title: Comparison of the value of PCNA and Ki-67 as markers of  cell proliferation in ameloblastic tumors.
abstract: OBJECTIVE
  The aim of this study was to compare among PCNAand Ki-67 as the most reliable immunohistochemical marker for evaluating cell proliferation in ameloblastic tumors.
  
  
  METHODS
  Observational, retrospective, and descriptive study of a large series of ameloblastic tumors, composed of 161 ameloblastomas and four ameloblastic carcinomas, to determine and compare PCNA and Ki-67 expression using immunohistochemistry techniques.
  
  
  RESULTS
  When analyzing Ki-67 positivity, the desmoplastic ameloblastoma demonstrated a significantly lower proliferation rate (1.9%) compared with the solid/multicystic and unicystic ameloblastomas and ameloblastic carcinomas (p<0.05), whereas the ameloblastic carcinomas displayed a significantly higher rate compared with all of the other ameloblastomas (48.7%) (p<0.05). When analyzing cell proliferation with PCNA, we found significant differences only between the ameloblastic carcinomas (93.3%) and the desmoplastic ameloblastomas (p<0.05). When differences between the immunopositivity for PCNA and Ki-67 were compared, the percentages were higher for PCNA in all types of ameloblastomas and ameloblastic carcinomas. In all cases, the percentages were greater than 80%, whereas the immunopositivity for Ki-67 was significantly lower; for example, the ameloblastic carcinoma expressed the highest positivity and only reached 48.7%, compared to 93.3% when we used PCNA.
  
  
  CONCLUSIONS
  In the present study, when we used the proliferation cell marker Ki-67, the percentages of positivity were more specific and varied among the different types of ameloblastomas, suggesting that Ki-67 is a more specific marker for the proliferation of ameloblastic tumor cells.
authors.affiliation: Research Department, School of Dentistry, Universidad Juárez del Estado de Durango, Durango, México. ronellbologna@hotmail.com
authors.forename: Ronell
authors.initials: R
authors.lastname: Bologna-Molina
authors.forename: Adalberto
authors.initials: A
authors.lastname: Mosqueda-Taylor
authors.forename: Nelly
authors.initials: N
authors.lastname: Molina-Frechero
authors.forename: Ana-Dolores
authors.initials: AD
authors.lastname: Mori-Estevez
authors.forename: Guillermo
authors.initials: G
authors.lastname: Sánchez-Acuña
mesh_terms: D000564:Ameloblastoma / Q000737:chemistry* / Q000473:pathology*; D015415:Biomarkers / Q000032:analysis; D049109:Cell Proliferation; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis*; D009062:Mouth Neoplasms / Q000737:chemistry* / Q000473:pathology*; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis*; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers; D019394:Ki-67 Antigen; D018809:Proliferating Cell Nuclear Antigen