Cygb protein expression in human GBM cells. Cygb expression was assessed by Western blot analyses after exposure to hypoxia (0.6% O2) for 0, 6, 24 and 48 h (n = 4). The integrated intensities of Cygb and α- tubulin (control) bands were determined and expressed in arbitrary units (AU), and representative blots are shown. (A) M006x: (B) M006xLo; (C) M010B; (D) M059J; (E) U87T. *p < 0.05; **p < 0.01; ***p < 0.001 (ANOVA).