Nerve growth factor-like substance(s) Â»ereidentified in both condi tioned media of a human prostatic tumor epithelial cell line (TSU-prl) and a human prostatic stromal cell line (UPS) by Western blot analysis and bioassay of neurite out-growth of PC12 cells. Nerve growth factor-/3 (V.I-1 immunofluorescence was also locali/ed to secretory vesicles in the cytoplasm of both the TSl'-prl and UPS cells. Western blot of the TSL'-prl and UPS cell-secreted protein identified an M, 65,000 major protein which immunoreacted with murine NGF antibody. NGK Western blot of UPS cell-secreted protein also identified an M, 42,000 minor band under reduced and nonreduced conditions and an M, 61,000 minor band under reduced conditions. The secreted protein from the TSU-prl cells (SOMg/ml)and UPS (SOMUnil), as well as murine NGF (SOng/ml) or human recombinant NGF (SO ng/ml), stimulated neurite out-growth from PCI2 cells. This neurite out-growth activity was partially inhibited by treatment with NGF antibody. Neither the serum containing growth medium nor bovine serum albumin (SO g/ml) stimulated neurite out growth. The NGF-like secretory protein appeared to play a role in the paracrine regulation of prostatic growth between TSL'-prl cells and 111′S cells. The relative growth of TSU-prl cells, as indicated by |'H|thymidine incorporation, in response to IIPS secretory protein was stimulated 2.8- fold in a dose-dependent manner. In the converse interaction, the relative growth of UPS cells in response to TSU-prl secretory protein was stimulated 1.8-fold in a dose-dependent manner. Immunoneutralization of TSU-prl and UPS secretory protein was performed with antibody against NGF, acidic fibroblast growth factor, and basic fibroblast growth factor. Removal of the NGF-like protein from the maximal stimulatory dose of TSU-prl secretory protein (100 fig/ml) with NGF antibody reduced UPS proliferation to 52% of maximal levels, and immunoneuir; ili/aliini of the NGF-like protein in the maximal stimulatory dose of HPS secretory protein (20 g/ml) also reduced TSU-prl proliferation to 16% of maximal levels. Addition of normal rabbit serum or prior immunoprecipitation of either TSU-prl or HPS secretory protein with antibody against acidic fibroblasl growth factor and basic fibroblast growth factor did not inhibit the proliferation of either cell type. These results suggest that TSU-prl tumor cells and HPS cells secrete NGF-like protein(s) which modulate their paracrine interactive growth in vitro.
|Original language||English (US)|
|Number of pages||7|
|State||Published - Jun 1991|
ASJC Scopus subject areas
- Cancer Research