Figure 4

Vosaroxin increases gamma-H2AX retention at 24 hours after irradiation. A high throughput electrochemiluminescent assay to detect gamma-H2AX staining intensity was performed. Cells were plated in 100-mm cell culture dishes, allowed to attach (6 hr) and then incubated in vosaroxin (75 nmol/L) or vehicle containing media (16 hr) prior to irradiation (2 Gy). Cells were harvested at specified time points and stained with sulfo-ester tag conjugated phospho-H2AX detection antibody and luminescence was detected by an electrochemiluminescent imager. Data presented are the mean ± SE from at least three independent experiments. *, p < 0.05 comparing both radiation alone and vosaroxin alone treated cells to the combination treatment.