Mesothelin is overexpressed in pancreaticobiliary adenocarcinomas but not in normal pancreas and chronic pancreatitis.
Mesothelin, a cell surface glycoprotein present on normal mesothelial cells, has been reported to be expressed in pancreatic adenocarcinomas. We conducted this study to fully characterize mesothelin expression in surgically resected, formalin-fixed, paraffin-embedded tissue specimens of 18 pancreatic adenocarcinomas, 9 adenocarcinomas of the ampulla of Vater, 12 adenocarcinomas of the common bile duct, and 17 cases of chronic pancreatitis. Mesothelin immunostaining was performed using the antimesothelin monoclonal antibody 5B2. All 18 cases (100%) of pancreatic adenocarcinomas showed mesothelin expression, as did 8 (89%) of 9 cases of ampullar adenocarcinoma and all 12 cases (100%) of common bile duct adenocarcinoma. In all cases of pancreaticobiliary adenocarcinoma, the adjacent normal pancreas did not stain for mesothelin. Of 17 specimens of chronic pancreatitis, 16 were negative for mesothelin expression, and 1 case showed weak mesothelin staining of fewer than 5% of normal pancreatic ducts. Our results demonstrated mesothelin expression in the majority of pancreaticobiliary adenocarcinomas and no expression in normal pancreatic tissues and in chronic pancreatitis.
Hassan
Raffit
R
Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4264, USA.
Laszik
Zoltan G
ZG
Lerner
Megan
M
Raffeld
Mark
M
Postier
Russell
R
Brackett
Daniel
D
D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis*; D003135:Common Bile Duct / Q000378:metabolism / Q000473:pathology; D058851:GPI-Linked Proteins; D006801:Humans; D007150:Immunohistochemistry; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D000090204:Mesothelin; D010179:Pancreas / Q000378:metabolism; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D050500:Pancreatitis, Chronic / Q000378:metabolism* / Q000473:pathology
D014408:Biomarkers, Tumor; D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; D000090204:Mesothelin