title: Comparative study of LHX8 expression between odontoma and dental tissue-derived stem cells.
abstract: BACKGROUND
  LHX8 (LIM-homeobox gene 8) is known as an important regulating factor in tooth morphogenesis. Odontoma is a mixed odontogenic tumor where epithelium and mesenchyme differentiated together, resulting in anomalous tooth structures. In this study, gene and protein expressions of LHX8 were analyzed in human odontoma-derived mesenchymal cells (HODC) compared to adult dental mesenchymal stem cells (aDSC), as well as morphological and histological characteristics of odontoma were analyzed.
  
  
  METHODS
  aDSCs were isolated from normal teeth, and HODCs were isolated from surgically removed odontoma mass. Morphological and histological evaluations were performed to compare between compound odontomas and normal premolars. RT-PCR and real-time PCR were performed to identify LHX8 mRNA expression in the HODCs and aDSCs. LHX8 protein expression levels were observed by immunoblotting and immunofluorescent staining.
  
  
  RESULTS
  The compound odontoma was composed of multiple tooth-like structures, which contained disorganized but recognizable enamel matrix, dentin, pulp, and cementum. LHX8 mRNA and LHX8 protein expressions were all higher in HODCs compared to those in aDSCs examined by RT-PCR, immunoblot, and immunofluorescent staining. Especially, real-time PCR showed 2.77-fold higher LHX8 expression in HODCs than in normal periodontal ligament stem cells (PDLSCs), while alveolar bone marrow stem cells (ABMSCs) expressed 0.12-fold LHX8 than PDLSCs.
  
  
  CONCLUSIONS
  Based on these observations, LHX8 might play an important role in odontoma formation. This is the first report regarding the comparison of LHX8 expression between HODC and normal aDSCs and its overexpression in human samples. The specific mechanism of LHX8 in odontoma morphogenesis awaits further study.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Dental Research Institute, Seoul, South Korea.
authors.forename: Ji-Youn
authors.initials: JY
authors.lastname: Kim
authors.forename: Soung Hoo
authors.initials: SH
authors.lastname: Jeon
authors.forename: Joo-Young
authors.initials: JY
authors.lastname: Park
authors.forename: Je-Duck
authors.initials: JD
authors.lastname: Suh
authors.forename: Pill-Hoon
authors.initials: PH
authors.lastname: Choung
mesh_terms: D000293:Adolescent; D000328:Adult; D053687:Adult Stem Cells / Q000166:cytology*; D000539:Alveolar Process / Q000166:cytology; D001641:Bicuspid / Q000166:cytology; D001854:Bone Marrow Cells / Q000166:cytology; D002648:Child; D003739:Dental Cementum / Q000473:pathology; D003743:Dental Enamel / Q000473:pathology; D003782:Dental Pulp / Q000473:pathology; D003804:Dentin / Q000473:pathology; D005260:Female; D005455:Fluorescent Antibody Technique; D018398:Homeodomain Proteins / Q000032:analysis*; D006801:Humans; D015151:Immunoblotting; D060850:LIM-Homeodomain Proteins; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D008964:Molar, Third / Q000166:cytology; D009810:Odontoma / Q000473:pathology*; D010513:Periodontal Ligament / Q000166:cytology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014070:Tooth / Q000166:cytology*; D014157:Transcription Factors; D016335:Zinc Fingers
chemical_list: D018398:Homeodomain Proteins; C112960:LIM homeobox protein 8; D060850:LIM-Homeodomain Proteins; D012333:RNA, Messenger; D014157:Transcription Factors