Global gene expression profiles in GSCs from primary and recurrent gliomas. (A) Global gene expression was assayed using the Affymetrix 133 plus 2.0 microarray. The Notch signaling-related and Twist1 genes were notably upregulated. (B–E) Notch signaling-related genes and Twist1 had significant differences in mRNA levels between primary and recurrent GSC lines. Data are presented as the mean ± SD. *: P < 0.05 and **: P < 0.01.