Background: Glioblastoma multiforme (GBM) is a primary brain tumour with a very poor prognosis despite aggressive multi-modality treatment. This pre-clinical experimental study focuses on the effect of irradiation on three-dimensional glioma biopsy spheroids in vitro using an outgrowth assay to evaluate cell survival and migrational capacity of the glioma cells.
Materials and methods: Tumour tissue of 16 patients with high-grade glioma and two GBM cell lines were used for spheroid preparation. Outgrowth and cell density were the parameters chosen to evaluate cell cytotoxicity and migrational capacity after irradiation (20 Gy and 4 x 5 Gy).
Results: Radiation inhibited outgrowth of cell line spheroids, but not of the biopsy spheroids. All biopsy and cell line spheroids showed a significantly lower cell number (95 vs. 24 cells/0.25 mm2) in the outgrowth area after irradiation.
Conclusion: Irradiation has a cytotoxic effect in GBM biopsy spheroids but it hardly affects cell migration. No correlation was found between patient survival and cell migration nor with cytotoxicity.