title: Differentiation of human dental stem cells reveals a role for microRNA-218.
abstract: BACKGROUND
  Regeneration of lost periodontium is the ultimate goal of periodontal therapy. Advances in tissue engineering have demonstrated the multilineage potential and plasticity of adult stem cells located in periodontal apparatus. However, it remains unclear how epigenetic mechanisms controlling signals determine tissue specification and cell lineage decisions. To date, no data are available on micro-RNA (miRNA) activity behind human-derived dental stem cells (DSCs).
  
  
  METHODS
  In this study, we isolated periodontal ligament stem cells, dental pulp stem cells and gingival stem cells from extracted third molars; human bone marrow stem cells were used as a positive control. The expression of OCT4A and NANOG was confirmed in these undifferentiated cells. All cells were cultured under osteogenic inductive conditions and RUNX2 expression was analyzed as a marker of mineralized tissue differentiation. The miRNA expression profile was obtained at baseline and after osteogenic induction in all cell types.
  
  
  RESULTS
  The expression of RUNX2 demonstrated successful osteogenic induction of all cell types, which was confirmed by alizarin red stain. The analysis of 765 miRNAs demonstrated a shift in miRNA expression that occurred in all four stem cell types, including a decrease in hsa-mir-218 across all differentiated cell populations. Hsa-mir-218 targets RUNX2 and decreases RUNX2 expression in undifferentiated human DSCs. DSC mineralized tissue type differentiation is associated with a decrease in hsa-mir-218 expression.
  
  
  CONCLUSIONS
  These data reveal a miRNA-regulated pathway for the differentiation of human DSCs and a select network of human miRNAs that control DSC osteogenic differentiation.
authors.affiliation: Dental School, The University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: I
authors.initials: I
authors.lastname: Gay
authors.forename: A
authors.initials: A
authors.lastname: Cavender
authors.forename: D
authors.initials: D
authors.lastname: Peto
authors.forename: Z
authors.initials: Z
authors.lastname: Sun
authors.forename: A
authors.initials: A
authors.lastname: Speer
authors.forename: H
authors.initials: H
authors.lastname: Cao
authors.forename: B A
authors.initials: BA
authors.lastname: Amendt
mesh_terms: D053687:Adult Stem Cells / Q000502:physiology*; D000880:Anthraquinones; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000235:genetics; D002469:Cell Separation / Q000379:methods; D004396:Coloring Agents; D050659:Core Binding Factor Alpha 1 Subunit / Q000032:analysis; D003782:Dental Pulp / Q000166:cytology*; D005434:Flow Cytometry / Q000379:methods; D018390:Gene Targeting / Q000379:methods; D005881:Gingiva / Q000166:cytology; D018398:Homeodomain Proteins / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D059630:Mesenchymal Stem Cells / Q000502:physiology; D035683:MicroRNAs / Q000032:analysis / Q000502:physiology*; D000071317:Nanog Homeobox Protein; D050814:Octamer Transcription Factor-3 / Q000032:analysis; D010012:Osteogenesis / Q000502:physiology; D010513:Periodontal Ligament / Q000166:cytology; D010519:Periodontium / Q000166:cytology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000880:Anthraquinones; D004396:Coloring Agents; D050659:Core Binding Factor Alpha 1 Subunit; D018398:Homeodomain Proteins; C547471:MIRN218 microRNA, human; D035683:MicroRNAs; C486780:NANOG protein, human; D000071317:Nanog Homeobox Protein; D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human; C493709:RUNX2 protein, human; C010078:alizarin
keywords: RNA induced silencing complex; RUNX2; cell differentiation; messenger RNA; osteogenesis; stem cells