title: Circulating microRNAs as noninvasive diagnostic biomarkers of liver disease in children with cystic fibrosis.
abstract: OBJECTIVE
  Cystic fibrosis liver disease (CFLD), resulting from progressive hepatobiliary fibrosis, causes significant morbidity and mortality in up to 20% of children with cystic fibrosis (CF). Both pathogenesis and early detection of CFLD are elusive. Current diagnostic procedures to detect early CFLD and stage fibrosis severity are inadequate. Recent studies highlight a role for microRNAs (miRNAs) in the pathogenesis of many diseases and have suggested that serum miRNAs could be used as diagnostic biomarkers.
  
  
  METHODS
  We profiled circulating serum miRNA levels in patients with CFLD (n = 52), patients with CF without liver disease (CFnoLD, n = 30), and non-CF pediatric controls (n = 20). Extracted RNA was subjected to polymerase chain reaction (PCR) array of 84 miRNAs detectable in human serum. Seven candidate miRNAs identified were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR), normalizing data to geNorm-determined stable reference genes, miR-19b and miR-93.
  
  
  RESULTS
  miR-122 was significantly elevated in patients with CFLD versus patients with CFnoLD and controls (P < 0.0001). miR-25 (P = 0.0011) and miR-21 (P = 0.0133) were elevated in patients with CFnoLD versus patients with CFLD and controls. CFLD was discriminated by both miR-122 (area under the curve [AUC] 0.71, P = 0.002) and miR-25 (AUC 0.65, P = 0.026). Logistic regression combining 3 miRNAs (-122, -25, -21) was greatly predictive of detecting CFLD (AUC 0.78, P < 0.0001). A combination of 6 miRNAs (-122, -21, -25, -210, -148a, -19a) distinguished F0 from F3-F4 fibrosis (AUC 0.73, P = 0.04), and miR-210 combined with miR-22 distinguished F0 fibrosis from any fibrosis, that is, F1-F4 (AUC 0.72, P = 0.02).
  
  
  CONCLUSIONS
  These data provide the first evidence of changes to circulating miRNA levels in CF, suggesting that serum-based miRNA analysis may complement and extend current CFLD screening strategies with potential to predict early hepatic fibrosis.
authors.affiliation: *Hepatic Fibrosis Group, QIMR Berghofer Medical Research Institute †Department of Gastroenterology, Royal Children's Hospital, Brisbane, Australia ‡Department of Pediatrics, Baylor College of Medicine, Houston, TX, Brisbane, Australia.
authors.forename: Naomi L
authors.initials: NL
authors.lastname: Cook
authors.forename: Tamara N
authors.initials: TN
authors.lastname: Pereira
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Lewindon
authors.forename: Ross W
authors.initials: RW
authors.lastname: Shepherd
authors.forename: Grant A
authors.initials: GA
authors.lastname: Ramm
mesh_terms: D000293:Adolescent; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000150:complications*; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000097:blood* / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D035683:MicroRNAs / Q000097:blood*; D020411:Oligonucleotide Array Sequence Analysis; D011237:Predictive Value of Tests; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; C531907:MIRN122 microRNA, human; C550570:MIRN148 microRNA, human; C549214:MIRN19A microRNA, human; C524940:MIRN21 microRNA, human; C543800:MIRN210 microRNA, human; C548375:MIRN22 microRNA, human; C543351:MIRN25 microRNA, human; D035683:MicroRNAs