Decreased miR-144-3p reduced chemosensitivity to DDP induced by knockdown of XIST. (A) Quantitative reverse transcription polymerase chain reaction (RT-qPCR) was performed to measure the level of miR-144-3p in A549/DDP cells or H460/DDP cells transfected with short-hairpin-negative control (sh-NC), sh-XIST, sh-XIST and NC inhibitor, and miR-144-3p inhibitor and sh-XIST. (B–E) The cell survival rate (B, C) and cell proliferation rate (D, E) were measured by the MTT assay in A549/DDP cells or H460/DDP cells. (F) Cell apoptosis was examined in the H460/DDP and A549/DDP cells using flow cytometry. (G–I) The protein levels of MDR1 and MRP1 in A549/DDP and H460/DDP cells was measured by Western blot. (J, K) Cell migration and invasion abilities were increased as shown by the transwell assay. *p <0.05.