Figure 4

Effects of MAPK signaling inhibitors on cytokine-induced EPCR shedding (A) and activation of ERK 1/2 pathway (B) in DU-145 and PC-3 prostate cancer cell lines. (A) Cells were pre-incubated with 50 μM PD-98059, 10 μM SB-203580, or 20 μM SP-600125 as indicated for 30 min and thereafter exposed to cytokines at a final concentration of 25 ng/ml for additional 5 h. Results are the means ± SDs of analyses in triplicates and are representative of three independent experiments. * p < 0.05 versus control without cytokines; # p < 0.05 versus cells exposed to cytokines alone. (B) DU-145 and PC-3 prostate cancer cells were incubated with cytokines at a final concentration of 25 ng/ml and 50 μM PD-98059 as indicated for 10 min. Signals of total and phosphorylated forms of ERK 1/2 (P-ERK 1/2) were determined using cell-based ELISA kit. OD, optical density. Results are the means ± SDs of analyses in triplicates and are representative of two similar experiments. * p < 0.05 versus control without cytokines and PD-98059; # p < 0.05 versus cells treated with cytokines, but not with PD-98059.