Figure 4. Transfection of microRNA-34 b/c did not induce cell apoptosis but did enhance cell sensitivity to DOX. Caspase 3/7 activity assay was performed on SP6.5 cells transfected with either miR-34b/c or a negative control (NC). Relative caspase 3/7 activity is indicated in comparison to the negative control. Cells were treated without (A) or with DOX (B). Results represent those obtained in three experiments.