EXPRESSION OF C-ERBB-2 IN HUMAN PANCREATIC ADENOCARCINOMAS

The c-erbB-2 (neu) gene encodes a transmembrane phosphoglycoprotein (p(185 erbB-2)) which resembles a growth factor receptor-like molecule closely related to the epidermal growth factor receptor. Overexpression of c-erbB-2 induces cell transformation in vitro. Poorer survival rates and elevated recurrance rates following treatment have been shown in patients whose breast adenocarcinomas demonstrate increased c-erbB-2 expression. Using immunoprecipitation and immunoperoxidase staining, we surveyed human cell lines for p(185 erbB-2). Cell lines from most tumor types (e.g. lymphomas, neuroblastomas, melanomas) demonstrated negligible p(185 erbB-2); however, 3 of 6 pancreatic cell lines overexpressed c-erbB-2. Southern blot analysis revealed that c-erbB-2 was amplified in two of these cell lines and was both rearranged and amplified in one of them. Based on these findings, we examined tissue sections from archival specimens of primary human pancreatic adenocarcinomas. A substantial proportion of specimens had increased p(185 erbB-2), as judged by increased immunostaining of the tumor cells. In such pancreatic tumors p(185 erbB-2) may contribute to the malignant phenotype and could provide a target for immunodiagnostic or immunotherapeutic strategies.