NSCLC cell lines (A549 and H1299) and human bronchial epithelioid cell line 16HBE were purchased from BNCC (Beijing). A549/DDP and H1299/DDP cells were constructed as described in a previous study.15 Cells were cultivated in RPMI‐1640 (Hyclone) with 10% FBS (Hyclone) and 1% penicillin/streptomycin (Invitrogen).