Effects of p38 MAPK inhibitor on Wip1-silenced SKOV3 cells. (A) SKOV3 cells were either left untransfected (Control, SKOV3 cells), or were transfected with N-siRNA or Wip1-siRNA. The protein expression of p-p38 MAPK, p38 MAPK, p-ERK, ERK, p-JNK and JNK were analyzed by western blot (n=6). Representative images and quantification are reported here, as relative level to β-actin. (B) Effects of p38 MAPK and p-p38 MAPK were analyzed by western blot, following transfection with Wip1 siRNA and treatment with p38 MAPK inhibitor SB203580 for 48 h (10 µM) (n=6). Representative images and quantification are reported here, as the ratio of p-p38/p38. (C) The proliferation rate of SKOV3 cells was analyzed by MTT assay, following transfection with Wip1 siRNA and treatment with p38 MAPK inhibitor SB203580 for 48 h (10 µM) (n=4). Results are plotted as % ratio relative to control (SKOV3 cells). *P<0.05 and **P<0.01 vs. Control (SKOV3 cells). #P<0.01 and ##P<0.01 vs. Wip1-siRNA. Wip1, wild-type p53-induced phosphatase 1; siRNA, small interfering RNA; N-siRNA, non-targeting siRNA; p-, phosphorylated; p38 MAPK, p38 mitogen-activated protein kinase; ERK, mitogen-activated protein kinase 1; JNK, mitogen-activated protein kinase 8.