Expression and processing of gastrin in pancreatic adenocarcinoma

Background: Gastrin is a trophic hormone and promotes growth of gastrointes tinal and nongastrointestinal cancers. Studies both in vitro and in vivo ha ve suggested that pancreatic cancer cells not only have the ability to resp ond to circulating forms of gastrin but also to respond to the autocrine pr oduction of gastrin and its precursors. The aim of this study was to identi fy the expression of CCK-B/gastrin receptor, progastrin, glycine-extended g astrin and amidated gastrin in both normal pancreas and pancreatic adenocar cinoma. Methods: Tissue sections from patients with normal pancreas (n = 10) and pa ncreatic cancer (n = 22) were assessed using immunohistochemical methods fo r CCK-B/gastrin receptor, progastrin, glycine-extended gastrin and amidated gastrin expression. Results: Normal pancreas showed no expression of receptor or gastrin isofor ms except for occasional cells in the islets, Definite expression of CCK-B/ gastrin receptor, progastrin, glycine-extended gastrin and amidated gastrin was observed in 95, 91, 55 and 23 per cent of sections from patients with pancreatic cancer respectively. Conclusion: Pancreatic cancer cells express CCK-B/gastrin receptor and gast rin precursor forms in most patients. Expression of the gastrin precursor f orms is probably related to autocrine production. New therapeutic strategie s need to be developed for the management of pancreatic cancer. Targeting g astrin and its receptor may provide a novel treatment option.