Figure 6

Mechanisms of apoptosis induction by sorafenib and everolimus combination. (A) Bar graph of cell cycle distribution in MES-MM98 cells after 48 h treatment with sorafenib (2.5 μM), everolimus (10 nM) and their combination, compared to untreated control. (B) Induction of apoptosis in MES-MM98 cells, in the absence (blue bars) or in the presence (red bars) of the ROS scavenger BHA. (C) Activation of AMPK by sorafenib treatment. Everolimus potentiated the effect of sorafenib on AMPK activation, reflecting the enhancement of mTOR inhibition and the pro-apoptotic effect of sorafenib and everolimus mediated by c-Jun and p38 activation, triggered by ROS production. PARP cleavage confirmed the apoptotic status. (D) Propidium iodide and Annexin V staining of MES-MM98 cells treated with sorafenib (2.5 μM), everolimus 10 nM, and the p38 inhibitor SB202190. These experiments are representative of 4 different tested cell lines