gms | German Medical Science

60. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit den Benelux-Ländern und Bulgarien

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

24. - 27.05.2009, Münster

Tissue Microarray (TMA)-based expression analysis of the Chondroitin Sulphate Proteoglycan NG2 in gliomas

Meeting Abstract

  • R. Ahmadi - Neurochirurgische Universitätsklinik Heidelberg
  • J. Bucher - Neurochirurgische Universitätsklinik Heidelberg
  • N. Becker - DKFZ Heidelberg
  • J. Trotter - Institut für Biologie, Universitätsklinikum Mainz
  • C. Herold-Mende - Neurochirurgische Universitätsklinik Heidelberg
  • A. Unterberg - Neurochirurgische Universitätsklinik Heidelberg

Deutsche Gesellschaft für Neurochirurgie. 60. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit den Benelux-Ländern und Bulgarien. Münster, 24.-27.05.2009. Düsseldorf: German Medical Science GMS Publishing House; 2009. DocP14-02

DOI: 10.3205/09dgnc400, URN: urn:nbn:de:0183-09dgnc4008

Veröffentlicht: 20. Mai 2009

© 2009 Ahmadi et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielfältigt, verbreitet und öffentlich zugänglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Objective: NG2 is a transmembrane glycoprotein expressed by different subpopulations of glial cells including oligodendroglial precursor cells. It is supposed to be involved in the regulation of proliferation, differentiation and/or migration of neural stem/progenitor cells and their derivatives in the adult brain germinal niches. However, knowledge about NG2 expression under pathological conditions e.g. in gliomas is still poor. Therefore, in the present study we aimed to explore the expression of NG2 and a potential correlation to clinical outcome in a large series of gliomas.

Methods: Representative biopsies of 281 paraffin-embedded tumors including 34 recurrent tumors as well as 35 low grade gliomas WHO II°, 13 anaplastic astrocytomas WHO III°, and 199 glioblastomas WHO IV were collected on a tissue microarray (TMA). Clinical follow-up data regarding survival rates and treatment regimens were available in a database. TMA was used for immunohistochemical staining with NG2-specific antibodies. The correlation of staining patterns with survival data was computed using a multivariate Cox proportional hazard model.

Results: Expression of NG2 was evaluated in staining levels of 1–7 (0–100% positive cells). Surprisingly, the proportion of NG2-positive cells significantly decreased with tumor grade (mean expression level=4.6±0.7 in WHO grade II vs. 3.0±0.4 in glioblastoma WHO IV, p<0.0001) and correlated with better patient survival when applying univariate Kaplan Meier analysis. However, this could not be confirmed in a multivariate survival analysis including known prognostic factors such as patient age at diagnosis, Karnofsky Performance Score, WHO grade and extent of tumor resection. Further, no significant differences were seen when comparing expression of NG2 in primary glioblastomas (4.5±2.0) and their recurrent tumors (3.5±2.1). Furthermore, low grade gliomas did not vary in NG2 expression (4.4±1.4) compared to their own malignant relapse (4.3±0.7).

Conclusions: Although NG2 was originally described as an antigen associated with an immature phenotype, our findings clearly show an inverse correlation of NG2 expression with WHO-grade and no influence on the outcome of the respective patients.