Figure 3. MiR-20a attenuates TGF-β/Smad signaling.

A. Beas2B and HPL1A cell clones with miR-20a stable expression and their parental and control vector cells were serum starved for 2 h and then treated with 5 ng/ml TGF-β for 1 h. Indicated proteins were analyzed by western blotting. B. Beas2B cells with miR-20a stable expression and control vector cells were transfected with TGF-β responsive luciferase vector (CAGA)₉ MLP-Luc. Transfeted cells were treated with 5 ng/ml TGF-β for 22 h. Luciferase and Δ-galactosidase activities were measured. **P < 0.01, vs. TGF-β treated vector cells (Vec). C. and D. QRT-PCR analysis was performed with total RNA from cells in “Figure 3A” treated with 5 ng/ml TGF-β for 5 h. *P < 0.05, vs. TGF-β untreated cells in each group, #P < 0.05, ##P < 0.01, vs. TGF-β treated cells in parental and vector groups.