Figure 4

Role of JNK in TRAIL plus doxorubicin-induced cell death. (a) HepG2 cells were treated for indicated time with doxorubicin (Dox, 1 μg/ml), TRAIL (10 ng/ml) or the combination of both. Phosphorylated JNK (P-JNK) and total JNK as loading control were detected by western blot. (b) Cells were pretreated for 30 min with increasing concentrations of JNK inhibitor (inhib.) II and then exposed to medium control or 1 μg/ml doxorubicin plus 30 ng/ml TRAIL. (c) Cells were pretreated with 0.03 uM JNK inhibitor V, and then exposed to medium control or doxorubicin plus TRAIL. Cell death was measured by MTT assay, mean values±S.D. of quadruplicates are shown. n=3. ^*P<0.01 (control treated versus JNK inhibitor treated)