Measurement of androgen sensitivity in the human prostate in in vitro three‐dimensional histoculture

Abstract

We have adopted an in vitro three-dimensional histoculture technique for assay of androgen sensitivity in explants of human benign prostatic tissue. The assay is based on the uptake of 3H-thymidine/micrograms protein in explants of prostate incubated in parallel with dihydrotestosterone (DHT) and hydroxyflutamide (HF) controls. The ratio of 3H-thymidine/micrograms protein in DHT treated samples per 3H-thymidine/micrograms protein in HF treated samples provides an index of androgen sensitivity. The DHT/HF index measured in 24 BPH specimens averaged 3.6. To determine the specificity of the HF effect, we measured the DHT/HF index in a single prostate at different concentrations of HF in the presence of fixed concentrations of DHT (2 x 10(-8) M) and noted a dose-response relationship. In addition we noted no effects of HF on 3H-thymidine incorporation over a range of 2 x 10(-4)M compared to 2 x 10(-7)M, except at the highest concentration. Of surprise was the finding of an average DHT/HF index in 5 different nonprostate tissues, including breast, uterus, colon, kidney, and thyroid, that was similar to the index found in prostates. We plan to adapt this androgen sensitivity assay to measure the DHT/HF index in biopsy-size samples of prostate, since such an assay could then be utilized to determine androgen sensitivity in individual patients with prostate cancer.

Matrix metalloproteinases (MMPs) in fresh human prostate tumour tissue and organ-cultured prostate tissue: Levels of collagenolytic and gelatinolytic MMPs are low, variable and different in fresh tissue versus organ-cultured tissue

“…The low level of enzyme activity in organ culture may be of interest in light of the changes that occurred in prostate tissue over time in culture. These included a proliferative response in the basal epithelial cell population and a concomitant loss of the malignant component (Schrodt and Foreman, 1971;Geller et al, 1992;Nevalainen et al, 1993;Pretlow et al, 1995;Varani et al, 1999; as well as the present report). The present study also demonstrated migration of the proliferating epithelial cells out from the gland across the surface of the tissue.…”

Comparison of androgen-independent growth and androgen-dependent growth in BPH and cancer tissue from the same radical prostatectomies in sponge-gel matrix histoculture

“…The pellet obtained was digested with benzomethonium hydroxide for 3 Hthymidine counts per minute, and the supernate was analyzed for protein concentration. Results were expressed as 3 H-thymidine incorporation per mcg protein for both BPH and cancer tissues histocultured with both HF1 and DHT.…”

“…A total of 23 patient specimens meeting these criteria was available for analysis. Histoculture, as previously described [3] was performed for 5 days. DHT (2 × 10 −8 M) was added daily on days 2-5 of histoculture to one plate of both BPH and cancer; HF1 (2 × 10 −5 M) was added to a parallel plate of BPH and cancer tissue on a similar schedule.…”

“…These studies were done using Trowell medium and tissue suspended on agar rafts supported on a Tantalum mesh. Although Lasnitzki [2] was able to show significant increases in 3 H-uridine incorporation into RNA during incubation of prostatic organ cultures with dihydrotestosterone (DHT) compared to controls, no attempts at quantitation of biological growth parameters by using inhibitors of androgenstimulated growth have been done until the present. In addition, significant advances in tissue-supporting sponge-gel-matrix and the use of defined media, as used in our studies, have been made since that time [3].…”

“…Our histoculture androgen sensitivity technique (HASA), as previously reported [3], provides a realistic reflection of in vivo growth, since stroma and epithelium are maintained in anatomical juxtaposition and the medium is carefully defined.…”