CD44 and neoplasm: This is noteworthybecause ALDH + cells, known for their tumor-initiating capacity, typically increase in the presence of cytotoxicor cytostatic stressors, such as those induced by tamoxifen or ROS. This effectis not limited to ALDH, as reports also suggest the increase of CD44+/CD24–cells in case of drug-related cytotoxicity and tumor cell death. It is interesting, however, that we observethe converse (i.e., high proliferation correlating with low ALDH +population) only for E-CSCs.