Cancer stem cells: perspectives of new therapeutical approaches for breast cancer.

Currently stem cells are hypothesized to play a central role in the origin, spread and resistance to treatment of breast cancer. Common anticancer therapy is effective but transient, with tumor relapse and metastatic disease often occurring. For therapy to be more effective, debulking of differentiated tumors must occur followed by targeting of the remaining surviving often quiescent tumor stem cells. New therapeutics aimed at cancer stem cells are achieved through non immunological and immunological methods. The former include elective ABC drug transporters or the heat shock protein 90 inhibition, targeting the self-renewal signalling pathways or the EMT program, differentiation therapy, or other interventions to eliminate BrCSCs. The latter include targeting specific antigens expressed on BrCSCs, dendritic cells (DCs) based vaccination and blockers of the extrinsic signals at CSC niche. Here all these novel approaches related to breast cancer stem cells are described.