Relative cell viability assays, half-maximal inhibitory concentrations (ICs₅₀) after treatment with an HSP70 inhibitor (VER155008) or a combination of STA-1474 and VER155008.

<p>(A) Cells were treated with HSP70 inhibitor, (VER155008) for 72 h. The relative viability and ICs₅₀ were determined for both cell lines after treatment. (B) BACA or CLAC cells were plated in DMEM media for 24 h and then treated for 72 h with VER155008 only (gray squares), STA-1474 only (black circles) or a combination of VER155008 and STA-1474 concentrations (red triangles) ranging from 0.0625X to 16X their IC₅₀ concentrations. Each graph shows mean ± SEM. Each group was compared to the DMSO control. The dotted line in the y-axis represents the 50% relative viability. *, <i>p</i><0.05; **, <i>p</i><0.01; ***, <i>p</i><0.001. (C) Multi-drug combination dose-effect analysis for the doublet combination of VER155008 and STA-1474 on BACA and CLAC cell lines as measured by the combination index (CI). The CI value definitions are represented in the description column.