Long-Term Alteration of Reactive Oxygen Species Led to Multidrug Resistance in MCF-7 Cells

Figure 9

ROS-induced expression of MDR-related factors in MCF-7 cells. (a) Nrf2, (b) NF-κB-p65, and (c) HIF-1α were labeled by double fluorescence staining using DAPI and FITC-labeled antibodies. (A)–(C) MCF-7 cells; (D)–(F) MCF-7/ROS cells (MCF-7 cells treated with 0.1 μM H₂O₂ for 20 weeks). The confocal fluorescence image was captured at magnification of 400x, scale bar = 25 μm. (d) The expression levels of PKCα, c-Myc, and GSTπ were analyzed by western blot. 1, MCF-7/ADM cells; 2, MCF-7 cells (control); 3, MCF-7 cells treated with 0.1 μM ADM; 4, MCF-7 cells treated with 0.1 μM ADM + 2 mM GSH; 5, MCF-7 cells treated with 0.1 μM H₂O₂; 6, MCF-7 cells treated with 0.1 mM GSH; the treatment duration was 20 weeks. Data represents the mean ± SD, , and significant differences relative to control group were indicated as and .

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