Fig. 1

miR-200a promoted chemoresistance in breast cancer cell lines. a MDA-MB-231 cells that had been transfected with the miR-200a mimic or the miR-Ctrl were treated with 5 μM cis-platin and stained with TUNEL-TMR red, phalloidin-FITC for actin and DAPI for the cell nucleus. b The confocal TUNEL analysis showed that the miR-200a-transfected MDA-MB-231 cells had lower levels of apoptosis than the miR-Ctrl-transfected MDA-MB-231 cells. c Apoptosis was evaluated in ZR-75-30 cells after treating with cis-platin and staining with Annexin-V at 48 h. The flow cytometry profile depicts Annexin-V-FITC staining on the x-axis and PI staining on the y-axis. The number represents the percentage of early apoptotic cells in each condition, and (d) Mean ± SEM of apoptotic cells from three different experiments. e After cis-platin treatment, the transfected cells were lysed for western blotting. The protein levels of cleaved caspase-3 were normalized to GAPDH