Metastasis-associated protein 1 (MTA1) is transferred by exosomes and contributes to the regulation of hypoxia and estrogen signaling in breast cancer cells

This is the first report showing that BC exosomes contain MTA1 and can transfer it to other cells resulting in changes to hypoxia and estrogen receptor signaling in the tumor microenvironment. These results, collectively, provide evidence suggesting that exosome-mediated transfer of MTA1 contributes to BC progression by modifying cellular responses to important signaling pathways and that exosome-MTA1 may be developed as a biomarker and therapeutic target for BC.