RUNX2 and breast cancer: Thus, RUNX2 functions as a master mediator during the transformation of epithelial breast cancer cells into osteomimetic cells under the induction of CAF/BMP2, and the expression of BRGs is repressed by the TGF-β/SMAD/RUNX2 signaling pathway but induced by the BMP/SMAD/RUNX2 signaling pathway.