Regulation of proliferation and differentiation of prostatic stromal cells by oestradiol through prostatic epithelial cells in a paracrine manner.
OBJECTIVE
To characterize a paracrine effect of prostatic epithelial cells in the presence or absence of oestradiol on the differentiation and proliferation of prostatic stromal cells.


METHODS
Conditioned media (CM) collected from a prostatic epithelial cell line (BPH-1), which was pre-treated with different concentration of oestradiol, were added to cultures of primary prostatic stromal cells. The proliferation rates of stromal cells were determined using a tetrazolium assay. The mRNA level was analysed by real-time reverse transcription-polymerase chain reaction (RT-PCR), and the protein level of smooth muscle myosin heavy chain (SM-MHC), fibronectin and collagen IV were determined with Western blotting, enzyme- linked immunosorbent assay and radioimmunoassay, respectively. The expression of transforming growth factor beta1 (TGF beta 1) in the BPH-1 cell line was analysed.


RESULTS
The rate of proliferation of stromal cells increased when they were cultured with CM harvested from oestradiol-treated BPH-1 cells, but there was no remarkable change when they were cultured with CM from untreated cells. The level of smoothelin mRNA and SM-MHC protein increased after treatment with CM from BPH-1. The CM from BPH-1 with oestradiol stimulation was more effective in stimulating smoothelin mRNA and SM-MHC protein level. The protein level of collagen type IV, but not fibronectin, was up-regulated in the supernatants and cell extracts of CM-treated stromal cells. Oestradiol enhanced the expression and secretion of TGF beta 1 in BPH-1 cells. TGF beta 1-neutralizing antibody abrogated the effect of BPH-1 CM on the synthesis of collagen IV and SM-MHC in stromal cells.


CONCLUSIONS
These results suggest that oestradiol-stimulated proliferation and differentiation of prostatic stromal cells could be regulated by factors secreted from prostatic epithelial cells.
Wu
Quan
Q
Bioactive Materials Key Laboratory of Ministry of Education, Institute for Molecular Biology, Nankai University, Tianjin, PR China.
Shi
Jiandang
J
Chen
Linfeng
L
Wang
Chun-Yu
CY
Park
Irwin
I
Lee
Chung
C
Zhang
Ju
J
D015153:Blotting, Western; D016022:Case-Control Studies; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology; D004958:Estradiol / Q000494:pharmacology*; D005109:Extracellular Matrix / Q000187:drug effects; D006801:Humans; D008297:Male; D011467:Prostate / Q000473:pathology*; D011468:Prostatectomy; D011470:Prostatic Hyperplasia / Q000473:pathology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017154:Stromal Cells / Q000187:drug effects / Q000473:pathology; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*; D015854:Up-Regulation
D017077:Culture Media, Conditioned; D053773:Transforming Growth Factor beta1; D004958:Estradiol