title: MicroRNA-155 is involved in the remodelling of human-trophoblast-derived HTR-8/SVneo cells induced by lipopolysaccharides.
abstract: BACKGROUND
  A low dose injection of lipopolysaccharides (LPS) may induce pre-eclampsia-like symptoms in rats, and microRNA-155 (miR-155) is elevated in the placentas of patients with pre-eclampsia. Our goal was to investigate the association of miR-155 with pre-eclampsia and the pathways involved using human-trophoblast-derived cell line (HTR-8/SVneo) stimulated with LPS.
  
  
  METHODS
  We measured miR-155 in HTR-8/SVneo cells treated with LPS (25-800 ng/ml) using real-time PCR. Western blotting was used to study transcription factor activated protein 1 (AP-1) (JunB and FosB subunits) and nuclear factor (NF)-κB p65 in the HTR-8/SVneo cells and placentas from patients with pre-eclampsia. DNA precipitation assays and luciferase reporter analysis were used to evaluate the regulation of miR-155 by AP-1 and NF-κB. Cell migration was determined by scratch assay. Syncytialization of HTR-8/SVneo cells was analysed following transfection with miR-155.
  
  
  RESULTS
  miR-155 was increased together with AP-1 and NF-κB in HTR-8/SVneo cells incubated with low dose of LPS (≤100 ng/ml; P < 0.05 versus baseline). Both JunB/FosB and p65 were increased in placenta from women with severe pre-eclampsia versus a normal pregnancy, with elevated expression of miR-155 (P < 0.05). For specific DNA-binding sites upstream of BIC/miR-155 gene promoter, the AP-1 site was more important than the NF-κB site for increasing miR-155 in HTR-8/SVneo cells. The cells with enforced expression of miR-155 showed a reduced ability to migrate (P < 0.05) and an increased number of syncytiotrophoblast-like multinuclear cells (P < 0.05).
  
  
  CONCLUSIONS
  LPS may induce remodelling of the human-trophoblast-derived HTR-8/SVneo cells by increasing miR-155, acting in part through the AP-1 and NF-κB pathways.
authors.affiliation: Department of Obstetrics and Gynecology, Nanjing University Medical School, Nanjing, People's Republic of China.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Dai
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Diao
authors.forename: Haixiang
authors.initials: H
authors.lastname: Sun
authors.forename: Ruotian
authors.initials: R
authors.lastname: Li
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Qiu
authors.forename: Yali
authors.initials: Y
authors.lastname: Hu
mesh_terms: D015153:Blotting, Western; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D005260:Female; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology*; D035683:MicroRNAs / Q000378:metabolism / Q000502:physiology*; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D010920:Placenta / Q000378:metabolism*; D011225:Pre-Eclampsia / Q000235:genetics* / Q000378:metabolism; D011247:Pregnancy; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000378:metabolism; D014327:Trophoblasts / Q000187:drug effects / Q000378:metabolism / Q000502:physiology
chemical_list: D008070:Lipopolysaccharides; D035683:MicroRNAs; D016328:NF-kappa B; D018808:Transcription Factor AP-1