Genes that mediate breast cancer metastasis to lung

By means of in vivo selection, transcriptomic analysis, functional verification and clinical validation, here we identify a set of genes that marks and mediates breast cancer metastasis to the lungs. Some of these genes serve dual functions, providing growth advantages both in the primary tumour and in the lung microenvironment. Others contribute to aggressive growth selectively in the lung. Many encode extracellular proteins and are of previously unknown relevance to cancer metastasis. Much research in breast cancer is aimed at identifying tumour subtypes that influence clinical outcome. One such study has identified a series of genes that mediate breast carcinoma metastasis to the lung but not other organs. Poor-prognosis patients with this gene signature fare much worse than other poor-prognosis patients. The data suggest that a subset of these genes mediates growth of the primary breast tumours and of the metastases in the lung, while a second subset provides virulence at the metastatic site without enhancing primary tumour growth. These genes are potential targets for administered inhibitors.