Hepatocyte growth factor and c-Met (HGF/c-Met) in adenoid cystic carcinoma of the human salivary gland

Background: Hepatocyte growth factor (HGF) enhances cell growth, morphogenesis, and scattering of various epithelial cells. The aim of this study was to evaluate the hypothesis that HGF/c-Met plays a biological role in the invasive growth of adenoid cystic carcinoma (ACC). Methods: Immunohistochemically, expression of HGF and its receptor c-Met was examined in 15 cases of ACC. To examine the direct effects of HGF on ACC, cell line derived from of ACC (ACC3) was used. The expression of HGF and c-met in ACC3 was investigated by RT-PCR. Analysis of mechanisms of invasion was done by performing scattering assay and matrigel invasion chamber assay. Results: Positive staining of HGF was found in all cases, and that of c-Met was 67%. In ACC3, c-met was expressed, but not HGF. Stimulation of ACC3 by rhHGF induced scattering and promoted invasion. Conclusion: The present results suggest that HGF/c-Met increases tumor cell scattering and may play a part in invasiveness of ACC.