In vivo growth of mantle cell lymphoma xenografts in immunodeficient mice is positively regulated by VEGF and associated with significant up-regulation of CD31/PECAM1

Folia Biol (Praha). 2013;59(1):26-31.

Abstract

Mantle cell lymphoma (MCL) is an aggressive lymphoma subtype with dismal prognosis. New treatments are needed to improve outcome of relapsed/ refractory disease. Recently, several drugs targeting at least partially the process of angiogenesis have been successfully tested in the therapy of MCL. Molecular mechanisms that regulate MCL-induced angiogenesis and that might represent potential new druggable targets remain, however, incompletely understood. We established two mouse models of human MCL by subcutaneous xenotransplantation of JEKO-1 and HBL-2 cell lines into immunodeficient mice. Histological analyses of xenografts confirmed their neovascularization. The growth of xenografts was significantly suppressed by single-agent therapy with bevacizumab, monoclonal antibody targeting vascular endothelial growth factor (VEGF). Subsequently, we analysed expression of 94 angiogenesis related genes in ex vivo isolated JEKO-1 and HBL-2 cells compared to in vitro growing cells using TaqMan low-density arrays. The most up-regulated genes in both JEKO-1 and HBL-2 xenografts were genes encoding platelet/endothelial cell-adhesion molecule (CD31/PECAM1), VEGF receptor 1 (FLT1), hepatocyte growth factor (HGF), angiogenin (ANG) and transcription factor PROX1. The most downregulated genes in both JEKO-1 and HBL-2 xenografts were midkine (MDK) and ephrine B2 (EPHB2). In summary, our results demonstrate an important role of angiogenesis in the biology of MCL and provide preclinical evidence of potent anti-MCL activity of bevacizumab. In addition, gene expression profiling of 94 angiogenesis-related targets revealed several in vivo up-regulated and down-regulated transcripts. The most differentially expressed target in both MCL tumours was CD31/PECAM1. Whether any of these molecules might represent a potential druggable target in MCL patients remains to be elucidated.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Proliferation
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Lymphoma, Mantle-Cell / genetics
  • Lymphoma, Mantle-Cell / metabolism*
  • Lymphoma, Mantle-Cell / pathology*
  • Mice
  • Mice, SCID
  • Neovascularization, Pathologic
  • Platelet Endothelial Cell Adhesion Molecule-1 / metabolism*
  • Up-Regulation*
  • Vascular Endothelial Growth Factor A / metabolism*
  • Xenograft Model Antitumor Assays*

Substances

  • Platelet Endothelial Cell Adhesion Molecule-1
  • Vascular Endothelial Growth Factor A