Figure 4.

MiR-23a contributes to gefitinib drug resistance. (A) Gefitinib treatment with 5 ng TGF-β1 or Pre-miR-23a or Pre-miR-ctl for 24 h was examined in A549 cells. Then, the cells were incubated in the various concentrations of gefitinib for 72 h. (B) The IC₅₀ values of gefitinib with TGF-β1 and gefitinib after treatment with Pre-miR-ctl or Pre-miR-23a. Each result is expressed as cell viability in the treated samples compared with the untreated sample (100%) for gefitinib therapy. Data are mean ± SD from 3 independent experiments.