title: Tp53/p53 status in keratoacanthomas.
abstract: BACKGROUND
  Keratoacanthoma (KA) is a common keratinocytic skin neoplasm that typically develops rapidly and undergoes complete spontaneous regression. As the pro-apoptotic p53 protein may be involved in the lifecycle of KA, we studied the p53 status throughout the main stages of KA that include proliferation, maturation and regression in a large series of lesions.
  
  
  METHODS
  One-hundred and twenty-four KAs were characterized with respect to age of the lesions both clinically and histopathologically, in addition to phenotypic characteristics such as cellular atypia, infiltration, inflammation and fibrosis. Tp53 mutations were detected by capillary electrophoresis, and p53 protein levels were assessed by immunohistochemistry.
  
  
  RESULTS
  Tp53 mutations were detected in 49 cases (39.5%) and were associated with high p53 protein levels (p = 0.007) and histopathologic age of the lesions (p = 0.044). Significant association was also seen between high p53 protein levels and atypia (p = 0.036), whereas the association with infiltration showed borderline significance (p = 0.057). High p53 protein levels were significantly associated with gene mutations in transplanted, but not in non-transplanted patients.
  
  
  CONCLUSIONS
  We show a high frequency of Tp53 mutations in KAs that is associated with increased p53 levels. The results indicate a role for the p53 protein in KA development.
authors.affiliation: Department of Pathology, Oslo University Hospital, Rikshospitalet, Oslo, Norway.|Institute of clinical medicine, Department of Pathology, Akershus University Hospital, Lørenskog, Norway.
authors.forename: Sarita
authors.initials: S
authors.lastname: Joshi
authors.affiliation: Department of Pathology, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
authors.forename: Aasa R
authors.initials: AR
authors.lastname: Schjølberg
authors.affiliation: Institute for Cancer Research, The Norwegian Radium Hospital, Oslo, Norway.
authors.forename: Per Olaf
authors.initials: PO
authors.lastname: Ekstrøm
authors.affiliation: Department of Pathology, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
authors.forename: Paula M
authors.initials: PM
authors.lastname: De Angelis
authors.affiliation: Department of Biostatistics, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
authors.forename: Manuela
authors.initials: M
authors.lastname: Zucknick
authors.affiliation: Institute of clinical medicine, Department of Pathology, Akershus University Hospital, Lørenskog, Norway.
authors.forename: Solveig Norheim
authors.initials: SN
authors.lastname: Andersen
authors.affiliation: Department of Pathology, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
authors.forename: Ole Petter F
authors.initials: OP
authors.lastname: Clausen
mesh_terms: D000328:Adult; D000368:Aged; D004252:DNA Mutational Analysis; D019075:Electrophoresis, Capillary; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007636:Keratoacanthoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012878:Skin Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics
chemical_list: C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53
keywords: Tp53 mutation; keratoacanthoma; p53