Fig. 5

RARα participated in synergistic induction of apoptosis by TPT and ATRA treatment. a After incubation with TPT (40 nM), ATRA (1 μM), or combination for 24 h, the lysates of HL60 cells were prepared for western blot analysis of RARα expression. b. HL60 cells were transfected by negative control (NC) or shRNA of RARα. Western blot analysis showed decreased RARα protein levels in both cell lines. c and d After infection of 72 h, cells were treated with TPT for 24 h. The apoptosis ratio of HL60 cells were detected by flow cytometry. *: Compared to TPT group, p < 0.05. The experiments were performed three times independently, and the error bars represent the SD around the mean. e After transfection of NC or siRNA of RARα, HL60 cells were treated with TPT for indicated minutes. Protein expression of γ-H2AX was analyzed by western blot and densitometry quantification based on α-tublin expression. f After transfection of vector or RARα plasmid, HL60 cells were treated with TPT for indicated minutes and protein expression of γ-H2AX was analyzed by western blot