Targeting ALDH2 with Alda-1 to reverse cisplatin resistance in lung adenocarcinoma.
BACKGROUND: Cisplatin resistance remains a major obstacle in lung adenocarcinoma (LUAD) treatment. The role of Aldehyde dehydrogenase 2 (ALDH2), a detoxifying enzyme, in LUAD prognosis and chemoresistance is poorly understood. METHODS: We analyzed ALDH2's prognostic value using clinical cohorts, TCGA, and proteomic data. Cisplatin-resistant cell lines and xenograft models were used to assess the effect of the ALDH2 agonist Alda-1. Molecular mechanisms were investigated via gain/loss-of-function studies. RESULTS: High ALDH2 expression was significantly associated with improved survival in univariate analysis and correlated with a favorable genomic instability profile in LUAD. Pharmacological activation of ALDH2 with Alda-1 restored cisplatin sensitivity in resistant cells and potently enhanced cisplatin's efficacy in vivo. Mechanistically, ALDH2 activation upregulated PKC-ζ, leading to downregulation of the drug efflux pump MDR1. Proteomic analysis further linked low ALDH2 expression to a pro-chemoresistance signature. CONCLUSION: ALDH2 represents a potential prognostic biomarker associated with favorable outcomes in LUAD, particularly in patients receiving chemotherapy. Its activation via Alda-1 overcomes cisplatin resistance by targeting the PKC-ζ/MDR1 axis, presenting a novel therapeutic strategy.