ARL4C and ependymoma: ARL4C transcription is significantly upregulated (p-value: 1.63e−16) in PFA tumors compared to other ependymoma groups (Supplementary Fig. 7e) and is highly correlated with the activity of the enhancer elements that physically interact with the ARL4C gene locus in PFA but not in ZFTA tumors (Fig. 4g).