(A) Reverse transcription-quantitative polymerase chain reaction was used to determine the miR-429 level in H1229 cells transfected with miR-429 mimic, miR-429 inhibitor or scramble miR mimic as a NC. (B) An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to examine cell proliferation in each group. Non-transfected H1229 cells were used as a control. **P<0.01 vs. control. miR, microRNA; NC, negative control; OD, optical density.