Figure 2.

TQ radiosensitization of colorectal cancer cells is associated with DNA repair inhibition. HCT116 and HT29 cells were either left untreated or incubated with TQ for 24 h followed by irradiation at 2 Gy. Cells were then fixed at 0 min, 10 min and 24 h post irradiation, followed by permeabilization and staining for p-ATR, p-ATM (a,b), and Gamma H2AX (γH2AX) (c,d). Quantification and representative images are shown. Quantification of p-ATM and p-ATR intensity was performed using Carl Zeiss Zen 2012 image software. γH2AX foci were counted using the confocal microscope. Data represent an average of three independent experiments and are reported as mean ± SEM (* p < 0.05; ** p < 0.01 significantly different from control for p-ATM and p-ATR, and from IR for γH2AX). Scale bar for immunofluorescent images is 20 µm.