Many recent studies have shown that hepatocyte growth factor (HGF) is pleiotropic. Indeed, HGF has been reported to act as a mitogen and a morphogen as well as a mitogen. To evaluate the biological significance of HGF in many cell types of different origin, we tested 32 cell lines for expression of HGF mRNA. Of 32 cell lines, 6 lines expressed HGF mRNA. Two glioblastoma cell lines, HGL4 and U138, also expressed its specific receptor (c-met oncogene) mRNA. The conditioned media of HGL4 contained 3.7-fold higher HGF activity compared to FaONeO cells as a negative control. Recombinant HGF stimulated DNA synthesis of HGL4 cells in a dose-dependent manner. In addition, anti-HGF antibody inhibited DNA synthesis of these cells. These findings suggest that coexpression of HGF and c-met oncogene stimulates growth of HGL4 glioblastoma cells.