Differences in transcriptomic profiles between glioblastoma-initiating cells (GICs) and non-GICs upon radiation treatment

GICs are considered a major determinant in glioblastoma treatment failure, as they exhibit a marked resistance to radiotherapy. However, the exact mechanisms that confer this radioresistance to GICs are still not fully understood. We have performed a microarray analysis after radiation treatment of GICs and non-GICs cultures with the aim of identifying genes, pathways and transcription factors differentially expressed between these two cellular compartments. GICs and non-GICs cultures derived from a glioblastoma patient named as PG35s and PG35, respectively, were irradiated with fractionated radiotherapy at a dose of 2Gy/day up to 8Gy. After recovery, GICs once irradiated were exposed to a second cycle of radiation. Then, total RNA was extracted from both, controls and irradiated conditions. Three independent experiments were performed using different batches for each sample.