Human benign prostatic hyperplasia heterotransplants as an experimental model.

Benign prostatic hyperplasia is a nonmalignant adenomatous enlargement of the periurethral prostate gland. It is a common disease in older men. In addition to man, spontaneous benign prostatic hyperplasia occurs in chimpanzee and the dog. Alternatives to these spontaneous models are induced benign prostatic hyperplasia, xenografts and in vitro models. Xenografts may be induced by cells cultured in vitro or by the heterotransplantation of primary surgical specimens into immunosuppressed mice. The purpose of this review is to integrate data from more than 30 years of heterotransplantation research in the study of benign hyperplasia of the prostate. Heterotransplantation has provided data regarding the histopathology, morphology, tissue markers, androgen receptor expression, tissue kinetics, take rate and tissue vasculature for this prostate disease. There are advantages, as well as limitations, that have been identified for human prostate disease heterotransplants versus xenotransplantation of cultured cells. Overall, heterotransplanted tissue is better at retaining tissue morphology, pathology, secretory activity, expression of tissue markers and human vasculature of the patient's original specimen. Furthermore, heterotransplanted tissue preserves the three-dimensional tissular architecture of the prostate to maintain critical stromal-epithelial cell interactions.