¹Department of Medicine/Hematology and Oncology, University of Muenster, Muenster, Germany

Correspondence: Dr RM Mesters, Department of Medicine/Hematology and Oncology, University Hospital Muenster, Albert Schweitzer Str. 33, D-48129 Muenster, Germany. E-mail: mesters@uni-muenster.de

²Present address: Clinic for Thoracic Diseases at the University of Heidelberg, Department of Oncology, Heidelberg, Germany.

Received 2 June 2006; Revised 31 July 2006; Accepted 2 August 2006; Published online 31 August 2006.

Abstract

Neuropilin-1 (NRP-1), a vascular endothelial growth factors and semaphorin receptor functioning as mediator of angiogenesis and neuronal guidance, is expressed by various solid tumors. The importance of NRP-1 in hematological malignancies such as acute myeloid leukemia (AML) remains to be elucidated. Therefore, we determined NRP-1 expression by immunohistochemical analysis of bone marrow biopsies of patients with newly diagnosed, untreated AML. The expression of NRP-1 was significantly increased in AML patients (n=76; median 12.9 arbitrary units (a.u.)) as compared with controls (n=38; median 2.75 a.u.). Survival was significantly poorer in patients with high (>median) versus low (median) NRP-1 expression levels with 5-year overall survival rates of 16.9 versus 49.6% (P=0.050). In conclusion, our data provide evidence of increased NRP-1 expression in AML with significant correlation to survival. Thus, NRP-1 might constitute a promising target for antileukemic and antiangiogenic treatment strategies in AML.