EZH2 and glioblastoma: Additionally, compared to normal human brain specimens, surgical GBM specimens showed a remarkable upregulation of EZH2 and Notch1 and, as previously reported, Zheng et al. [85] observed that Notch1 was significantly downregulated in knockdown EZH2 GBM cells, thus underlining the role of melatonin in the inhibition of the EZH2–Notch1 signaling axis.