Early apoptosis was not induced by overexpression of miR-206 in A549 or HCC827 cells. A549 and HCC827 cells were transfected with 40 nM negative control or miR-206 mimics for 48 h. Cells were subjected to flow cytometry for cell apoptosis analysis. The results are presented as the mean ± standard deviation (*P<0.05). miR, microRNA; NC, negative control; A, annexin V; FITC, fluorescein isothiocyanate; Q, quadrant; Comp, composition.