title: Is podoplanin expression associated with the proliferative activity of ameloblastomas?
abstract: OBJECTIVE
  The aim of this study was to investigate the relationship between podoplanin expression and proliferative activity of ameloblastomas and remnants of the odontogenic epithelium from dental follicles (DF) of unerupted teeth.
  
  
  METHODS
  Thirty-three paraffin-embedded ameloblastomas and thirty-two DF obtained of unerupted teeth were analyzed by immunohistochemistry using anti-human podoplanin and anti-Ki-67 antibodies. Podoplanin expression in odontogenic epithelial cells was evaluated using a scoring method, and the Ki-67 labeling index was determined by the percentage of positive odontogenic cells.
  
  
  RESULTS
  All ameloblastomas displayed podoplanin expression in ameloblast-like cells of the epithelial islands. Membranous expression of podoplanin in ameloblastomas was stronger than in the remnants of odontogenic epithelium (P = 0.001). Statistically significant difference was observed between the cytoplasmic and membranous expression of podoplanin in the remnants of odontogenic epithelium (P = 0.001). The index of epithelial odontogenic proliferative activity, verified by Ki-67 expression, was higher in ameloblastomas vs remnants of odontogenic epithelium (P < 0.001). No statistically significant correlation was identified between podoplanin and the cellular odontogenic proliferative activity in meloblastomas and DF (P > 0.05).
  
  
  CONCLUSIONS
  These results provide evidence that there is no connection between podoplanin immunostaining and odontogenic cellular proliferative activity and suggest a role for membranous podoplanin expression in the local invasion of ameloblastomas.
authors.affiliation: Department of Stomatology, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil. kellentjioe@yahoo.com.br
authors.forename: K C
authors.initials: KC
authors.lastname: Tjioe
authors.forename: D T
authors.initials: DT
authors.lastname: Oliveira
authors.forename: C T
authors.initials: CT
authors.lastname: Soares
authors.forename: J R P
authors.initials: JR
authors.lastname: Lauris
authors.forename: J H
authors.initials: JH
authors.lastname: Damante
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000564:Ameloblastoma / Q000378:metabolism* / Q000473:pathology*; D000565:Ameloblasts / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D049109:Cell Proliferation; D002648:Child; D003593:Cytoplasm / Q000378:metabolism; D003795:Dental Sac / Q000166:cytology / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D006801:Humans; D007573:Jaw Neoplasms / Q000378:metabolism* / Q000473:pathology; D019394:Ki-67 Antigen / Q000096:biosynthesis; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D018709:Statistics, Nonparametric; D014097:Tooth, Unerupted / Q000473:pathology; D055815:Young Adult; D000098853:Podoplanin
chemical_list: D019394:Ki-67 Antigen; D008562:Membrane Glycoproteins; C117468:PDPN protein, human; D000098853:Podoplanin