Stem cell therapy: A paradigm shift in breast cancer treatment

Figure 1 Breast cancer stem cells: Origin and outcome. Breast cancer stem cells (BCSCs) can arise from normal mammary stem cells which have undergone mutations or from mutated progenitor cells or dedifferentiated cells, which comprise the mammary tissue. The subpopulation of BCSCs can be identified based on the altered expression of cell surface markers such as CD44 and CD24 as well as higher activity of the enzyme aldehyde dehydrogenase (ALDH1). These BCSCs when transplanted in SCID/nude mice have the ability to form mammospheres, which are three-dimensional spheres generated through the clonal expansion of single cancer stem cells. These cancerous stem cells have been implicated in the poor outcomes associated with aggressive breast cancer subtypes.