Isoenzyme variants of nonspecific esterases in chronic myelocytic leukemia and in blastic crisis

The isoenzymes of nonspecific esterases have been examined with polyacrylamide gel electrophoresis in 10 patients with chronic myelocytic leukemia (CML) and 10 with blastic crisis (BC) in respect to normal subjects. In patients with active CML the recurrent loss of fast bands was detected, while in patients in remission the isoenzyme variants are similar to those found in normal subjects. Different isoenzyme variants which are similar to those found in acute leukemia were detected in patients with BC of differenct morphological type with the exception of BC of megakaryoblastic type. The possible meaning of such variants in relation to an early identification of malignant proliferating clones, is discussed.