Fig. 2

CPP and TRAIL induces apoptosis in ESCC cells. a. Flow cytometry analysis of YES-2, KYSE-150 and KYSE-510 cells treated with various concentrations of CPP alone or in combination with TRAIL for 24 h. The cells were examined by Annexin V-PE/7-AAD double staining. The lower right and the upper right quadrants indicate the percentage of apoptotic cells. Data are shown as the mean ± SEM. *P < 0.05. b. TUNEL staining of YES-2, KYSE-150 and KYSE-510 cells treated with CPP (100 ng/ml), TRAIL (1 μg/ml) and CPP combination with TRAIL for 24 h. The 2% DMSO treatment group served as a positive control. TUNEL-positive cells that show green fluorescence represent apoptotic cells. Scale bar, 25 μm. Data are shown as the mean ± SEM. **P < 0.01, ***P < 0.001. c. Western blot analysis of changes in the expression of apoptosis-related proteins in cells treated with CPP and TRAIL. YES-2 and KYSE-150 cells were treated with various concentrations of CPP alone or in combination with TRAIL for 24 h