miR-34a mediates oxaliplatin resistance of colorectal cancer cells by inhibiting macroautophagy via transforming growth factor-β/Smad4 pathway

Figure 3 miR-34a directly regulated Smad4 expression and TGF-β inhibition in colorectal cancer cells. A: miRNA target prediction screened one computative miR-34a binding site at Smad4 3’-UTR; B: qRT-PCR analysis of expression of miR-34a treated with miR-34a mimics in HT29 and HT29-OXA cells (^aP < 0.05). U6 was used as a loading control. Error bars represent mean ± SD from three independent experiments; C: 3’-UTR luciferase reporter assay showed a reduction of relative luciferase activity of wild-type Smad4 3’-UTR by pre-miR-34a in HT29 and HT29-OXA cells (^eP < 0.001); D: Western blotting of Smad4 and TGF-β expression in HT29 and HT29-OXA cells treated with miR-34a mimic. β-actin expression level was used as internal loading control.