title: Immunohistochemical expression of 14-3-3 sigma protein in intraductal papillary-mucinous tumor and invasive ductal carcinoma of the pancreas.
abstract: BACKGROUND
  14-3-3 sigma (sigma) has been shown to be overexpressed in pancreatic cancers by a c-DNA microarray technique. However, the expression of 14-3-3 sigma in intraductal papillary-mucinous tumor (IPMT) of the pancreas remains unclear.
  
  
  METHODS
  To evaluate the biological importance of 14-3-3 sigma expression in pancreatic carcinogenesis, immunohistochemistry for 14-3-3 sigma, CDX2, MUC1, MUC2, p53, p16 and Ki-67 was carried out on 33 IPMTs and the results were compared with those for 14 invasive ductal carcinomas (IDCs).
  
  
  RESULTS
  The frequency of 14-3-3 sigma immunoreactivity was 70% and 100% in IPMT and IDC, respectively. The frequency of MUCI and Ki-67 immunoreactivity was significantly higher in IDC than IPMT. In IPMT, dark columnar cell types prevailed over clear columnar cell types in terms of the frequency of the Ki-67 labeling index.
  
  
  CONCLUSIONS
  The overexpression of 14-3-3 sigma was confirmed in both IDC and IPMT. Therefore, this overexpression might occur in the early stages of pancreatic carcinogenesis. Moreover, IPMT composed of dark columnar cells might be a potentially more advanced form than that made up of clear columnar cells.
authors.affiliation: Departments of General Surgical Science, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Maebashi, Gunma, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Okada
authors.forename: Norihiro
authors.initials: N
authors.lastname: Masuda
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Fukai
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Shimura
authors.forename: Yasuji
authors.initials: Y
authors.lastname: Nishida
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hosouchi
authors.forename: Kenji
authors.initials: K
authors.lastname: Kashiwabara
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakajima
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kuwano
mesh_terms: D048948:14-3-3 Proteins; D002288:Adenocarcinoma, Mucinous / Q000378:metabolism* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D021441:Carcinoma, Pancreatic Ductal / Q000378:metabolism* / Q000473:pathology; D002291:Carcinoma, Papillary / Q000378:metabolism* / Q000473:pathology; D005092:Exonucleases / Q000096:biosynthesis*; D005095:Exoribonucleases; D006801:Humans; D007150:Immunohistochemistry; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D048948:14-3-3 Proteins; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D005092:Exonucleases; D005095:Exoribonucleases; C413442:SFN protein, human