FIGURE 9.

TP knockdown induced apoptosis in two cell lines via caspase 3 activation and damaged mitochondrial membrane potential. A, annexin V-FITC/PI staining for apoptosis in two MM cells transfected with TP siRNA for 24 h was assessed by flow cytometry analysis. Columns represent the average proportions of apoptotic cells. *, p < 0.05 versus scramble; n = 3. B and C, the effect of TP knockdown on caspase 3 activity in RPMI-8226 and U-266 cells was detected using a caspase 3 activity assay kit. *, p < 0.05 versus scramble; n = 3. D and E, two MM cells were transfected with caspase 3 siRNA or negative control siRNA and then incubated with TP antagonist SQ29548 (20 μm) or DMSO for 24 h. Caspase 3 protein levels were examined by Western blotting analysis (D). Annexin V-FITC/PI staining for apoptosis in two MM cells was assessed by flow cytometry analysis. Columns represent the average proportions of apoptotic cells (E). *, p < 0.05 versus vehicle; #, p < 0.05 versus scramble; n = 3. F, mitochondrial membrane potential of two MM cells transfected with TP siRNA or negative control siRNA was assessed by flow cytometry analysis after incubation with JC-1 dye. The percentages of depolarized cells are presented in the top right quadrants. Columns represent the average proportions of normal, depolarized, and necrotic cells. *, p < 0.05 versus scramble; n = 3. Error bars, S.E.