title: Overexpression of microRNA-155 suppresses chemokine expression induced by Interleukin-13 in BEAS-2B human bronchial epithelial cells.
abstract: BACKGROUND
  MicroRNAs are non-coding small RNAs that regulate expression of target genes by binding to 3' untranslated regions. In this study, we used bronchial epithelial cells to investigate in vitro the role of the microRNA miR-155 in the expression of chemokines associated with airway inflammation. miR-155 has previously been reported to regulate allergic inflammation.
  
  
  METHODS
  BEAS-2B bronchial epithelial cells were cultured and transfected with mimic or inhibitor oligonucleotides to overexpress or downregulate miR-155, as confirmed by real-time PCR. Cells were then stimulated with tumor necrosis factor-alpha, interleukin-13 (IL-13), and a double stranded RNA that binds Toll-like receptor 3. Expression and secretion of the chemokines CCL5, CCL11, CCL26, CXCL8, and CXCL10 were then quantified by real-time PCR and ELISA, respectively. Phosphorylation of signal transducer and activator of transcription 6 (STAT6), a target of the IL-13 receptor, was analyzed by ELISA.
  
  
  RESULTS
  miR-155 overexpression significantly suppressed IL-13-induced secretion of CCL11 and CCL26. These effects were specific, and were not observed for other chemokines, nor in cells with downregulated miR-155. miR-155 overexpression also suppressed CCL11 and CCL26 mRNA, but did not affect expression of the IL-13 receptor or phosphorylation of STAT6.
  
  
  CONCLUSIONS
  miR-155 specifically inhibits IL-13-induced expression of eosinophilic chemokines CCL11 and CCL26 in bronchial epithelial cells, even though the 3'-untranslated region of these genes do not contain a consensus binding site for miR-155.
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan. Electronic address: smatsuku@med.showa-u.ac.jp.
authors: Satoshi
authors: S
authors: Matsukura
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Yuki
authors: Y
authors: Osakabe
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Ayaka
authors: A
authors: Sekiguchi
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Daisuke
authors: D
authors: Inoue
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Yusuke
authors: Y
authors: Kakiuchi
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Toshitaka
authors: T
authors: Funaki
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Yohei
authors: Y
authors: Yamazaki
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Hiromi
authors: H
authors: Takayasu
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Hidetsugu
authors: H
authors: Tateno
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Eisuke
authors: E
authors: Kato
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Aya
authors: A
authors: Wakabayashi
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Makoto
authors: M
authors: Hayashi
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan; Respiratory Disease Center, Showa University Northern Yokohama Hospital, Kanagawa, Japan.
authors: Gen
authors: G
authors: Ishii
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Fumihiro
authors: F
authors: Yamaguchi
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Yutaka
authors: Y
authors: Tsuchiya
authors: Respiratory Disease Center, Showa University Northern Yokohama Hospital, Kanagawa, Japan.
authors: Keita
authors: K
authors: Kasahara
authors: Department of Internal Medicine, Division of Allergy and Respiratory Medicine, Showa University School of Medicine, Tokyo, Japan.
authors: Hironori
authors: H
authors: Sagara
authors: Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
authors: Fumio
authors: F
authors: Kokubu
mesh_terms: D001980:Bronchi; D002460:Cell Line; D018925:Chemokines / Q000235:genetics* / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D018793:Interleukin-13 / Q000494:pharmacology*; D035683:MicroRNAs / Q000235:genetics*; D010766:Phosphorylation; D020871:RNA Stability; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020545:Respiratory Mucosa / Q000378:metabolism; D050800:STAT6 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D018925:Chemokines; D018793:Interleukin-13; C524942:MIRN155 microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; D050800:STAT6 Transcription Factor
keywords: Asthma; Bronchial epithelial cells; CCL11; CCL26; miR-155