Antisense oligodeoxynucteotide against HST-1/FGF-4 suppresses tumorigenicity of an orthotopic model for human germ celt tumor in nude mice

Background Overexpression of the fibroblast growth factor HST-1/FGF-4 gene is thought to mediate growth properties and malignancy in human testicular germ cell tumors. We have studied the effect that an antisense oligodeoxynucleotide against HST-1/FGF-4 suppresses tumorigenicity of a human germ cell tumor. Methods and results To test whether HST-1/FGF-4 could be the target of gene therapy for testicular carcinoma, 20-mer phosphorothioate oligodeoxynucleotides (ODNs) directed against human HST-1/FGF-4 were analyzed for their antitumor activity. The antisense HST-1/FGF-4 ODNs suppressed HST-1/FGF-4 production by NEC8 human nonseminomatous germ cells and inhibited their cell growth in vitro. Furthermore, after orthotopic implantation of NEC8 cells, combined treatment with antisense HST-1/FGF-4 ODNs and Atelocollagen significantly inhibited the growth of testicular tumors as well as the incidence of lymph node metastasis. In contrast, administration of antisense ODNs alone was less effective. Conclusions Collectively, these results indicate that the antisense method against HST-1/FGF-4 gene expression will be a novel therapeutic approach for male germ cell tumors. The use of Atelocollagen-mediated administration of the antisense HST-1/FGF-4 ODNs may be useful in enhancing the effects of antisense therapy. Copyright (C) 2003 John Wiley Sons, Ltd.