Magnolol Induces Apoptosis Through Extrinsic/intrinsic Pathways and Attenuates NF-κB/STAT3 Signaling in Non-small-cell Lung Cancer Cells

Non-small-cell lung cancer (NSCLC) is the most common type of lung cancer worldwide, and treatment outcomes are still poor. Magnolol, a hydroxylated biphenyl isolated from Magnolia officinalis, was found to be effective against hepatocellular carcinoma via inactivating nuclear-factor-kappa B (NF-B) signaling. However, whether magnolol targets not only NF-B but also other factors in NSCLC and may contribute to the suppression of tumor progression is unclear.Cell viability, flow cytometry, and western blotting assays were used to identify the mechanism of magnolol action in human lung adenocarcinoma cell lines A549 and CL1-5-F4.Our results indicated that magnolol induced cytotoxicity through extrinsic/intrinsic apoptosis signaling and suppressed phosphorylation of signal transducer and activator of transcription 3 (STAT3)/NF-B and expression of their downstream proteins.Magnolol not only induced extrinsic and intrinsic apoptosis signaling but also inactivated STAT3/NF-B and attenuated their signaling of epithelial-mesenchymal transition and metastasis-related protein expression in NSCLC.