Serine and Aspartic Acid Metabolism in Leukemic Leukocytes: Correlation to Effectiveness of Therapy

Leukocytes from patients with acute granulocytic leukemia (AGL), acute monocytic leukemia (AMoL) and blastic crisis of chronic granulocytic leukemia (BC) were incubated with serine-U-C¹⁴ or aspartic acid-U-C¹⁴. The metabolism was followed by determination of radioactivity of CO₂, lipids, proteins, organic acids, and nucleotides. Leukemic leukocytes in AGL, AMoL, and BC exhibit high serine utilization compared to lymphocytic leukemias. Significant changes in the metabolic pattern of the leukocytes from patients with chronic granulocytic leukemia (CGL) preceded the onset of blastic crisis. Serine utilization remained abnormal in two patients with AGL after complete remission was achieved. Low conversion of serine to CO₂ in AMoL was associated with achievement of complete remission and long survival time. Aspartic acid was most actively metabolized by leukemic cells in BC. The results of these studies indicate that the metabolic pattern of serine and aspartic acid varies with the type of leukemic cell. There is evidence that mature polymorphonuclear (PMN) leukocytes in the blood of leukemic patients may possess an abnormal metabolism.