Expression of arylsulfatase B variant from leukocytes in chronic myelogenous leukemia related to chemotherapy

Lysosomal arylsulfatase B of human leukocytes consisted of two forms; a basic form (B) and a variant form (B1) which is phosphorylated at the carbohydrate chains of the B form (Uehara, Y., Gasa, S., Makita, A., Sakurada, K., and Miyazaki, T. (1983) Cancer Res. 43, 5618-5622). The amounts of the variant form relative to the basic form were considerably increased in leukocytes of chronic myelogenous leukemia (CML). The present communication demonstrates that, upon chemotherapy of the patients with CML, degree of phosphorylation as well as the relative amounts of the phosphorylated variant form of CML leukocytes are markedly decreased concomitantly with an increase of the basic, less phosphorylated form. This effect of chemotherapy on the variant form preceded to clinical improvement of the CML patients, suggesting that the relative amount of the phosphorylated enzyme will be a potential prognostic indicator for the therapeutic effect of CML.