In summary, the experimental evidence suggests that the activity of the AR in cancer stem cells present in TNBC tumors positively regulates the self-renewal and the expression of markers associated with stemness; however, it is necessary to evaluate the actions of the AR in ER-positive tumors to establish if it has a role in the maintenance of BCSCs, evaluating the expression of stem genes, self-renewal and tumorigenesis. The gene discussed is AR; the disease is cancer.