Immunohistochemical expression of 14-3-3 sigma protein in intraductal papillary-mucinous tumor and invasive ductal carcinoma of the pancreas.
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.
Okada
Toshiyuki
T
Departments of General Surgical Science, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Maebashi, Gunma, Japan.
Masuda
Norihiro
N
Fukai
Yasuyuki
Y
Shimura
Tatsuo
T
Nishida
Yasuji
Y
Hosouchi
Yasuo
Y
Kashiwabara
Kenji
K
Nakajima
Takashi
T
Kuwano
Hiroyuki
H
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
D048948:14-3-3 Proteins; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D005092:Exonucleases; D005095:Exoribonucleases; C413442:SFN protein, human