ABSTRACT
Background: For cancer patients' treatment, coronavirus disease 2019 (COVID-19) poses a great challenge. COVID-19 presents as a severe respiratory infection in aging individuals, including patients with lung cancer. COVID-19 may be linked to the progression of aggressive lung cancer. Conversely, chemotherapy's side effects, such as chemotherapy resistance, acceleration of cellular senescence, could worsen COVID-19. Considering the above-mentioned facts, our present work was aimed to investigate the role of paclitaxel (a chemotherapy drug) in cell proliferation, apoptosis, and cellular senescence of gefitinib-resistant NSCLC cells (PC9-MET) and reveal the underlying mechanisms. Methods: PC9-MET cells were treated with paclitaxel for 72 h and then evaluated by cell viability assay, DAPI staining, Giemsa staining, apoptosis assay, ROS assay, SA-ß-Gal staining, TUNEL assay and western blotting. Results: Our results revealed that paclitaxel significantly reduced the viability of PC9-MET cells and induced morphological signs of apoptosis. The apoptotic effects of paclitaxel were observed by increased levels of cleaved caspase-3, cleaved caspase-9 and cleaved PARP. Additionally, paclitaxel increased ROS production, leading to DNA damage. Importantly, paclitaxel eliminated cellular senescence, which was observed by SA-ß-Gal staining. Conclusion: In light of these findings, paclitaxel could be a promising anticancer drug and could offer a new therapeutic strategy for gefitinib-resistant non-small cell lung cancer (NSCLC) during the COVID-19 pandemic.