The Production of Vascular Endothelial Growth Factor Is Decreased in Acute Myelogenous Leukemia Cases That Are Treated with Chemotherapeutic Agents and Show the Prolonged Bone Marrow Suppression.

Objective: There have been reported that the levels of serum vascular endothelial growth factor (VEGF) were decreased in aplastic anemia cases. We investigated VEGF system after chemotherapy to acute myelogenous leukemia (AML) cases, and determined whether VEGF system influenced the prolonged bone marrow suppression in these cases.

Materials and Methods: Sera and bone marrow cells were prepared from 30 AML cases including 10 cases of AML (M3) at the onset of the disease, after chemotherapy, and the recovery periods, and the concentration of VEGF in sera of the patients and in the conditioned media obtained from bone marrow-cell cultures was measured with ELISA kit (Quantikine; R&D Systems). The expression of VEGF, VEGF receptor type-1 and VEGF receptor type-2 was analyzed with RT-PCR. The biological effect of VEGF on the bone marrow cells which showed the prolonged suppression after chemotherapy was assayed with colony-formation with or without any cytokines.

Result and Discussion: As was reported previously, VEGF levels were significantly increased in M3 cases. In other types of AML cases the levels of VEGF production varied. When patients were given chemotherapy and the bone marrow suppression was prolonged, the production levels of VEGF were significantly diminished less than that observed in AML cases with normal bone marrow recovery. In M3 cases that were treated with all-trans retinoic acid and the prolonged bone marrow-suppression was observed, VEGF production was also suppressed. The expression of VEGFR-1 and -2 was observed in bone marrow cells from prolonged bone marrow suppression cases. In these cases, when bone marrow cells were cultured with VEGF, synergistic effects with G-CSF and EPO were observed with colony-formation assay. These observations indicate that VEGF works on the important role for the hematopoietic recovery after chemotherapy in AML cases.