Hence, our results suggested that ATF-3 plays a role in proliferation and invasion of bone metastatic breast cancer cells in vitro and we identified for the first time that Runx2 is a target gene of ATF-3 in MDA-MB231 cell line.
These initial observations have prompted further analysis of Runx2 function in mammary epithelial cells and recent findings have demonstrated that Runx2 does indeed contribute to the ability of metastatic breast cancer cell lines to form osteolytic bone lesions.
Our findings suggest that fidelity of Runx2 intranuclear organization is necessary for expression of target genes that mediate the osteolytic activity of metastatic breast cancer cells.
Osteoblast-related transcription factors Runx2 (Cbfa1/AML3) and MSX2 mediate the expression of bone sialoprotein in human metastatic breast cancer cells.