BAG3 and breast cancer: Among the candidate targets, BAG3, which is closely associated with BC progression, attracted the authors’ attention, and the binding sequence was shown in Fig. 3D. Subsequently, dual luciferase reporter gene assay showed that up-regulating miR-135a-5p remarkably suppressed the luciferase activity of WT-BAG3 reporter and inhibiting miR-135a-5p significantly increased the activity of WT-BAG3 reporter, while that of MUT-BAG3 group was not significantly impacted by miR-135a-5p (Fig. 3E).