SLC25A11-mediated reprogramming of mitochondrial redox state and lipid peroxidation confers NRF2-dependent ferroptosis resistance in biliary tract cancer

BACKGROUND: Biliary tract cancer is a group of highly heterogeneous and metastatic malignancies of the biliary tract. Current clinical treatment strategies and diagnostic methods need further improvement to effectively manage this disease. METHODS: We performed multiomics integrative and in silico analyses of selected SLC25 family members. Cell models with SLC25A11 overexpression or knockdown can be used for various biological function assays and cell imaging. Animal models and clinical specimens can be used to evaluate prognosis and treatment. RESULTS: SLC25A11 inhibition significantly reduced cell migration and proliferation both in vitro and in vivo. In addition, loss of SLC25A11 leads to accumulation of TCA-related metabolites, alters mitochondrial homeostasis, and reduces mitochondrial membrane potential. In addition, we confirmed that lipid peroxidation and lipid ROS aggregation in mitochondria by SLC25A11-knockdown model. Based on our RNA sequencing data, inhibition of SLC25A11 reduces NRF2 expression and translocation, resulting in loss of interaction affinity with the ferroptosis suppressor FSP1 and subsequent reactivation of the ferroptosis machinery. We also showed that low levels of SLC25A11 and knockdown models can activate lipid peroxidation and related molecules ACSL4, LPCAT3, and PEBP1, further inducing ferroptosis. Furthermore, recruitment of ferrostatin-1 (Fer-1) antagonizes the ferroptosis state by reducing lipid peroxidation and blocking the expression levels of these related molecules. CONCLUSIONS: Bringing all the evidence together, we added several important insights between ferroptosis and biliary tract cancer. We raised that SLC25A11 will serve as a novel prognostic factor and treatment strategy for biliary tract cancer.