Growth factor receptor expression in human gastroenteropancreatic neuroendocrine tumours

Background Human gastroenteropancreatic neuroendocrine rumours are function ally and biologically heterogeneous, but their exact growth factor receptor expression pattern, important for onco- and carcinogenesis, remains unknow n. Methods This study searched for the mRNA expression pattern of six tyrosine - and serine/ threonine kinase receptors [hepatocyte growth factor (HGFR), fibroblast growth factor (FGFR), epidermal growth factor (EGFR), insulin-li ke growth factor (IGF)-1R, transforming growth factor (TGF)-beta R1, TGF-be ta R2] together with the five somatostatin receptors in human gastroenterop ancreatic neuroendocrine rumours (gastrinomas, insulinomas, rumours with ca rcinoid syndrome, functionally inactive neuroendocrine tumours) using rever se transcriptase-polymerase chain reaction (RT-PCR). Results EGF receptor was expressed almost exclusively in gastrinomas. Among the: four tumour subtypes, expression frequencies of the somatostatin rece ptors 1 and 5, HGF-, IGF-1-, TGF-beta R1, TGF-beta R2 and the EGF-receptor varied significantly. Conclusions In spite of the common cellular origin of these rumours, differ ences in growth factor receptor expression suggest the existence of differe nt pathways during tumour subtype development.