Testosterone- and phorbol ester-stimulated proliferation in human cultured prostatic stromal cells

Prostatic stromal proliferation may be commonly associated with the development of benign prostatic hyperplasia. In this study, we investigate the role of testosterone and protein kinase C in stimulating cultured stromal cell proliferation. Testosterone increased the uptake of [³H]-thymidine into the human cultured prostatic stromal cells, this was reduced by the protein kinase C inhibitors, bisindolylymaleimide (10 nM) and myristoylated protein kinase C inhibitor (mPKCi, 20 μM), but not by Gö 6983 (1 μM) or Gö 6976 (1 μM). Cells responded to the addition of the PKC activators phorbol 12,13 dibutyrate (PDB), phorbol 12,13 diacetate (PDA), 12-deoxyphorbol 13-acetate (DPA) and 12-deoxyphorbol 13-tetradecanoate (DPT) with proliferation (order of potency DPT≥PDB≫PDA=DPA). The DPT-stimulated proliferative response was inhibited after cells were electroporated with PKCα antisense, but not mismatch oligonucleotides (8 μM). These results indicate that PKCα is involved in the proliferative response of human cultured prostatic stromal cells.