Objective:To explore the effect of BANCR in reversing cisplatin(DDP) resistance of human non-small cell lung cancer(NSCLC)A549/DDP cell line and its related mechanisms. Methods:The real-time fluorescent quantitative PCR(qRT-PCR) was used to detect BANCR expression differences in DDP-resistant A549/DDP cells and its parent cell line A549.Overexpress BANCR in A549/DDP cells and use MTT assay,colony formation assay and flow-cytometric analysis to detect A549/DDP cells to DDP drug sensitivity,cell proliferation ability and apoptosis on treatment with DDP.The protein expression of p53 in A549/DDP cells were detected by western blotting. Results:The BANCR expression level in A549/DDP cell line was significantly lower than that in A549 cell line (P < 0.05). Ectopic BANCR expression in A549/DDP cells could produce the following effects:compared to the control group,the half inhibition concentration (IC50) of DDP in A549/DDP/BANCR cells lower (P < 0.05),proliferation of A549/DDP/BANCR cells diminished(P < 0.05),apoptosis on treatment with DDP increased(P < 0.05). Furthermore,the protein expressions p53 was upregulated in BANCR transfected group than those in empty vector. Conclusion:BANCR reverses the resistance of A549/DDP cells to DDP through induction of apoptosis,diminished cell proliferation,up-regulating the expressions of p53 protein.