Abstract: Objective Supplying ideal animal model for investigating the mechanism of tumor progress and hormone resistant in prostate cancer. Methods Prostate cancer tissue was obtain via prostatectomy and cut into specimens which orthotopic transplanted into castrate group and sham-castration group nude mice .T hen tumor was harvest and transplant to next generation. until emergence of lymph node metastasis in two groups.. The cell growth curve of cell lines is used to evaluate their growth condition. Boyden chamber is used to evaluate metastasis ability of cell lines. The rate of tumor formation, weight of tumor and range of tumor infiltration of three cell lines was confirmed by subcutaneous transplant. Result The tumorgenic in sham-castration group is 30% without lymph node metastasis in first generation, after three passages is 50%, lymph node metastasis in pelvic is 40%. In castrate group, no tumor formation and lymph node metastasis in first generation. One pelvic lymph node metastasis is find after the forth passages which tumor origin from the lymph node metastasis of sham-castration group.. There are significant differences of cell proliferation transfer ability and tumor rate in vitro and vivo between three cell lines. (p<0.05). Conclusion It's feasible that applying surgical specimens of prostate cancer to establishment .nude mice orthotopic graft model. It is possible to screen heterotransplant tumors and metastasis tumors without hormone dependency by graft rat's lymph node metastasis tumor into castrate nude mice.

Key words: Prostate cancer, Orthotopic xenotransplantation, Tumor model, Androgen resistance