Localisation of expression of fibroblast growth factors and their receptors in pancreatic adenocarcinoma by in situ hybridisation

Growth factors may play a role in autocrine or paracrine growth control of tumour cells. We have now examined the expression pattern in vivo by in situ hybridization (ISH) on a series of 13 ductal adenocarcinomas of the pancreas using the non-radioactive digoxigenin system to generate specific antisense orientated riboprobes for FGF-1 and FGF-2, and the four FGFRs (FGFR-1, -2, - 3 and -4). We confirmed the expression of both FGF/FGFR by tumour cells, with the presence of a potential autocrine loops in 46% of the cases studied. FGF- 2 and FGFR-3 were the most commonly expressed ligand and receptor (46% and 76% respectively). Endothelial cells lining vessels within and around invasive tumours were frequently positive for expression of FGFR-1 and/or FGFR-3. In the normal pancreas remote from the tumour, the acinar cells were found to have a heterogeneous expression pattern for FGFRs while duct cells, islet cells and stromal components including nerves and vascular endothelium were negative. The data suggest a role for FGFs and their high affinity receptors in the control of growth of human pancreatic adenocarcinoma and its supporting stroma.