Figure 5: REM-induced JNK reduces MCF-7/Dox cell viability. (a) Cells were transfected with YB-1 and treated with REM 48 hours. The MTT experiments were performed in triplicate. N.S. indicates no significance in statistics. *, . (b) Cells were pretreated with SP600125 for 30 minutes and then treated with REM alone or REM plus doxorubicin for another 48 hours. The MTT assays were done in triplicate. (c) Cells were transfected with the indicatives for 48 hours and then subjected to the MTT assays. The experiments were performed in triplicate. *, . (d) Schematic illustration. YB-1-dependent MDR1 expression results in multidrug resistance by drug efflux (herein, doxorubicin). REM treatment activates JNK1/2, which blocks YB-1 nuclear translocation and induces c-Jun/c-Fos inhibition of YB-1-dependent MDR1 expression. Thus, REM results in the decrease of multidrug-resistant cancer cell viability with a loss of multidrug-resistant phenotype.