AURKA Suppresses Ferroptosis via the KEAP1/NRF2/HO‑1 Axis in EGFR-Mutant Lung Adenocarcinoma.

Abstract

Background: Adenocarcinoma of Lung (LUAD) remains a leading cause of cancer-related deaths across the globe, and patients harboring epidermal growth factor receptor (EGFR) mutations frequently develop resistance to targeted therapies. While aurora kinase A (AURKA) has been implicated in tumorigenesis, its involvement in regulating ferroptosis via the kelch-like ECH-associated protein 1 (KEAP1)/NF-E2-related factor 2 (NRF2)/heme oxygenase 1 (HO‑1) signaling axis in EGFR-mutant LUAD remains poorly understood.

Methods: We analyzed RNA-seq and clinical data from 594 LUAD samples from The Cancer Genome Atlas (TCGA) to explore associations between AURKA expression, EGFR mutation status, and immune cell infiltration. A ferroptosis-focused random forest algorithm was constructed to predict EGFR-mutant cases. In vitro, AURKA was silenced by siRNA in EGFR-mutant NCI-H1975 cells; subsequent assays included transcriptome profiling, measurements of intracellular Fe²⁺, malondialdehyde (MDA), glutathione (GSH), mitochondrial reactive oxygen species (ROS) levels, and ultrastructural examination by electron microscopy. Protein levels of NRF2, HO‑1, solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), and KEAP1 were assessed via western blot.

Results: The ferroptosis gene-based random forest model distinguished EGFR-mutant LUAD with an area under the curve (AUC) of 0.84. Clinically, high AURKA expression was significantly associated with EGFR wild-type status (p = 0.035), reduced overall survival (p = 0.011), increased M1 macrophage infiltration, and decreased CD4⁺ T-cell infiltration. AURKA knockdown triggered hallmark features of ferroptosis-iron overload (p < 0.001), elevated MDA levels (p < 0.01), increased lipid peroxidation (p < 0.05), heightened mitochondrial ROS (p < 0.05), reduced mitochondrial membrane potential, GSH depletion (p < 0.05), and disruption of mitochondrial cristae. Mechanistically, loss of AURKA decreased KEAP1 (p < 0.01) and enhanced NRF2 (p < 0.001) and HO-1 (p < 0.01) and NRF2 nuclear translocation, while downregulating SLC7A11 (p < 0.05) and GPX4 (p < 0.01). Cell cycle analysis revealed G1-phase arrest (p < 0.001).

Conclusions: Our findings demonstrate that AURKA promotes ferroptosis resistance in EGFR-mutant LUAD by modulating the KEAP1/NRF2/HO-1 axis. Notably, this effect was validated in the gefitinib-resistant EGFR T790M-mutant NCI-H1975 cell model. Our results highlight AURKA as a potential therapeutic target for overcoming epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance and suggest that disrupting the AURKA/KEAP1/NRF2/HO‑1 pathway may offer a novel strategy for treating EGFR-mutant LUAD.