Comprehensive identification of edited miRNAs in glioblastoma and glioblastoma cell lines

A-to-I editing modifies RNA transcripts from their genomic blueprint. A prerequisite for this process is a double-stranded RNA (dsRNA) structure. Such dsRNAs are formed as part of the micro-RNA (miRNA) maturation process, and it is therefore expected that miRNAs are affected by A-to-I editing. Editing of miRNAs has the potential to add another layer of complexity to gene regulation pathways, especially if editing occurs within the miRNA recognition site, and recent studies have suggested its potential as a biomarker for cancer prognosis and therapy. Utilizing a next-generation sequencing approach supplemented by an extensive bioinformatic analysis, we were able to systematically identify A-to-I editing events in mature miRNAs derived from glioblastoma tissues and cell lines. The DREAM algorithm identified many of the known editing sites in mature miRNAs, and revealed additional novel sites, some of which are in the recognition sites of the miRNAs.