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Abstract Lung cancer, with non‐small cell lung cancer (NSCLC) being the main subtype, is the leading cause of cancer death worldwide, which is mainly due to the cancer metastasis. Glutathione peroxidase 2 (GPX2), an antioxidant enzyme, is involved in tumor progression and metastasis. Nevertheless, the role of GPX2 in NSCLC metastasis has not been clarified. In this study, we found that GPX2 expression was elevated in NSCLC tissues and high GPX2 expression was correlated with poor prognosis in patients with NSCLC. In addtion, GPX2 expression was related to the patient's clinicopathological features, including lymph node metastasis, tumor size, and TNM stage. Overexpression of GPX2 promoted epithelial–mesenchymal transition (EMT), migration, and invasion of NSCLC cells in vitro. Knockdown of GPX2 showed the opposite effects in vitro and inhibited the metastasis of NSCLC cells in nude mice. Furthermore, GPX2 reduced reactive oxygen species (ROS) accumulation and activated the PI3K/AKT/mTOR/Snail signaling axis. Therefore, our results indicate that GPX2 promotes EMT and metastasis of NSCLC cells by activating the PI3K/AKT/mTOR/Snail signaling axis via the removal of ROS. GPX2 may be an effective diagnostic and prognostic biomarker for NSCLC.

This study focuses on toughness enhancement of basalt fibre-reinforced shotcrete (BFRS). Four-point bending experiments of underground shooting and curing beams combined with a roadway-supporting deformation monitoring test were conducted. The flexural performance was analysed based on the toughness standards, namely, DBV-1998, JSCE SF-4, and nuclear magnetic resonance (NMR) pore testing. The results demonstrate that, given a basalt fibre (BF) dosage of 0–7.5 kg/m3, 18 mm BF can significantly increase the residual stress under the same deformation, rather than the peak values of the flexural strength. Meanwhile, the trend in the flexural toughness increases to a peak at a dosage of 3–4.5 kg/m3, followed by a declining curve. The pores from an NMR test can be divided into three types based on size: (1) closed pores, R 5 μm. The connected pores are detrimental, playing a crucial role in the shotcrete performance. Furthermore, the deformations of the roadway walls are significantly restrained by the BFRS, and the 80-day convergences are approximately 2 mm, which is only 25% of the control. Finally, the comprehensive results indicate that a dosage range of 3–4.5 kg/m3 can demonstrate reasonable beneficial effects for the BFRS performance.