IRF9 and glioblastoma: The largest cluster, containing genes almost exclusively up-regulated in GBMO, was surprisingly enriched for immune signaling genes associated with interferon pathways (IFITM1, STAT1, OAS1, IRF9, IRF3, IRF1, HLA, NFKB1), cytokines (IL6), as well as hallmark processes of cancer (IDH1) and (MEF/ELF4), a transcription factor associated with stemness in GBM (Fig. 2a, blue columns).