Synergistic inhibitory effect of atmospheric pressure plasma and berberine on non‑small cell lung cancer cells via inducing apoptosis.

Background: Non-small cell lung cancer (NSCLC) is a type of lung cancer, the incidence and mortality rate have been high, and the use of monotherapy is easy to make patients develop tolerance. Atmospheric pressure plasma (APP) is an emerging technology for killing cancer cells in recent years, and combination of berberine (BBR) mechanism has not been fully elucidated for NSCLC. The article's primary goal is to investigate the effect of combination on NSCLC and its associated characterization.

Methods and results: Antiproliferative effects were detected by cell viability assay and colony formation, and flow cytometry analysis of apoptosis and cycling showed that the combination synergistically induced apoptosis. Then, extracellular reactive oxygen species (ROS)levels and DCFH-DA-based kits examined intracellular ROS levels, and their effects on mitochondrial membrane potential were measured. Study reveals that co-induced apoptosis is associated with ROS accumulation. Subsequently, Western blotting (WB) detected the expression of epidermal growth factor receptor (EGFR), and the important signaling pathway proteins Ras/ERK and AKT/mTOR. Results showed that it could downregulation of EGFR protein expression and inhibit of activation of ERK/AKT signaling pathways. Simultaneous wound healing assay and epithelial-to-mesenchymal transition (EMT) marker detection were performed for the assessment of migration and EMT ability of NSCLC cells. Combination therapy inhibited migration and EMT of NSCLC cells.

Conclusion: The results of this study show that the combination can synergistically induce apoptosis of NSCLC by regulating ROS production. EGFR downregulation and AKT/ERK signaling pathway inhibition are linked to the synergistic effect.