Roles of myeloperoxidase and the AMPK/PI3K/AKT/eNOS pathway in osimertinib-induced cardiotoxicity: multilevel evidence from disequilibrium analysis, network pharmacology, mendelian randomization, and animal experiments.

Introduction: Osimertinib, a third-generation Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor (EGFR-TKI), is central to first-line therapy for EGFR-mutant Non-Small Cell Lung Cancer (NSCLC), showing improved outcomes; however, its cardiotoxicity raises critical concerns. The incidence, risk factors, and management of this condition remain poorly understood and require further mechanistic exploration. This study aimed to investigate the risk signals, mechanisms, and causal associations of osimertinib-induced cardiotoxicity using multilevel analyses, focusing on myeloperoxidase (MPO) and the AMPK/PI3K/AKT/eNOS pathway. Methods: The study methods included: (1) disproportionality analyses of FAERS and VigiBase (Q1 2016-Q4 2024), (2) network pharmacology for targets/pathways, (3) Mendelian randomization for causal validation, and (4) animal experiments to test the mechanisms. The exposures were osimertinib in real-world data; in animals, the exposures were osimertinib (8.33 mg/kg, i. p.) alone or with inhibitors (ABAH, Compound C, LY294002, L-NAME). The main outcomes and measures were (1) Real-world: CAE incidence/spectrum/risk signals (ROR, PRR, IC; e.g., heart failure, arrhythmias) (2) Molecular: Core targets/pathways (e.g., PI3K/AKT). via network pharmacology and genetically validated targets via Mendelian randomization. (3) Results: Disproportionality analyses showed high signals for cardiac dysfunction (ROR = 16.10, FAERS), cardiotoxicity (ROR = 8.43, FAERS), and long QT syndrome (ROR = 15.85, VigiBase). Network pharmacology identified 111 overlapping targets with core targets in the PI3K/AKT pathway. Mendelian randomization validated nine targets related to PI3K/AKT with causal ties to arrhythmias/heart failure. In animal experiments, osimertinib upregulated MPO, inhibited AMPK/PI3K/AKT/eNOS, and induced cardiac dysfunction, damage, apoptosis, oxidative stress, and inflammation. MPO inhibition attenuated these effects, and co-administration with pathway inhibitors reversed the protective effect. Discussion: Osimertinib induces cardiotoxicity via MPO upregulation, which inhibits the AMPK/PI3K/AKT/eNOS pathway. MPO and related pathways may serve as biomarkers or therapeutic targets, supporting risk monitoring and safety management in osimertinib use.