title: Differential expression of transcription factors Snail, Slug, SIP1, and Twist in ameloblastoma.
abstract: BACKGROUND
  Epithelial-to-mesenchymal transition (EMT) via the mechanism of transcription repression is a crucial process for the induction of invasiveness in many human tumors. Ameloblastoma is a benign odontogenic epithelial neoplasm with a locally infiltrative behavior. Twist, an EMT promoter, has been implicated in its invasiveness. The roles of the other transcription factors remain unclarified.
  
  
  METHODS
  Four transcription factors, namely Snail, Slug, SIP1, and Twist, were examined immunohistochemically in 64 ameloblastoma [18 unicystic (UA), 20 solid/multicystic (SA), 4 desmoplastic (DA), and 22 recurrent (RA)].
  
  
  RESULTS
  All four transcription factors were differentially expressed in ameloblastoma [Snail: n = 60/64 (94%); Slug: n = 21/64 (33%); SIP: n = 18/64 (28%); Twist: n = 26/64 (41%)] (P < 0.05). Their distribution patterns were heterogeneous and were not significantly different between the tumor invasive front and central area (P > 0.05). Intracellular protein localization was predominantly nuclear for Snail, cytoplasmic>nuclear for Slug and SIP1, and cytoplasmic/nuclear for Twist. Overexpression of Snail in most subsets (UA = 18/18; SMA = 19/20; DA = 4/4; RA = 19/22) compared with the other transcription factors (P < 0.05) and selective expression for Slug, SIP1, and Twist in squamous/keratinous foci and at sites of epithelial cystic degeneration were among the main observations made. Stromal cells surrounding immunoreactive tumor cells tended to stain positive.
  
  
  CONCLUSIONS
  Present findings suggest that these transcription factors probably play differential roles in mediating local invasiveness in ameloblastoma. Overexpression of Snail in most subsets suggests that this molecule is most likely the prototype transcription factor involved in inducing EMT in the ameloblastoma.
authors.affiliation: Department of Oral Pathology, Oral Medicine and Periodontology, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Chong Huat
authors.initials: CH
authors.lastname: Siar
authors.forename: Kok Han
authors.initials: KH
authors.lastname: Ng
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000564:Ameloblastoma / Q000737:chemistry* / Q000473:pathology; D002467:Cell Nucleus / Q000648:ultrastructure; D002648:Child; D002675:Child, Preschool; D003593:Cytoplasm / Q000648:ultrastructure; D058750:Epithelial-Mesenchymal Transition / Q000502:physiology; D004848:Epithelium / Q000473:pathology; D005260:Female; D006801:Humans; D007573:Jaw Neoplasms / Q000737:chemistry* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009419:Nerve Tissue Proteins / Q000032:analysis; D009687:Nuclear Proteins / Q000032:analysis; D016601:RNA-Binding Proteins / Q000032:analysis; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors / Q000032:analysis*; D051879:Twist-Related Protein 1 / Q000032:analysis; D055815:Young Adult; D016335:Zinc Fingers
chemical_list: C108381:GEMIN2 protein, human; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; C000604407:SNAI1 protein, human; D000071250:Snail Family Transcription Factors; C103173:TWIST1 protein, human; D014157:Transcription Factors; D051879:Twist-Related Protein 1
keywords: SIP1; Slug; Snail; Twist; ameloblastoma; immunohistochemistry