biostudies-literatureChen MFoundation of Social Development in Jiangsu—Clinical Frontier TechnologyNatural Science Foundation of Jiangsu Province551-560https://www.ebi.ac.uk/biostudies/studies/S-EPMC7350557biostudies-literatureUnknown41(5)The bone marrow has been long known to host a unique environment amenable to colonization by metastasizing tumor cells. Yet, the underlying molecular interactions which give rise to the high incidence of bone metastasis (BM) in breast cancer patients have long remained uncharacterized. In our study, in vitro and in vivo assays demonstrated that Brachyury (Bry) could promote breast cancer BM. Bry drives epithelial-mesenchymal transition (EMT) and promotes breast cancer aggressiveness. As an EMT driver, SOX5 involves in breast cancer metastasis and the specific function in BM. Chromatin immunoprecipitation (ChIP) assays revealed SOX5 is a direct downstream target gene of Bry. ChIP analysis and reporter assays identified two Bry-binding motifs; one consistent with the classic conserved bindinCarcinogenesisTransactivation of SOX5 by Brachyury promotes breast cancer bone metastasis.PMC7350557BE2017661BK20151196Shen MHe CShen JLi SHuang YChen MCheng RWang DZou SZou TYan XZhou JfalseTransactivation of SOX5 by Brachyury promotes breast cancer bone metastasis.The bone marrow has been long known to host a unique environment amenable to colonization by metastasizing tumor cells. Yet, the underlying molecular interactions which give rise to the high incidence of bone metastasis (BM) in breast cancer patients have long remained uncharacterized. In our study, in vitro and in vivo assays demonstrated that Brachyury (Bry) could promote breast cancer BM. Bry drives epithelial-mesenchymal transition (EMT) and promotes breast cancer aggressiveness. As an EMT driver, SOX5 involves in breast cancer metastasis and the specific function in BM. Chromatin immunoprecipitation (ChIP) assays revealed SOX5 is a direct downstream target gene of Bry. ChIP analysis and reporter assays identified two Bry-binding motifs; one consistent with the classic conserved bindin2020-01-01T00:00:00Z2020 Jul2025-06-01T02:54:00.21Z2025-06-01T02:54:00.21ZS-EPMC73505573171360410.1093/carcin/bgz142