ABSTRACT
PURPOSE: In order to characterize the effects of growth factors (EGF, bFGF, KGF) on the regulation of the PSA secretion and the PSA mRNA expression of androgen- dependent LNCaP prostate cancer cell line in serum-free conditions. MATERIALS AND METHODS: LNCaP cells at a concentration of 1x104cells/well, suspended in T-medium containing 2% TCM, were seeded in 24 well plates and were exposed to four different concentrations of these growth factors to evaluate the molecular basis of PSA secretion. Cell numbers were evaluated by crystal violet assay on day 5. PSA concentrations in conditioned medium were determined on day 5, and PSA/cell number was also calculated to measure net PSA secretion per cell. PSA mRNA expression of LNCaP was assessed by RT-PCR and Northern blot analysis on day 5. RESULTS: bFGF and KGF had significant stimulatory effects (p<0.05) on the proliferation of LNCaP. However, EGF had minimal, not significant, growth stimulatory effects. EGF, bFGF and KGF did not increase the PSA secretion of LNCaP and no apparent increase or decrease in the steady-state levels of the PSA mRNA expression of LNCaP could not be detected in spite of addition of EGF, bFGF and KGF. CONCLUSIONS: bFGF and KGF, not EGF, directly stimulate the proliferation of LNCaP cells. However, bFGF and KGF as well as EGF do not affect the PSA secretion and the PSA mRNA expression of androgen-dependent LNCaP in the absence of androgenic milieu. The regulation of the PSA secretion and the PSA mRNA expression of LNCaP is not directly associated with EGF, bFGF and KGF.