Soluble vascular endothelial growth factor receptor 1, and not receptor 2, is an independent prognostic factor in acute myeloid leukemia and myelodysplastic syndromes

BACKGROUND. Vascular endothelial growth factor (VEGF) and its receptors (VEGFRs) are major regulators of angiogenesis, which plays a key role in the growth and dissemination of solid tumors and hematologic neoplasms. METHODS. The authors measured the plasma concentrations of soluble VEGFR1 (sVEGFR1) and sVEGFR2 in 133 patients with acute myeloid leukemia (AML) and in 80 patients with myelodysplastic syndromes (MDS) at the time of initial presentation and compared clinical behaviors. RESULTS. A reverse correlation was observed between plasma sVEGFR1 levels and the rate of complete remission (CR) in patients with AML, but not in patients with MDS. In contrast, increased plasma levels of sVEGFR2 were correlated with a lower CR rate in patients with MDS, but not in patients with AML. Cox regression model analysis demonstrated that plasma levels of sVEGFR1, but not sVEGFR2, were independent prognostic factors in both patients with AML and patients with MDS. CONCLUSIONS. The findings suggest that different mechanisms are involved in the pathophysiology of AML and MDS. The concentration of sVEGFR1 and sVEGFR2 in plasma should be considered a significant factor in guiding antiangiogenic therapy for AML and MDS. They may play a role in the pharmacodynamics of therapeutic agents that are supposed to bind directly to these receptors.