CHARACTERIZATION OF A NOVEL ANDROGEN-SENSITIVE PROSTATE-SPECIFIC ANTIGEN-PRODUCING PROSTATIC-CARCINOMA XENOGRAFT - LUCAP-23

Prostatic carcinoma has proven extremely difficult to establish as cel l lines or xenografts, In this article, we describe a new series of pr ostate cancer xenografts propagated in athymic mice, designated LuCaP 23, developed from prostate metastases harvested at autopsy shortly af ter death, Tumor from three separate metastatic deposits was developed into three xenograft sublines: two from lymph node metastases (LuCaP 23.1 and 23.8) and one from a liver metastasis (LuCaP 23.12), Fluoresc ence in situ hybridization analysis confirms the xenografts are human, Histologically, the xenografts are comprised of columnar epithelial c ells arranged in a glandular pattern, Tumor doubling times range from 11 to 21 days for the three sublines, The cells secrete large amounts of prostate-specific antigen (PSA) with PSA indices of 1.27, 1.63, and 5.21 ng/ml/mm(3) for the mice bearing the LuCaP 23.1, 23.8, and 23.12 sublines, respectively, Following androgen deprivation a temporary de crease in PSA secretion and a decrease in tumor size are noted in most tumors, Eventually, the tumors become androgen independent and resume growth in castrate hosts, The degree of PSA response to castration an d time to PSA nadir correlate with time to progression, Thus, unlike m ost existing models of prostatic carcinoma, this novel xenograft exhib its many phenotypic characteristics of clinical prostatic carcinoma, i ncluding androgen sensitivity, These properties make this xenograft an excellent model for future study.