Androgen and oestrogen responsiveness of stromal cells derived from the human hyperplastic prostate: oestrogen regulation of the androgen receptor

Abstract

Stromal cells derived from collagenase-digested benign hyperplastic adult prostates were isolated and grown in culture. Androgen and oestrogen receptor status were determined and growth in response to mibolerone (a synthetic androgen) and oestradiol-17 beta was measured. In addition, the ability of oestrogens to regulate the androgen receptor in stromal cells was investigated. [3H]Thymidine incorporation into DNA was stimulated by mibolerone in primary and secondary cultures, but sensitivity was lost with subsequent passages. Androgen stimulation of [3H]thymidine incorporation was consistently inhibited by the anti-androgen cyproterone acetate. Oestradiol-17 beta also stimulated [3H]thymidine incorporation into DNA, and this effect was inhibited by the anti-oestrogen tamoxifen. Sensitivity to oestradiol was lost with subsequent passages. A combination of mibolerone and oestradiol was not synergistic in increasing [3H]thymidine incorporation into DNA, but maximal stimulation occurred at 100-fold lower concentrations of mibolerone and oestradiol when the two hormones were applied in combination. Specific high-affinity [3H]mibolerone- and [3H]oestradiol-binding sites were demonstrated by radioligand binding in intact cells. The affinity for oestradiol binding to its receptor exceeded that quantified for mibolerone binding to the androgen receptor, whilst the number of oestradiol-binding sites was approximately tenfold less than that quantified for mibolerone. Treatment with oestradiol down-regulated the number of [3H]mibolerone binding sites 1.7-fold (P < 0.005) as early as day 2 after oestradiol treatment. In conclusion, we successfully cultured stromal cells derived from hyperplastic prostates which retained sensitivity to androgen and oestrogen.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of selective estrogen receptor modulators on cell proliferation and estrogen receptor activities in normal human prostate stromal and epithelial cells

“…Some reported that DHT or estradiol stimulated the growth of stromal cells whereas others published that they did not. 18,[32][33][34][35][36] In our study, the proliferation of prostate epithelial cells was significantly enhanced by adding E2, and that of stromal cells by DHT although the effect was marginal. This may be attributed to the serum and other additives in the culture medium of these slow-growing cells.…”

Monoallelic expression of TMPRSS2/ERG in prostate cancer stem cells

“…This hierarchy of cell types can be segregated into a rare population of SC, responsible for the maintenance of the tissue itself, a rapidly proliferating and expanding transit-amplifying (TA) population and a population committed to differentiation, the committed basal (CB) cell type 11,12 . To study the TMPRSS2/ERG fusion within the basal hierarchy of cell types, we employed a primary culture method 13,14 to generate human prostate basal epithelial cultures, derived from human prostate tissue biopsies isolated directly from patient tumour samples. The presence of the TMPRSS2/ERG fusion at the genomic level in primary cultures and the positive control VCaP cell line (Fig.…”

“…(c) Confirmation of the unique fusion breakpoint by direct sequencing of RT-PCR products from b. (d) FISH detection of TMPRSS2/ERG fusion in total epithelial cell cultures fractionated into SC, TA and CB cell types using the CD133/a2b1 integrin selection process described previously [13][14][15] from patient 60 is shown. (e) Comparable FISH detection of TMPRSS2 and ERG in a sample that does not contain a fusion (f) ERG protein detection (red stain) in selected cell populations from patient sample 60.…”

Androgen receptor signalling in prostate: Effects of stromal factors on normal and cancer stem cells

“…However, one steroid can increase sensitivity for the other (Collins et al, 1994). For example oestrogen can stimulate the proliferation of stromal cells, although the number of binding sites for the synthetic oestrogen oestradiol-17 was found to be much lower than the number of binding sites for androgen (Collins et al, 1994).…”