PTEN and breast cancer: To assess whether miR-130b can directly alter the expression of PTEN in BC cells, wild-type and mutant 3′-UTR PTEN target sequences were cloned into the pGL3 luciferase reporter vector (Fig. 2F), a dual-luciferase reporter assay indicated that the co-transfection of miR-130b mimics and the PTEN-3′-UTR-wild vector into 293 T cells conspicuously repressed the luciferase activity compared to the co-transfection of control vectors and miR-130b mimics.