[Polyamine levels and biosynthesis in leukocytes during leukemic transformation]

The content of polyamines, rate of their biosynthesis, and activity of ornithine decarboxylase (ODK), the key regulatory enzyme in the polyamine biosynthetic pathway, have been studied in the leukocytes of healthy persons and of patients with various forms of leukemia. The polyamine levels and the rate of their biosynthesis were considerably higher in lymphocytes than in granulocytes. In leukemias, as the cell population rejuvenated, both the polyamine content and the spermidine/spermine ratio were found to be markedly elevated approaching the maximal values in human blast cells of K-562 line. The leukemic transformation of myeloid cells was associated with the increase in the ornithine decarboxylase activity and in the rate of polyamine synthesis, whereas these items were significantly lowered in lymphoid leukemic cells. The changes observed in polyamine metabolism in leukemias are considered to be related to the proliferative and biosynthetic activity of the cells.