title: GnRH regulates trophoblast invasion via RUNX2-mediated MMP2/9 expression.
abstract: OBJECTIVE
  We hypothesized that Runt-related transcription factor 2 (RUNX2), matrix metalloproteinase (MMP)2 and MMP9 are involved in basal and gonadotrophin-releasing hormone (GnRH)-induced human extravillous trophoblast (EVT) cell invasion.
  
  
  RESULTS
  Our finding indicates that GnRH-induced RUNX2 expression enhances the invasive capacity of EVT cells by modulating the expression of MMP2 and MMP9.
  
  
  BACKGROUND
  GnRH is expressed in first-trimester placenta and exerts pro-invasive effects on EVT cells in vitro. RUNX2 regulates MMP2 and MMP9 expression and is often associated with invasive phenotypes.
  
  
  METHODS
  First-trimester human placenta (n = 9) was obtained from women undergoing elective termination of pregnancy. The localization of RUNX2, MMP2 and MMP9 in first-trimester human placenta was examined by immunohistochemistry. Primary or immortalized (HTR-8/SVneo) EVT cells were treated alone or in combination with GnRH, GnRH antagonist Antide, MAPK kinase inhibitor PD98095, phosphatidylinositol 3-kinase inhibitor LY294002, MMP2/9 inhibitor or small interfering RNAs (siRNAs) targeting RUNX2, MMP2 and/or MMP9. Protein and mRNA levels were measured by western blot and RT-PCR, respectively. Cell invasiveness was evaluated by transwell Matrigel or collagen I invasion assays.
  
  
  RESULTS
  RUNX2, MMP2 and MMP9 were detected in the cell column regions of human first-trimester placental villi. GnRH treatment increased RUNX2 mRNA and protein levels in HTR-8/SVneo cells and primary EVTs, and these effects were attenuated by co-treatment with Antide, PD98095 or LY294002. Down-regulation of RUNX2 by siRNA reduced basal and GnRH-induced MMP2/9 expression and cell invasion. Moreover, pharmacological inhibition or siRNA-mediated knockdown of MMP2/9 reduced basal and GnRH-induced cell invasion.
  
  
  CONCLUSIONS
  The lack of an in vivo model is the major limitation of our in vitro study.
  
  
  CONCLUSIONS
  Our findings provide important insight into the functions of the GnRH - GnRH receptor system in early implantation and placentation.
  
  
  METHODS
  Not applicable.
  
  
  BACKGROUND
  This research was supported by Canadian Institutes of Health Research (Grant #143317) to P.C.K.L. The authors have nothing to disclose.
authors.affiliation: Department of Obstetrics & Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Bo
authors.initials: B
authors.lastname: Peng
authors.affiliation: Department of Obstetrics & Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Department of Obstetrics & Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Christian
authors.initials: C
authors.lastname: Klausen
authors.affiliation: State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P. R. China.
authors.forename: Liyang
authors.initials: L
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P. R. China.
authors.forename: Yan-Ling
authors.initials: YL
authors.lastname: Wang
authors.affiliation: Department of Obstetrics & Gynaecology, Child & Family Research Institute, University of British Columbia, Vancouver, BC, Canada peter.leung@ubc.ca.
authors.forename: Peter C K
authors.initials: PC
authors.lastname: Leung
mesh_terms: D000029:Abortion, Legal; D000328:Adult; D002461:Cell Line, Transformed; D002465:Cell Movement / Q000187:drug effects; D002824:Chorionic Villi / Q000378:metabolism; D002867:Chromones / Q000494:pharmacology; D050659:Core Binding Factor Alpha 1 Subunit / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D003656:Decidua / Q000166:cytology / Q000378:metabolism; D005260:Female; D005419:Flavonoids / Q000494:pharmacology; D005786:Gene Expression Regulation; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000235:genetics* / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000235:genetics* / Q000378:metabolism; D009025:Morpholines / Q000494:pharmacology; D009842:Oligopeptides / Q000494:pharmacology; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D061251:Primary Cell Culture; D012333:RNA, Messenger / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014327:Trophoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
chemical_list: D002867:Chromones; D050659:Core Binding Factor Alpha 1 Subunit; D005419:Flavonoids; D009025:Morpholines; D009842:Oligopeptides; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C493709:RUNX2 protein, human; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; D007987:Gonadotropin-Releasing Hormone; C057022:iturelix; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one
keywords: GnRH; MMP; RUNX2; invasion; trophoblast