Histological expression of angiogenic factors: VEGF, PDGFR alpha, and HIF-1 alpha in Hodgkin lymphoma

Angiogenesis is a prerequisite for solid tumor growth, but there is relatively limited data regarding Hodgkin lymphoma. The purpose of this study was to examine the immunohistochemical expression of angiogenic and proliferation markers in Hodgkin biopsies in relation to clinical parameters. Immunostaining was performed on 65 Hodgkin biopsies with vascular endothelial growth factor (VEGF), hypoxia inducible factor-1 alpha (HIF-1 alpha), platelet-derived growth factor receptor alpha (PDGFR alpha), Ki-67, and p53. Microvessel density (MVD) was determined by CD31 staining. In all cases, neoplastic cells and reactive background cells were evaluated. The neoplastic population expressed VEGF in 48% of the cases, HIF-1 alpha in 54% of the cases, and PDGFR alpha in 95% of the cases. Both Ki-67 and p53 were positive in neoplastic cells in over 60% of the cases. The MVD had a median of 2.6/0.0625 mm(2) which was not different from normal lymph nodes. VEGF in the non-neoplastic compartment showed increased staining in Ann Arbor stage I-II versus III-IV. In conclusion, VEGF, HIF-1 alpha, and predominantly PDGFRa are expressed in neoplastic cells in the majority of Hodgkin lymphomas. As microvessel formation is not increased in Hodgkin, additional functions of these angiogenic molecules should be investigated. (C) 2008 Elsevier GmbH. All rights reserved.