ATP synthasome contributes to efficient energy flux in malignant breast cancer

Background: This study investigates the metabolic alterations associated with breast cancer progression and elucidates the underlying mechanisms. Adenine nucleotide translocase 2 (ANT2), a mitochondrial protein essential for cellular energy metabolism, facilitates the exchange of ADP and ATP across the inner mitochondrial membrane. The role of ANT2, particularly its interaction with the ATP synthasome, in breast cancer metastasis remains poorly understood. Methods: We analyzed ANT2 in breast cancer using genetic and clinical methods, validating its expression in human tissues. Gene enrichment studies and functional assays assessed ANT2's role in mitochondrial function and cancer metabolism. Knockdown experiments and pharmacogenomic screening evaluated ANT2's impact on metastasis and identified potential inhibitors in 3D cultures and orthotopic mouse models. Results: ANT2 was significantly overexpressed in metastatic breast cancer, correlating with reduced survival. Knockdown of ANT2 impaired cell migration and invasion, reduced ATP production, and diminished oxidative phosphorylation (OXPHOS) activity in MCF7-F4 cells. In vivo, siRNA-mediated ANT2 silencing in JC-M3 cells decreased tumor growth and lung metastases in mice. Pharmacogenomic analysis identified cymarin as an ANT2 inhibitor, reducing spheroid formation in 3D cultures and tumor burden in vivo, alongside downregulation of epithelial-to-mesenchymal transition (EMT) and OXPHOS markers. ANT2 colocalized with ATP5B, forming an ATP synthasome that enhanced energy flux in hyperinvasive cells. Conclusions: ANT2 drives breast cancer metastasis by enhancing mitochondrial energy production via the ATP synthasome. Its inhibition, particularly with cymarin, disrupts tumor bioenergetics and metastatic potential, positioning ANT2 as a promising therapeutic target.