HOXB7 and breast carcinoma: HOXB7, in particular, known to be dependent on stromal (extracellular matrix) signaling, is transcriptionally upregulated in breast cancers metastatic to bone (relative to primary tumors), and is thought to play a role in promoting angiogenesis, growth factor-independent proliferation and DNA double-strand break repair, conferring breast cancer resistance to the genome destabilizing effects of DNA damage [64].