HR and breast carcinoma: In line with the current understanding that CSCs contribute to resistance of cancer cells to chemotherapy [68], we have previously shown that TME Stimulation-enriched CD44+/CD24low/− cells had a survival advantage following doxorubicin treatment (that is employed in the clinic in the treatment of HR+/HER2− breast cancer patients [69]) of HR+/HER2− breast cancer cells [16], over non-stimulated cells.