miR‐941 in extracellular vesicles confers anlotinib resistance via Keap1/Nrf2 axis and represents a therapeutic target in non‐small cell lung cancer

BACKGROUND: Anlotinib is a multitargeted tyrosine kinase inhibitor for the treatment of advanced non-small cell lung cancer (NSCLC), though its therapeutic efficacy is constrained by acquired resistance. Although elevated extracellular vesicle (EV)-derived miR-941 correlates with anlotinib resistance, its functional role remains unexplored. Here, we provide evidence that EV-delivered miR-941 mediates this resistant phenotype. METHODS: Functional experiments (gain- and loss-of-function) in A549 and H1299 cells assessed viability, apoptosis and migration. The miR-941/Keap1 interaction was validated using dual-luciferase assays. In vivo resistance was evaluated using wild-type and Keap1 3'UTR-mutant xenograft models. Clinical relevance and survival outcomes were analysed in tumour tissues from anlotinib-treated patients. RESULTS: EV-derived miR-941 was significantly upregulated in anlotinib-resistant patients. Mechanistically, miR-941 directly targeted the Keap1 3'UTR, suppressing Keap1 protein and activating the Nrf2 signalling pathway. This axis inhibited apoptosis, upregulated anti-apoptotic proteins (Bcl-2, Mcl-1), and promoted malignant phenotypes in vitro. Crucially, in vivo anlotinib resistance induced by miR-941 overexpression was completely abrogated by mutating the Keap1 binding site. Clinical samples confirmed elevated miR-941 and a molecular signature consistent with Keap1 downregulation and Nrf2 activation in resistant tumours. Furthermore, high expression of miR-941 was strongly associated with shorter progression-free survival and overall survival. CONCLUSION: In this study, we identified EV-derived miR-941 as a key driver of anlotinib resistance via the Keap1/Nrf2 pathway. It represents a promising non-invasive predictive biomarker and serves as a candidate therapy target for overcoming drug-resistant NSCLC. KEY POINTS: EV-derived miR-941 as a key driver of anlotinib resistance via the Keap1/Nrf2 pathway represent a promising non-invasive predictive biomarker and a potential therapeutic target for overcoming resistance in NSCLC.