COX-2 is a key factor of MIF promoted proliferation. (A) CCK8 assay showed the proliferation of BPH-1 cells treated with control, rMIF (100 ng/ml), rMIF (100 ng/ml)+celecoxib (5 µM) and celecoxib (5 µM), respectively. Data are presented as mean±s.d., n=3. (B) CCK8 assay showed the proliferation of PWR-1E cells treated with control, rMIF, rMIF+celecoxib and celecoxib, respectively. Data are presented as mean±s.d., n=3. (C) JC-1 assay showed the growth rates of the BPH-1 cells treated by control, rMIF, rMIF+celecoxib and celecoxib, respectively. Data are presented as mean±s.d., n=3. (D) JC-1 assay showed the growth rates of the PWR-1E cells treated by control, rMIF, rMIF+celecoxib and celecoxib, respectively. Data are presented as mean±s.d., n=3. *P<0.05. Statistical analyses were performed using ANOVA followed by Tukey's test for multiple comparison.