CD44 and breast cancer: MMPs, ADAMs, HES1/2, HEY1, c-Myc, CD44, EpCAM and Vimentin (downregulation of E-cadherin) engage in survival, stemness, EMT, invasion, ECM degradation/remodeling, angiogenesis, intravasation/extravasation, and metastatic colonization in breast cancer.