Fig. 5. ZEB1 is involved in radioresistance mediated by α6-integrin overexpression in GBM.

a-e Cells derived from two GBM biopsy specimens (GC1 and GC2) were transfected with an α6-integrin siRNA (si-α6), a ZEB1 siRNA (si-ZEB1 (1) and si-ZEB1 (2)), or a scramble control (si-Scr). a, c Different proteins, under basal conditions, were analyzed by western blot. Images are representative of three independent experiments. Actin was used as a loading control. d, e Cells were analyzed in 3D clonogenic assays as described in Materials and methods section. f GC1 and GC2 cells were pre-treated or not with 10 µM of the MEK inhibitor U-0126 and ZEB1 mRNA expression was analyzed by real-time PCR. Quantifications of three experiments are presented as means ± SD. ***p < 0.001; **0.001 < p < 0.01; *0.01 < p < 0.05