Aberrant expression of type I fibroblast growth factor receptor in human pancreatic adenocarcinomas.

Acidic and basic fibroblast growth factors are mitogenic polypeptides that are overexpressed in pancreatic cancer. To determine whether fibroblast growth factors may exert direct effects on pancreatic cancer cells in vivo, we compared the expression of the high-affinity type I fibroblast growth factor receptor (FGFR-1) in human pancreatic tissues. In the normal pancreas, FGFR-1 immunostaining was seen mainly in acinar cells. In pancreatic cancers, FGFR-1 was abundant in ductal-like cancer cells which also exhibited many FGFR-1 mRNA in situ hybridization grains. Analysis by the polymerase chain reaction and RNase protection revealed that the 2-immunoglobulin-like and the 3-immunoglobulin-like forms of FGFR-1 were expressed in all tissue samples, and that the 2-immunoglobulin-like form was overexpressed in the cancer tissues by comparison with the normal tissues. These findings suggest that the 2-immunoglobulin-like form of FGFR-1 may contribute to aberrant autocrine and paracrine pathways in pancreatic cancer.