We define the aggressive potential of BrC cells as follows: to present a cancer stem cell-like phenotype CD44+ CD24−/low; to present the epithelial-to-mesenchymal transition (EMT), which is characterized by positivity to vimentin (mesenchymal marker) and negativity to E-cadherin (epithelial marker), and to be invasive in transwell assays. Here, CD44 is linked to cancer.