Differential expression of microRNAs in peripheral blood mononuclear cells identifies autophagy and TGF-beta related signatures aberrantly expressed in inflammatory bowel disease.
J Crohns Colitis. 2018 Feb 06;:
Authors: Mohammadi A, Kelly OB, Filice M, Kabakchiev B, Smith MI, Silverberg MS
Background and Aims: MicroRNAs (miRNAs) have emerged as important regulators in inflammatory bowel disease (IBD). This study investigated differential expression of miRNAs across clinical phenotypes in a well-characterized cohort of IBD patients and healthy controls (HCs).
Methods: A cohort with Crohn’s disease (CD), ulcerative colitis (UC), and HC was prospectively accrued. Total RNA was extracted from peripheral blood mononuclear cells for all subjects. MiRNA expression was measured using NanoString Technologies. The subjects were stratified according to disease activity and location. Statistical significance was assessed per miRNA across outcomes and corrected for multiple testing. MiRNA regulation of transcription of important results was confirmed in vitro by dual luciferase reporter assay and autophagy function was evaluated using immunofluorescence imaging of LC3 puncta in HeLa cells.
Results: 120 subjects were enrolled. 74 miRNAs were differentially expressed across CD, UC and HC. Comparing quiescent CD (CDq) with HC we found 10 miRNAs upregulated in CDq. When comparing colonic CD (CCD) to UC, 7 miRNAs were upregulated in CCD. The most differentially expressed miRNA in CCD versus UC was miR-874-3p, and we showed its possible utility as a biomarker of differential diagnosis. We showed miR-874-3p targets ATG16L1 and reduces its expression in vitro. We observed a miR-874-3p mimic dysregulates autophagy by a reduction of LC3 in vitro.
Conclusions: We identified unique miRNA signatures expressed in distinct IBD phenotypes. These associations highlight pathways dysregulated by aberrant miRNA expression, revealing possible mechanisms underlying the pathophysiology of IBD, but also suggest a cluster of miRNAs as readily accessible biomarkers to aid in differential diagnosis.
PMID: 29420705 [PubMed – as supplied by publisher]