A549 cell

The A549/TaxR cells were purchased from KeyGen Biotech (Nanjing, Jiangsu, China), while A549 cells were purchased from the Cell Bank of Chinese Academy of Sciences (Shanghai, China). Both A549 and A549/TaxR cells were cultivated by RPMI-1640 medium containing 10% FBS and 100 μg/mL of penicillin-streptomycin. To maintain resistance, taxol (70 nM) was added into the medium with A549/TaxR cells, and all cells were cultivated in 5% CO₂ under 37 °C conditions.

Monomethoxy PEG (mPEG, molecular weight Mn=2000 Da), ε-caprolactone (ε-CL) and dopamine hydrochloride were purchased from Macklin Biochemical Co. Ltd. (Shanghai, China). Stannous octoate (Sn(Oct)₂) was obtained from Sigma-Aldrich Trading Co. Ltd. (USA), and paclitaxel from Meilun Biological Technology Co. Ltd. (Dalian, China). B. infantis (GIMI.207) was provided by the Strains Preservation Center of Guangzhou Institute of Microbiology (Guangdong, China), and incubated anaerobically on agar plates at 37°C for 48 hours. A549 cells were purchased from the Cell Bank of Chinese Academy of Sciences (Shanghai, China). Male nude mice weighting 16–18 g (6 weeks of age) were supplied by Tengxin Biological Technology Co. Ltd. (Chongqing, China). All animal experimental procedures were approved by the Ethics and Science Committee of the Animal Care and Treatment Committee of Southwest Medical University and followed the Chinese National Guidelines (GB/T 35892-20181). The mice were housed in specific pathogen-free conditions at 24°C and relative humidity of 50–60% under a 12h-light/12h-dark schedule, with ad libitum access to standard rodent food and tap water. All mice were healthy and had no infection during the experimental period.

PQ and the adenoviral (AD) system, including plasmids containing the predesigned human Nrf2 gene and fetal bovine serum (FBS), were purchased from Sigma-Aldrich; Merck KGaA (Darmstadt, Germany). RPMI-1640 medium was obtained from Gibco; Thermo Fisher Scientific, Inc. (Waltham MA, USA). A549 cells were purchased from the Type Culture Collection of the Chinese Academy of Sciences (Shanghai, China). The Cell Counting Kit-8 (CCK-8) was obtained from Dojindo Molecular Technologies, Inc. (Kumamoto, Japan). Lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) detection kits were supplied by Nanjing Jiancheng Bioengineering Institute (Nanjing, China). Antibodies against Nrf2 and P-gp were obtained from Abcam (Cambridge, UK). GFP was purchased from Thermo Fisher Scientific, Inc. CsA (cat. no. 59865-13-3) was purchased from Sigma-Aldrich; Merck, KGaA.

Normal human bronchial epithelioid cells (16HBE cells) and NSCLC cells (A549 cells and H1299 cells) were obtained from the China Center for Type Culture Collection (Wuhan, China). H1299 cells are positive for keratin and vimentin but are negative for neurofilament triplet protein. The cells harbor a homozygous partial deletion in the p53 protein, resulting in the lack of p53 protein expression. Additionally, H1299 cells are capable of producing neuromedin B. Cells were cultured in 89% Dulbecco's modified Eagle medium (DMEM: Invitrogen) at 37°C. The siRNAs of circCPA4 (si‐circCPA4) and ASCT2 (si‐ASCT2), short hairpin RNA targeting circCPA4 (sh‐circCPA4) and negative controls, miR‐145‐5p mimic, miR‐145‐5p inhibitor and negative controls (mimic NC and inhibitor NC), and pcDNA‐ASCT2 and control (pcDNA) were purchased from GenePharma. Cell transfection was executed following the instructions of lipofectamine 2000 (Invitrogen).