To further strengthen these results, analyzing an independent dataset from GEO database, we verified that short-term exposure (96 h) of cultured glioblastoma cell line (GLI56) to 5-aza-2′-deoxycytidine (5-aza-dC) [5 μM], a global DNA demethylating agent, induced a substantial increase in the GPX7 expression (Supplementary Fig. S6), thus strongly suggesting that upregulation of GPX7 is tightly regulated by DNA methylation. This evidence concerns the gene GPX7 and glioblastoma.