MAPK1 and infection: To determine whether the J96 invasion induced IL-8 expression is mediated through the MAPK-dependent pathway, both types of uroepithelial cells were incubated with the specific inhibitor for ERK (PD98059; 30 and 90 μM), JNK (SP600125; 20 and 60 μM), or p38 (SB203580; 10 and 30 μM) for 1 hour before and during infection with J96.