title: Upregulated microRNA-155 expression in peripheral blood mononuclear cells and fibroblast-like synoviocytes in rheumatoid arthritis.
abstract: OBJECTIVE
  This study was to screen for the miRNAs differently expressed in peripheral blood mononuclear cells (PBMC) of RA, to further identify the expression of miR-155 in RA PBMC and fibroblast-like synoviocytes (FLS), and to evaluate the function of miR-155 in RA-FLS.
  
  
  METHODS
  Microarray was used to screen for differentially expressed miRNAs in RA PBMC. miR-155 expression in PBMC and FLS of RA were identified by real-time PCR. Enforced overexpression and downexpression of miR-155 were used to investigate the function of miR-155 in RA-FLS. Expression of IKBKE which was previously identified as the actual target of miR-155 was examined by Western blot and real-time PCR in RA-FLS.
  
  
  RESULTS
  miR-155 levels were increased in both PBMC and FLS of RA and could be induced by TNF- α . Upregulation of miR-155 decreased MMP-3 levels and suppressed proliferation and invasion of RA-FLS. Inverse relationship between the expressions of miR-155 and the MMPs production-related protein IKBKE was found.
  
  
  CONCLUSIONS
  An inflammatory milieu may alter miRNA expression profiles in rheumatoid arthritis. miR-155 is upregulated in RA-FLS, and it may be a protective factor against the inflammatory effect in part by attenuating expression of IKBKE.
authors.affiliation: Department of Rheumatology & Immunology, Peking University People's Hospital, 11 Xizhimen South Street, Beijing 100044, China ; Department of Rheumatology & Immunology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu 610072, China.
authors.forename: Li
authors.initials: L
authors.lastname: Long
authors.forename: Ping
authors.initials: P
authors.lastname: Yu
authors.forename: Yanying
authors.initials: Y
authors.lastname: Liu
authors.forename: Shiyao
authors.initials: S
authors.lastname: Wang
authors.forename: Ru
authors.initials: R
authors.lastname: Li
authors.forename: Jinxia
authors.initials: J
authors.lastname: Shi
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Zhang
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Sun
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.forename: Liufu
authors.initials: L
authors.lastname: Cui
authors.forename: Zhanguo
authors.initials: Z
authors.lastname: Li
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000235:genetics; D001172:Arthritis, Rheumatoid / Q000235:genetics*; D016022:Case-Control Studies; D049109:Cell Proliferation; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D051550:I-kappa B Kinase / Q000235:genetics / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D019278:Matrix Metalloproteinase 3 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D015203:Reproducibility of Results; D013583:Synovial Membrane / Q000166:cytology*; D016212:Transforming Growth Factor beta / Q000096:biosynthesis; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000494:pharmacology; D015854:Up-Regulation; D055815:Young Adult
chemical_list: C524942:MIRN155 microRNA, human; D035683:MicroRNAs; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D051550:I-kappa B Kinase; C496565:IKBKE protein, human; D019278:Matrix Metalloproteinase 3; D020780:Matrix Metalloproteinase 9