MicroRNA-223 Promotes Tumor Progression in Lung Cancer A549 Cells via Activation of the NF-κB Signaling Pathway

Our study aimed to investigate the role of microRNA-223 (miR-223) in lung cancer A549 cells and to further elucidate its possible regulatory mechanism. The expression levels of normal human lung epithelial cell line BEAS-2B and human lung cancer cell line A549 were investigated by quantitative real-time PCR. The A549 cells were transfected with miR-223 inhibitor and miR-223 scramble. Afterward, the effects of miR-223 inhibition on cell viability, invasion, and apoptosis, as well as the expression levels of nuclear factor-κB (NF-κB) and its downstream proteins, were detected. In addition, the NF-κB inhibitor JSH-23 was used to detect the relationship between NF-κB and miR-223. miR-223 was upregulated in human lung cancer A549 cells when compared with BEAS-2B cells. In addition, miR-223 expression was successfully inhibited by the miR-223 inhibitor. Suppression of miR-223 significantly decreased cell viability, inhibited invasion, and induced apoptosis of lung cancer A549 cells. Suppression of miR-223 resulted in a significant decrease in the expression levels of NF-κB and its downstream proteins P-IKBα and P-IKKα/β. After treatment with the NF-κB inhibitor, the inhibitory effects of miR-233 inhibitor on cell invasion, as well as the expression levels of NF-κB and p-p65, were enhanced. Our findings indicate that miR-223 may increase proliferation, promote invasion, and inhibit apoptosis of lung cancer A549 cells via activation of the NF-κB signaling pathway. miR-223 may serve as a potential therapeutic target in lung cancer.