Fig. 6.

Effect of STAT3 specific siRNA on H₂O₂-induced cell death. RPTC were transfected with scrambled siRNA or siRNA specific for STAT3, starved for 24 h, and then treated with 1 mM H₂O₂ for 4 h (A and B) or for 30 min (C). Cell viability and apoptosis were assessed by MTT assay (A) and DAPI staining (B), respectively. Cell lysates were prepared for immunoblot analysis using antibodies against p-Ser473-AKT, AKT, p-Tyr705-STAT3, STAT3, or actin (C). Values are means ± SD of 3 independent experiments conducted in triplicates and expressed aspercentage of cells treated with scramble siRNA or total number. Bars with different letters are significantly different from one another (P < 0.05). Representative immunoblots from 3 experiments are shown.