Effects of Ad/shBcl-xL on the in vitro sensitivity of LoVo cells to irradiation. A. Clonogenic survival after varying doses of irradiation exposure. The mock, Ad/shcontrol or Ad/shBcl-xL-infected LoVo cells were irradiated followed by a further incubation for 24 h at 37°C before trypsinization and plating for clonogenic survival. After 10-14 days incubation, colonies were stained, and the surviving fraction was determined. The log survival was formed to the number of cells plated, after correcting for plating efficiency. B. Flow cytometry analysis of apoptosis in mock LoVo or LoVo cells infected with Ad/shcontrol or Ad/shBcl-xL. C. Flow cytometry analysis of apoptosis in mock, Ad/shcontrol or Ad/shBcl-xL-infected LoVo combined with irradiation treatment (8.0 Gy). Error bars, the mean ± SD in three experiments (n = 3). *P < 0.05 vs mock.