Regulation of prostatic stromal cell growth and function by transforming growth factor beta (TGF beta)

BACKGROUND. The majority of the overgrowth in benign prostatic hyperplasia (BPH) specimens is comprised of connective tissue. Factors that control str omal growth in the prostate are poorly understood; however, members of the transforming growth factor beta (TGF beta) family may be of particular impo rtance in the etiology of BPH. METHODS. Thirty-two low-passage stromal cultures were generated from human prostatectomy specimens. Their stromal origin was confirmed and expression of TGF beta s analyzed by duplex reverse transcription-polymerase chain rea ction (RT-PCR). Challenge experiments were designed to study the effects of exogenous TGF beta 1 on stromal cell growth and synthesis of extracellular matrix components. RESULTS. The expression of TGF beta s 1, 2, and 3 was demonstrated in all 3 2 cell strains. The stromal origin of the cell lines was confirmed. Exogeno us TGF beta 1 added to stromal cultures resulted in inhibition of cell grow th and increased production of type I collagen. CONCLUSIONS. The prostatic stromal cell strains we have developed are a rel iable model for investigating prostatic connective tissue biology. The chal lenge experiments with TGF beta 1 provide further evidence for the involvem ent of TGF beta s in prostatic enlargement, as modulators of the extracellu lar matrix in the absence of growth stimulation. (C) 1999 Wiley-Liss, Inc.