We measured activity and content of cathepsin B in tumor tissues, liver, and spleen in mice with Lewis adenocarcinoma and LS-lymphosarcoma. Cathepsin B activity in Lewis adenocarcinoma cells was lower than in LS-lymphosarcoma cells, which was probably related to differences in their metastatic properties. Antitumor therapy increased activity and content of cathepsin B in tumor tissues. Changes in the content and activity of cathepsin B in tumor tissues can serve as a prognostic criterion for tumor regression during therapy. Cathepsin B is probably involved in apoptosis of tumor cells during chemotherapy of lymphosarcoma-LS with cyclophosphamide.
The isoenzymes of glucose-6-phosphate dehydrogenase (G-6-PD, EC 126.96.36.199) was studied in hyaloplasm and mitochondria of the liver, myocardium, skeletal muscle, spleen and adrenals of alloxan diabetic rabbits. The most significant changes were found in the liver hyaloplasm: one of the minor isoenzymes, isoenzyme "C", disappears and the zone of the main isoenzyme "E" decreases significantly in comparison with the control. It was found that the intensity of these changes depends on the glycemia level in the diabetic animals.