Figure 1.

TQ sensitizes colorectal cancer cells to radiation and reduces their cell viability and colony forming ability. (a,b) HCT116 and HT29 cells were either left untreated or were incubated with TQ alone, IR alone (2 Gy) or combinations for 48 or 72 h. At the specific time point, cell viability was determined using trypan blue exclusion assay. (c–f) Clonogenic survival assay was used to determine effect of TQ and IR on the long-term survival of HCT116 (c) and HT29 (d) cells. Cells were treated with TQ, IR, or combinations, after which they were collected and seeded in treatment-free media at low density. After 7–10 days, the resulting colonies were fixed, stained with crystal violet and counted. Representative images of HCT116 (e) and HT29 (f) colonies are shown. Results are expressed as percentage of the studied group as compared to its control. Data represent an average of three in-dependent experiments. The data are reported as mean ± SEM (* p < 0.05; ** p < 0.01; *** p < 0.001).