Abstract 3006: Hyperoxia may be a treatment option for NSCLC

Abstract Introduction: Many anti-tumor drugs have been developed, however, prognosis of NSCLC remains poor and new approaches for NSCLC treatment are expected. Lung is a unique organ whose epithelial cells are directly exposed to oxygen. Hyperoxia produces reactive oxygen species (ROS) and induces cell damage. Therefore we attempted to investigate the potential of hyperoxia as an anti-tumor treatment in NSCLC cells in this study. Methods: We used oxygen-concentration-adjustable incubators and validated effect of hyperoxia on various lung cancer cell lines in vitro. The effect of hyperoxia on cell proliferation, apoptosis and gene expression was evaluated using MTS assay, flowcytometry and cDNA microarray, respectively. Results: We found that the growth of lung cancer cell lines (A549, NCI-H1975) was inhibited by 50% of hyperoxia in a dose-dependent manner, while that of normal airway epithelial cells (NHBE, BEAS-2B) was not. Two independent pathway analysis using cDNA microarray revealed the activation of NF-kB and AMPK pathways, and the production of nitric oxide and ROS in hyperoxia (50%) treated lung cancer cell lines compared to untreated ones. The combined treatment with ABT-263, Bcl-2 inhibitor, and hyperoxia (50%) induced synergistic growth inhibition and apoptosis in NCI-H1975 and SK-MES-1 cells. Moreover, the combination of ABT-263 and activator of either ROS, NF-kB or AMPK also showed synergistic growth inhibition in those cells. Conclusions: Hyperoxia (50%) showed anti-tumor effect in NSCLC cell lines through the activation of NF-kB and AMPK pathways, and the production of ROS. The effect was augumented in combination with Bcl-2 inhibitor. Hyperoxia may be a treatment option for NSCLC patients. Citation Format: Junko Hamamoto, Hiroyuki Yasuda, Ichiro Nakachi, Michael G. Edwards, Masayoshi Miyawaki, Makoto Nishino, Aoi Kuroda, Tetsuo Tani, Daisuke Arai, Kota Ishioka, Ichiro Kawada, Katsuhiko Naoki, Tomoko Betsuyaku, Kenzo Soejima. Hyperoxia may be a treatment option for NSCLC. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3006. doi:10.1158/1538-7445.AM2015-3006