Finally, DOT1L inhibition induced H3K79me2 loss and consequent downregulation of glioblastoma multiforme fitness genes SOX2 and OLIG2. These data support involvement of this epi-enzyme in the regulation of GSC stemness in vivo and suggest potential beneficial effects of DOT1L inhibition for glioblastoma treatment (Macleod et al., 2019). Here, OLIG2 is linked to glioblastoma.