CD44 and neoplasm: Afterwards, an ex vivo 3D culture system of TNBC PDX primary tumor cells identified clone LA1, an epidermal growth factor receptor (EGFR) monoclonal antibody as a CD44 blockade antibody and the tumor suppressor microRNA-30c as effective inhibitors of circulating cancer stem cell (CSC) cluster formation in vitro and lung metastasis of TNBC in vivo [33].