gms | German Medical Science

55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e. V. (DGNC)
1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

25. bis 28.04.2004, Köln

Phototherapy of C6 glioma spheroids with 5-aminolevulinic acid using a novel technique for the evaluation of phototherapy effects

Phototherapie von C6-Spheroiden nach Gabe von 5-Aminolävulinsäure unter Verwendung einer neuartigen Technik zur Wirkungserfassung der Phototherapie

Meeting Abstract

  • corresponding author Walter Stummer - Department of Neurosurgery, Heinrich-Heine University, Düsseldorf
  • P. Zelenkov - Department of Neurosurgery, Ludwig-Maximilians University, Munich; I. M. Sechenov Moscow Medical Academy, Moscow /RUS
  • R. Baumgartner - Laser Research Laboratory, Ludwig-Maximilians University, Munich
  • S. Stocker - Laser Research Laboratory, Ludwig-Maximilians University, Munich
  • R. Sroka - Laser Research Laboratory, Ludwig-Maximilians University, Munich
  • R. Meier - Laser Research Laboratory, Ludwig-Maximilians University, Munich
  • K. Bise - Institute for Neuropathology, Ludwig-Maximilians University, Munich
  • M. Heide - Department of Neurosurgery and Laser Research Laboratory , Ludwig-Maximilians University, Munich

Deutsche Gesellschaft für Neurochirurgie. Ungarische Gesellschaft für Neurochirurgie. 55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), 1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie. Köln, 25.-28.04.2004. Düsseldorf, Köln: German Medical Science; 2004. DocMO.12.09

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/dgnc2004/04dgnc0124.shtml

Veröffentlicht: 23. April 2004

© 2004 Stummer 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 vervielf&aauml;ltigt, verbreitet und &oauml;ffentlich zug&aauml;nglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Objective

5-ALA-mediated phototherapy (ALA-PT) is under investigation as an adjunct for malignant glioma therapy. However, little is known on the variables involved in this modality. For further insight, we have used a three-dimensional cell culture - the C6 glioma spheroid model, to study the effects of ALA-PT.

Methods

Spheroids were incubated for 4 hours in 100 mcg/ml 5-ALA in 5% CO2 or 100% O2 and where then irradiated using a 633 nm diode laser with 40 mW/cm2 to a total dose of 25 J/cm2. Necrotic, apoptotic and vital cells were assessed using a newly developed method of fluorescence staining with Annexin-FITC, Propidium Jodid and Hoechst 33342 (Oncogene, Germany). Fluorescence images were acquired by confocal laser scanning microscopy and fluorescence microscopy. In order to confirm the reliability of the new method, we performed hematoxylin-eosin staining and TUNEL assays (Oncogene, Germany) on cryosections. Cell death was estimated in the first hour after ALA-PT and one week later. Spheroid's growth kinetics was observed during 8 days following ALA-PT.

Results

ALA-PT after incubation in 5% CO2 provides 70% cell death and growth delay in spheroids of 400 mcm diameter. However, 100% cell death and a complete stop of growth occurs in smaller spheroids (300 mcm). Incubation in 100% O2 with following ALA-PT resulted in 100% cell death and a complete stop of growth regardless of spheroid size. In all cases, cell death after ALA-PT was established to be an apoptosis-resembling process. With 70% cell death, vital cells were restricted to the centre of spheroids. Cell death in control groups, i.e. "laser only", "5-ALA only" and "intact group" did not exceed 10%, and permanent growth was recorded.

Conclusions

ALA-PT of experimental glioma results in rapid and significant cell death, which depends on O2 concentration and spheroid size. We established a modern, easy and time-saving method for estimation of PT effects, that can be used experimentally and will be tested clinically.