Novel immunohistochemical marker, integrin αvβ3, for BOP-induced early lesions in hamster pancreatic ductal carcinogenesis

Abstract

N-nitrosobis(2-oxopropyl)amine (BOP)-induced pancreatic ductal carcinomas and early ductal lesions in Syrian hamsters have been reported to show histopathological resem- blance to those in humans. Specific protein expression profiles have been found in human carcinomas, but a detailed molecular approach regarding the dissection of BOP-induced pancreatic carcinogenesis has yet to be determined. The present immu- nohistochemical study of early and advanced hamster lesions focused on five proteins reported to be overexpressed in human patients, to clarify interspecies phenotype similarity. Integrin αvβ3 was found to be overexpressed in the epithelial cells of 13 of 14 atypical hyperplasias and 6 of 6 adenocarcinomas. This overexpression was more frequent than in the remaining four proteins. However, immunoreactivity for α-enolase in epithe- lial cells and for kallikrein 7 and galectin-1/3 in both epithelial and stromal cells was also evident at various frequencies. Thus, similarities of tumor-associated protein expression between human and hamster pancreatic ductal lesions were confirmed, and integrin αvβ3 was identified as a potentially useful immuno- histochemical marker for early lesions in hamsters.