FIG. 6.

Involvement of ROS in potentiation of JNK/p38 activation in transformed NIH 3T3 cells. (A) Kinetics of ROS production in nonstimulated and CDDP-treated cells. Cells were labeled with the fluorescent dye DCDHF, treated as indicated, and analyzed as described in Material and Methods. Points on the graph are the average values from duplicate samples. Data are from a representative experiment, which was repeated three times with comparable results. (B) DHER14 cells were treated with 5 mM reduced GSH or NAC for 1 h, followed by treatment with 100 μM CDDP. After 16 h lysates were prepared and assayed for JNK or p38 activation by Western blot analysis as done for Fig. 5. (C) NIH 3T3 cells were treated once with H₂O₂ and/or CDDP at the doses indicated. After 16 h cells were lysed, and JNK or p38 activation was determined by immunoblotting.