gms | German Medical Science

63. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie (JNS)

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

13. - 16. Juni 2012, Leipzig

Genes regulated by short-term versus long-term hypoxia in glioblastoma stem cell lines

Meeting Abstract

  • A. Kathagen - Klinik und Poliklinik für Neurochirurgie, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Deutschland
  • A. Schulte - Klinik und Poliklinik für Neurochirurgie, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Deutschland
  • H. Günther - Klinik und Poliklinik für Neurochirurgie, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Deutschland
  • H. Phillips - Klinik für Tumorbiologie und Angiogenese, Genentech, Inc., South San Franscisco, United States
  • M. Westphal - Klinik und Poliklinik für Neurochirurgie, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Deutschland
  • K. Lamszus - Klinik und Poliklinik für Neurochirurgie, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Deutschland

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 63. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie (JNS). Leipzig, 13.-16.06.2012. Düsseldorf: German Medical Science GMS Publishing House; 2012. DocFR.07.01

DOI: 10.3205/12dgnc214, URN: urn:nbn:de:0183-12dgnc2146

Veröffentlicht: 4. Juni 2012

© 2012 Kathagen 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: Tumor stem cells (TSC) are believed to be responsible for continuous glioma growth and progression, and to reside in hypoxic tumor niches. We aimed to identify genes regulated by short- and long-term hypoxia in glioma stem cell (GS) lines and determine their responsibilty for the maintenance of the TSC phenotype.

Methods: GS cell lines were established from 4 different glioblastomas either under normoxia (21% O2, GSN lines) or hypoxia (1% O2, GSH lines). Subsequently, GSN lines were exposed to short-term (48 hrs) hypoxia, and GSH lines to short-term normoxia. Gene expression was profiled using Affymetrix arrays. Validations were performed on cell lines and tumor tissues using qRT-PCR, Western blot, immunohistochemical and immunocytochemical analyses. The influence of target downregulation on proliferation and migration using modified Boyden chamber assays was determined.

Results: We identified distinct sets of genes induced by short-term hypoxia as opposed to long-term hypoxia. Functional gene annotation analyses showed that genes induced by short-term hypoxia were related to metabolic adaption processes, whereas genes upregulated under long-term hypoxia were predominantly associated with neural development. Transcriptional induction of selected genes was confirmed by qRT-PCR analyses, showing for example a significant increase in the expression of Aldolase C under short-term hypoxia (mean factor of 4.66 in GS-11) compared to normoxic controls. Upregulation of these genes was confirmed at the protein level. Time course experiments point towards peak induction of all genes analysed after 16–24 hrs. Immunofluorescence staining of the neuropheres, and immunostaining of human tumor tissue, identified characteristic localisation patterns. ShRNA-mediated downregulation of Aldolase C resulted in increased cell proliferation under normoxia and hypoxia and in reduced capacity of migration under hypoxia compared to control cells.

Conclusions: Distinct sets of genes are induced by short-term versus long-term hypoxia in GS cells. Their potential influence on the TSC phenotype maintenance warrants their evaluation as selective drug targets to elimate TSC in glioblastomas.