Breast tumor cells that portray complete E or M states show less self-renewal capacity or cell plasticity, respectively 58, while those with a hybrid phenotype are essential for tumorigenicity in basal breast cancer cells, have higher plasticity, stemness, mammosphere-forming, and self-renewal capacities, and produce progenies of drug-resistant ALDH1+ cells 58,59. The gene discussed is ALDH1A1; the disease is breast cancer.