Figure 6.

GAS5 Inhibits ABCB1 Expression by Activating the Wnt/β-Catenin Signaling Pathway through the GAS5/miR-221-3p/DKK2 Axis

(A) Putative miR-221-3p binding sites on GAS5 and DKK2. (B) The dual-luciferase reporter assay was performed by transfecting DKK2-WT vector into MCF-7/ADR cells together with miR-221-3p mimics or miR-221-3p mimics+pcDNA-GAS5. (C) The DKK2, β-catenin, c-Myc, and cyclin D1 mRNA expressions in MCF-7/ADR cells transfected with pcDNA-NC or pcDNA-GAS5 and in MCF-7 cells transfected with si-NC or si-GAS5#1 were detected by quantitative real-time PCR. (D) The DKK2, β-catenin, c-Myc, and cyclin D1 protein expressions in MCF-7/ADR cells transfected with pcDNA-NC or pcDNA-GAS5 and in MCF-7 cells transfected with si-NC or si-GAS5#1 were detected by western blot analysis. (E) MCF-7/ADR cells were transfected with pcDNA-GAS5+miR-NC, pcDNA-GAS5+miR-221-3p mimics, pcDNA-GAS5+siRNA-NC, or pcDNA-GAS5+si-DKK2. The GAS5, miR-221-3p, and DKK2 expressions were examined by quantitative real-time PCR. (F) The DKK2, β-catenin, c-Myc, and cyclin D1 mRNA expressions were examined by quantitative real-time PCR. (G) The DKK2, β-catenin, c-Myc, and cyclin D1 protein expressions were examined by western blot analysis. Data are shown as the mean ± SD (n = 3). *p < 0.05, **p < 0.01 versus respective control.