Fig. 2

Curcumin promoted cell cycle arrest and induced cell apoptosis in ESCC cells. a and b EC9706 cells (a) and TE13 cells (b) were treated with 0, 4, 8, 12 or 16 μM curcumin for 24 h and stained with DAPI. Cell cycle analysis were examined by In CELL Analyzer 2000. Data were shown as means±SD. c EC9706 and TE13 cells were treated with indicated concentrations of curcumin for 24 h and then stained with Annexin V-FITC and PI. The percentages of annexin V+ were indicated as means±SD. d EC9706 and TE13 cells were treated with 0, 4, 8 or 16 μM curcumin for 24 h and then analyzed by immunoblotting against PARP and anti-apoptotic proteins (MCL1 and XIAP). GAPDH was used as a loading control. e EC9706 cells were treated with 0, 4 and 8 μM curcumin or 20 μM Z-VAD-FMK for 24 h and then analyzed by immunoblotting against PARP. GAPDH was used as a loading control. f Empty vector (EV) or STAT3 plasmids were transfected into EC9706 cells. Then, the cells were treated with indicated concentrations of curcumin for 24 h, followed by CCK-8 assay. g EC9706 cells were treated with 0, 4 and 8 μM curcumin or 50 ng/ml IL-6 for 24 h, and then cells were prepared for CCK-8 assay. h EC9706 cells were treated with 0, 4 and 8 μM curcumin or 20 μM AG490 for 24 h, and then cells were prepared for CCK-8 assay. ^*p < 0.05, ^**p < 0.01