As the refractory CMY cell line had a high percentage of the ALDH-positive “stem-like” cells (Fig. 1b), we investigated the cytotoxicity of BTZ (previously reported to target AML stem cells), and DSF (ALDH inhibitor) using the same panel that includes cell lines with high and low endogenous ALDH activity (Table 1, Fig. 1b). The gene discussed is CASC3; the disease is acute myeloid leukemia.