title: Plasma miR-26a as a Diagnostic Biomarker Regulates Cytokine Expression in Systemic Juvenile Idiopathic Arthritis.
abstract: We sought to identify specific microRNA (miRNA) for systemic juvenile idiopathic arthritis (sJIA) and to determine the involvement of these miRNA in regulating the expression of cytokines.
  
  
  
  Microarray profiling was performed to identify differentially expressed miRNA in sJIA plasma. Levels of candidate miRNA and mRNA were assessed by real-time PCR, and cytokines were measured by ELISA. Dual-luciferase reporter assay was used to validate the direct interaction between miR-26a and interleukin 6 (IL-6).
  
  
  
  Forty-eight miRNA were differentially expressed in the plasma of patients with sJIA compared with healthy controls (HC). Five miRNA were selected for further validation. The expression level of miR-26a was exclusively elevated in the plasma of patients with sJIA as compared with 4 rheumatic diseases and 2 subtypes of JIA (oligoarticular and polyarticular). The levels of IL-6, IL-1β, and tumor necrosis factor-α in the plasma of patients with sJIA were increased, and only IL-6 presented a positive correlation with miR-26a (r = 0.539, p < 0.0001). After stimulation with IL-6, miR-26a expression was upregulated in THP-1 cells, while the supernatant level of IL-6 was downregulated by transfection of miR-26a mimics. Consistently, direct target relationship between miR-26a and IL-6 was confirmed.
  
  
  
  This study demonstrates that miR-26a is expressed specifically and highly in sJIA plasma and suggests that miR-26a may regulate the levels of cytokines in sJIA. Our findings highlight miR-26a as a potential biomarker for the diagnosis as well as differential diagnosis of sJIA.
authors.affiliation: From the Department of Molecular Immunology, and the Department of Immunology and Rheumatology, Capital Institute of Pediatrics, Beijing, China.J. Sun*, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Feng*, PhD, Department of Molecular Immunology, Capital Institute of Pediatrics; F. Wu, MD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; X. Ma, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; J. Lu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Kang, PhD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; Z. Liu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics.
authors.forename: Juan
authors.initials: J
authors.lastname: Sun
authors.affiliation: From the Department of Molecular Immunology, and the Department of Immunology and Rheumatology, Capital Institute of Pediatrics, Beijing, China.J. Sun*, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Feng*, PhD, Department of Molecular Immunology, Capital Institute of Pediatrics; F. Wu, MD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; X. Ma, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; J. Lu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Kang, PhD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; Z. Liu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics.
authors.forename: Miao
authors.initials: M
authors.lastname: Feng
authors.affiliation: From the Department of Molecular Immunology, and the Department of Immunology and Rheumatology, Capital Institute of Pediatrics, Beijing, China.J. Sun*, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Feng*, PhD, Department of Molecular Immunology, Capital Institute of Pediatrics; F. Wu, MD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; X. Ma, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; J. Lu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Kang, PhD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; Z. Liu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics.
authors.forename: Fengqi
authors.initials: F
authors.lastname: Wu
authors.affiliation: From the Department of Molecular Immunology, and the Department of Immunology and Rheumatology, Capital Institute of Pediatrics, Beijing, China.J. Sun*, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Feng*, PhD, Department of Molecular Immunology, Capital Institute of Pediatrics; F. Wu, MD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; X. Ma, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; J. Lu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Kang, PhD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; Z. Liu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Ma
authors.affiliation: From the Department of Molecular Immunology, and the Department of Immunology and Rheumatology, Capital Institute of Pediatrics, Beijing, China.J. Sun*, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Feng*, PhD, Department of Molecular Immunology, Capital Institute of Pediatrics; F. Wu, MD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; X. Ma, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; J. Lu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Kang, PhD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; Z. Liu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics.
authors.forename: Jie
authors.initials: J
authors.lastname: Lu
authors.affiliation: From the Department of Molecular Immunology, and the Department of Immunology and Rheumatology, Capital Institute of Pediatrics, Beijing, China.J. Sun*, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Feng*, PhD, Department of Molecular Immunology, Capital Institute of Pediatrics; F. Wu, MD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; X. Ma, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; J. Lu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Kang, PhD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; Z. Liu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics.
authors.forename: Min
authors.initials: M
authors.lastname: Kang
authors.affiliation: From the Department of Molecular Immunology, and the Department of Immunology and Rheumatology, Capital Institute of Pediatrics, Beijing, China.J. Sun*, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Feng*, PhD, Department of Molecular Immunology, Capital Institute of Pediatrics; F. Wu, MD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; X. Ma, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; J. Lu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics; M. Kang, PhD, Department of Immunology and Rheumatology, Capital Institute of Pediatrics; Z. Liu, MD, Department of Molecular Immunology, Capital Institute of Pediatrics. 851439273@qq.com.
authors.forename: Zhewei
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D001171:Arthritis, Juvenile / Q000097:blood / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000097:blood*
chemical_list: D015415:Biomarkers; D016207:Cytokines; D035683:MicroRNAs; C528163:MIRN26 microRNA, human
keywords: BIOMARKER; CYTOKINES; MIR-26A; SYSTEMIC JUVENILE IDIOPATHIC ARTHRITIS