ABSTRACT
Purpose: IL-1 is a multifunctional proinflammatory cytokine. As the proliferative effects of IL-6 and IL-6 receptor expressions on prostatic cancer cells in response to IL-1 have not been determined, the effects of IL-1 on prostatic cancer cell lines were investigated. Materials and Methods: PC-3 and DU-145 cells were cultured in RPMI-1640 medium containing 10% fetal bovine serum. Cell cultures were supplemented with various concentrations of IL-1 (0, 1, 10, 20 and 40ng/ml), and the MMT growth assay performed. PC-3 and DU-145 cells were treated for 2, 4, 8, 12 and 24 h both with and without IL-1. IL-6 and IL-6 receptor (IL-6R) mRNA expressions were investigated using RT-PCR, and the IL-6 levels in cultured supernatant measured by ELISA. Results: The viability of both PC-3 and DU-145 cells decreased after IL-1 treatment (10, 20 and 40ng/mul). With 40ng/ml the IL-1, IL-6 and IL-6RmRNA expressions were lower in PC-3 cells, but unchanged in DU-145 cells, whereas the IL-6 protein production was higher in both PC-3 and DU-145 cells. Conclusions: IL-1 inhibited the proliferation of both PC-3 and DU145 cells. In the PC-3 cells, IL-1 decreased the expressions of IL-6 and IL-6R mRNA, but paradoxically increased the IL-6 production. In the DU-145 cells, IL-1 treatment did not affect the IL-6 or IL-6R mRNA expressions, but the IL-6 production was increased. This discrepancy between IL-1-induced IL-6 mRNA and protein production may be mediated by modification to the protein synthesis or an increased cellular excretion.