title: Metallothionein immunoexpression in selected benign epithelial odontogenic tumors.
abstract: BACKGROUND
  Odontogenic tumors exhibited variable biologica behaviors. Metallothionein (MT) is correlated with the cellular homeostasis of essential metals, cellular differentiation, and proliferation. The core goals of this study are (i) to report and to compare MT expression among benign epithelial odontogenic tumors; (ii) to correlate MT with cellular proliferation index; and (iii) to evaluate the influence of the inflammatory infiltrate on MT expression.
  
  
  METHODS
  Ten cases of solid ameloblastomas (SABs), 4 squamous odontogenic tumors (SOTs), 5 adenomatoid odontogenic tumors (AOTs), and 3 calcifying epithelial odontogenic tumors (CEOTs) were subjected to immunohistochemical to anti-MT, anti-Ki-67, and anti-PCNA. Statistical analysis was performed using BioEstat(®) 4.0.
  
  
  RESULTS
  Metallothionein staining was found to be the highest in the SABs (93.1%), followed by SOTs (52.9%), AOTs (38.4%), and CEOTs (0%). MT staining exhibited statistically significant differences between the SABs and the SOTs (P = 0.0047) and the AOTs (P = 0.0022). A weak-to-strong positive correlation between IMT and IK or IP was observed in SABs and SOTs, whereas a strong negative correlation was observed in AOTs. No differences in IMT, IK, and IP were observed between inflammation groups A and B.
  
  
  CONCLUSIONS
  The increased MT expression observed in the SABs might be correlated with clinical behavior (local invasiveness and high rate of recurrence). In the SABs and SOTs, MT plays a role in the stimulation of cellular proliferation. In contrast, MT can inhibit cellular proliferation in the AOT. The IMT, IK, and IP are not affected by inflammation.
authors.affiliation: School of Health and Biosciences, Pontifícia Universidade Católica do Paraná, Curitiba, Brazil.
authors.forename: Aline Cristina Batista Rodrigues
authors.initials: AC
authors.lastname: Johann
authors.forename: Patrícia Carlos
authors.initials: PC
authors.lastname: Caldeira
authors.forename: Giovanna Ribeiro
authors.initials: GR
authors.lastname: Souto
authors.forename: Mauro Henrique Nogueira Guimarães
authors.initials: MH
authors.lastname: de Abreu
authors.forename: Maria Cássia Ferreira
authors.initials: MC
authors.lastname: Aguiar
authors.forename: Ricardo Alves
authors.initials: RA
authors.lastname: Mesquita
mesh_terms: D000564:Ameloblastoma / Q000737:chemistry / Q000473:pathology; D049109:Cell Proliferation; D003238:Connective Tissue / Q000473:pathology; D004847:Epithelial Cells / Q000737:chemistry / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis; D008214:Lymphocytes / Q000473:pathology; D008668:Metallothionein / Q000032:analysis*; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D051527:Odontogenic Tumor, Squamous / Q000737:chemistry / Q000473:pathology; D009808:Odontogenic Tumors / Q000737:chemistry* / Q000473:pathology; D010950:Plasma Cells / Q000473:pathology; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D012878:Skin Neoplasms / Q000737:chemistry / Q000473:pathology
chemical_list: D019394:Ki-67 Antigen; D018809:Proliferating Cell Nuclear Antigen; D008668:Metallothionein
keywords: differentiation; odontogenic tumor