DEVELOPMENT OF 7 NEW HUMAN PROSTATE TUMOR XENOGRAFT MODELS AND THEIR HISTOPATHOLOGICAL CHARACTERIZATION

Seven human prostate tumor models were established by transplanting tu mor fragments in NMRI athymic nude mice, Once established the tumors w ere serially transplantable in both NMRI and BALB/c nude mice The xeno grafts originated from primary prostatic carcinomas (prostatectomy spe cimens), transurethral resection material, and metastatic lesions (pel t,ic lymph nodes and scrotal skin). Histological examination revealed that, in the course of several mouse passages (8 to 23), tumors retain ed their resemblance to the original patient material, The PC-295, PC- 310, PC-329, and PC-346 tumors are dependent on androgens for their gr owth. The PC-324, PC-339, and PC-374 tumors are androgen independent, although growth of PC-374 tumors still seemed androgen sensitive, All tumors are diploid except for the PC-374, which is tetraploid. The dip loid PC-295 tumor has an additional small population of tetraploid cel ls, All xenografts displayed a heterogeneous expression pattern of the androgen receptor except for the PC-324 and PC-339 ttl,nors ill which the androgen receptor could not be detected. Prostatic acid phosphata se and prostate-specific antigen were retained during serial transplan tation in all tumors but the PC-324 and PC-339, This panel of permanen t human prostate tumor models comprises tumors representing both the a ndrogen-dependent and -independent stages of human prostate cancer wit h various degrees of differentiation and, therefore, is of great value for the study of many aspects of growth and progression of human pros tate cancer.