation of the three classes of GST with an ELISA technique; Nine of the patients were treated with bifun ctional alkylating agents. A correlation between a clinical complete r esponse to chemotherapy and low expression of GST Alpha was noted (p < 0.02).