RESUMO
BACKGROUND: Epidermal growth factor receptor (EGFR) gene mutations are the most common driver mutations in non-small cell lung cancer (NSCLC). To prolong the survival of the patients, EGFR tyrosine kinase inhibitors (TKIs) resistance in NSCLC is a major challenge that needs to be addressed urgently, and this study focuses on investigating the mechanism of cigarette smoke (CS) induced Gefitinib resistance in NSCLC. METHODS: PC-9 and A549 cells were cultured in vitro and treated with 1 µmol/L Gefitinib for 4 h and 10% cigarette smoke extract (CSE) for 48 h. Western blot was used to detect Sirtuin 3 (Sirt3) and superoxide dismutase 2 (SOD2) protein expressions; DCFH-DA probe was used to detect intracellular reactive oxygen species (ROS); CCK-8 kit was used to detect cell activity, and EdU was used to detect cell proliferation ability. Sirt3 overexpression plasmid (OV-Sirt3) was transfected in PC-9 and A549 cells and treated with 1 µmol/L Gefitinib for 4 h and 10% CSE for 48 h after N-acetylcysteine (NAC) action. The expressions of Sirt3 and SOD2 were detected by Western blot; the ROS level in the cells was detected by DCFH-DA probe, and the cell activity was detected by CCK-8. RESULTS: CSE induced an increase in the 50% inhibitory concentration (IC50) of both PC-9 and A549 cells to Gefitinib (P<0.01) and enhanced the proliferation of PC-9 and A549 cells, suggesting that CS induced Gefitinib resistance in NSCLC. ROS was involved in CSE-induced Gefitinib resistance (P<0.05). CSE induced low expressions of Sirt3 and SOD2 (P<0.01), and Sirt3/SOD2 was associated with poor prognosis in lung cancer patients (P<0.05). OV-Sirt3 in PC-9 and A549 cells reversed CSE-induced Gefitinib resistance (P<0.05) and significantly reduced ROS production. NAC reversed CSE-induced Gefitinib resistance in PC-9 and A549 cells (P<0.05). CONCLUSIONS: The ROS/Sirt3/SOD2 pathway is involved in CS-induced Gefitinib resistance in NSCLC.
Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Fumar Cigarros , Neoplasias Pulmonares , Sirtuína 3 , Humanos , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Sirtuína 3/genética , Sirtuína 3/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/uso terapêutico , Antineoplásicos/uso terapêutico , Sincalida/uso terapêutico , Receptores ErbB/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular TumoralRESUMO
Cigarette smoke (CS)-induced oxidative stress drives the pathogenesis of respiratory diseases, in which the activation and accumulation of reactive oxygen species (ROS) play an important role. Ferroptosis, a regulated cell death induced by Fe2+-dependent, lipid peroxidation, and ROS, is closely related to CS-induced airway injury disease, but its mechanism remains unclear. We found that bronchial epithelial ferroptosis and expression of iNOS in smoking patients were significantly higher than that in non-smokers. The iNOS, induced by CS exposure, was involved in bronchial epithelial cell ferroptosis, whereas genetic depletion or pharmacologic inactivation of iNOS attenuated the CS-induced ferroptosis and mitochondrial dysfunction. Our mechanistic studies found that SIRT3 directly bound to and negatively regulated iNOS to mediate ferroptosis. Moreover, we found that the Nrf-2/SIRT3 signal was deactivated by cigarette smoke extract (CSE)-induced ROS. Collectively, these results linked CS to human bronchial epithelial cell ferroptosis through ROS deactivation of the Nrf-2/SIRT3 signal to promote iNOS expression. Our study provides new insights into the pathogenesis of CS-induced tracheal injury diseases such as chronic bronchitis, emphysema, and chronic obstructive pulmonary disease.
