POU5F1 and glioblastoma: Moreover, we and others previously showed that this IAP is involvedin GBM radioresistance,32, 46 is increased by IR in GBM cells,46, 49 is upregulated in GSCcompared with differentiated GBM cells,49is associated with faster GBM recurrence49and is overexpressed in GBM recurrence tumor samples compared with newly diagnosedones.49 In addition, survivin wasalso shown to be tightly associated with different stem-promoting pathways inCSC/NSC, notably SonicHH/Gli1,48Notch,59 Oct4/Stat360 and Sox2.61 In consequence, we investigated its role in the IR-induced GBMcell dedifferentiation.