Consistent with a prior study that TCF4/β-catenin contributes to GBM development32, TCF4 had higher expression in PN compared with MES spheres (Fig. 3b), and displayed a positive correlation with the expression of miR-125b and miR-20b in 12 PN and MES spheres (Fig. 3c). This evidence concerns the gene TCF4 and glioblastoma.