Fig. 4

The combination of DCA and PX-478 leads to increased ROS activity. Figure 3 shows the ROS activity assessed by flow cytometric analysis with H2DCFDA in HeLa, MCF-7 and HT-29 cells. Cells were incubated to a confluence of 50% and were then treated with either DCA, PX-478 or the combination for 48 h. The following concentrations of the compounds were used: HeLa—DCA and PX-478, EC₅₀; MCF-7 and HT-29—DCA, EC₅₀ and PX-478, 0.5 x EC₅₀. Panel a shows representative histograms for the analysis of DCF-FITC in HeLa cells. Panel b shows the results in HeLa, MCF-7 and HT-29 cells as bar graphs. Three independent experiments were performed. Significant results compared to the control are marked with an asterisk (*). The combination of DCA and PX-478 led to the highest ROS activity in all cell lines, which was significantly increased compared to that in the corresponding control, DCA-treated and PX-478-treated cells (marked with two asterisks [**])