Fig. 6

Comparison of the caspase-3, -8, and -9 activities. U87 and HeLa cells were treated with 40 nM CB01. Cell lysates were prepared after 24 h or 48 h, and their total protein concentrations were quantitated using the Bradford Assay. The caspase-3, -8, and -9 activities of each lysate were measured using fluorescent assay kits. The samples were incubated at 37 °C for 2 h, and their absorbance at 405 nm was measured. All the data are expressed as mean  ±  SEM. Statistical significance was evaluated using the paired sample t test; ns  =  p  >  0.05, *p  < 0.05, **p  < 0.01, and ***p  < 0.001