gms | German Medical Science

65. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

11. - 14. Mai 2014, Dresden

Analysis of the effect of 1p/19q co-deletions in WHO grade-II oligodendrogliomas

Meeting Abstract

  • Özge Can - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey
  • Aylin Mutlu - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey
  • Sirin Yüksel - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey
  • Yavuz Oktay - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey
  • Cemaliye Akyerli - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey
  • Paolo Nanni - Functional Genomics Center Zurich, UZH/ETH Zurich, Zurich, Switzerland
  • Nathalie Selevsek - Functional Genomics Center Zurich, UZH/ETH Zurich, Zurich, Switzerland
  • Jonas Grossmann - Functional Genomics Center Zurich, UZH/ETH Zurich, Zurich, Switzerland
  • Aysel Özpinar - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey
  • Aydin Sav - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey
  • Cengiz Yakicier - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey
  • M. Necmettin Pamir - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey; Department of Neurosurgery, Acibadem University School of Medicine, Istanbul, Turkey
  • Koray Özduman - Acibadem University, Brain Tumor Research Center, Istanbul, Turkey; Department of Neurosurgery, Acibadem University School of Medicine, Istanbul, Turkey

Deutsche Gesellschaft für Neurochirurgie. 65. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC). Dresden, 11.-14.05.2014. Düsseldorf: German Medical Science GMS Publishing House; 2014. DocMO.07.06

doi: 10.3205/14dgnc034, urn:nbn:de:0183-14dgnc0348

Veröffentlicht: 13. Mai 2014

© 2014 Can 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: Among low-grade hemispheric gliomas, oligodendrogliomas have a relatively good prognosis. Oligodendrogliomas often carry 1p/19q co-deletions and the presence of this chromosomal change is associated with better prognosis and responsiveness to chemotherapy. Therefore the molecular biological changes associated with the 1p/19q co-deletion are of great interest. This study aims to compare the protein expression profile of 1p/19q co-deleted and non co-deleted oligodendrogliomas.

Method: 50 WHO grade-II oligodendrogliomas which were diagnosed by a single neuropathologist were analyzed for IDH1, IDH2, Olig-2, Ki67, EGFR, VEGF, pBRAF, c-myc, PTEN, p16Ink4A , TP53, MGMT methylation, 1p19q co-deletions, hTERT mutations were screened. 7 WHO grade-II oligodendrogliomas were included for the LC-MS/MS analysis. Tryptic digests of homogenized tissue extracts from 7 samples (5 patients with and 2 without 1p/19q codeletions) were analyzed by LC-MS/MS (LTQ-Orbitrap Velos ETD, Thermo Scientific) to analyze proteomic changes.

Results: After the analysis of the immunohistochemical and molecular biological markers in oligodendrogliomas, the most common pattern was that of oligodendrogliomas with (IDH mutation + 1p/19q co-deletions + hTERT promoter mutations + lost PTEN expression). In order to analyze the effects of 1p/19q co-deletions on the cellular proteome level more clearly, we have selected grade II oligodendrogliomas with or without 1p/19q co-deletions, which were all IDH mutant and lost PTEN protein expression. In the LC-MS/MS comparison of 5 codeleted oligodendrogliomas with 2 non-codeleted ones, 1601 proteins were identified with a false discovery rate of 0.2%. 116 proteins were found to be significantly regulated among the two groups (p<0.05), of which 14 of them have been associated with glioma previously. Granzyme A signaling (apoptosis and survival), cell adhesion and transcriptional silencing via heterochromatin protein 1 family were found to be the most significant pathways in the data set (p<0.0001). Correspondingly, the most important process networks for the proteomic data set were mRNA processing, chromatin modification, DNA damage/checkpoint (p<0.0001).

Conclusions: The presence of 1p/19q co-deletions are associated with different protein expression profiles in oligodendrogliomas.