Fig. 6.
Compound 23 sensitizes CDDP-induced cell death against A549/CDDP cells. (A) Cytotoxicity of CDDP against the A549 and A549/CDDP cells was determined by MTT assay. Cells were treated with various concentrations CDDP for 24 h. (B) Cytotoxicity of 23 against the A549 and A549/CDDP cells were determined by MTT assay. Cells were treated with various concentrations 23 for 24 h. (C) Cells were treated with indicated dose of 23 (1.25 μM) or CDDP (32.5 μM) for 24 h. Cell viability was detected by MTT assay. (D) Effect of combined treatment on the ROS in A549/CDDP cells was detected by flow cytometry. Cells were treated as above and stained with DCFH-DA. (E) Effect of combined treatment on lipid peroxidation was detected by flow cytometry. Cells were treated as above and stained with C11-BODIPY. (F) Effect of combined treatment on the cell apoptosis was detected by flow cytometry. Cells were treated as above and stained with AV and PI. **P < 0.01, *P < 0.05, relative to control group, ##P < 0.01 relative to 23 group, &&P < 0.01 relative to CDDP group. (G) Western blot was performed to examine the effects of combined treatment on the expression of BAX, cleaved caspase-3, cleaved caspase-9 and γ–H2AX. (H) Western blot was performed to examine the overexpression of Prdx I/II in A549 cells. Infected cells were harvested at the indicated times and cell lysates were blotted for proteins as indicated. (I, J) MTT assay was performed to examine the effect of Prdx I/II on cell viability induced by 23 and CDDP. Infected cells were treated with different concentration of 23 or CDDP as indicated for 24 h. (K) Western blot was performed to examine the effect of Prdx I siRNA and Prdx II siRNA on expression of Prdx I/II in A549/CDDP cells. Infected cells were harvested at the indicated times and cell lysates were blotted for proteins as indicated. (L, M) MTT assay was performed to examine the effect of Prdx I/II on cell viability induced by 23 and CDDP. Infected cells were treated with different concentration of 23 or CDDP as indicated for 24 h.