ALDH1A3 is highly expressed in therapy-resistant cancer cell subpopulations and has been shown to confer resistance to several chemotherapeutic agents, including doxorubicin, paclitaxel, docetaxel, temozolomide, 5-fluorouracil, oxaliplatin, and cisplatin in multiple cancers, such as colorectal cancer [64,67], lung adenocarcinoma [68], melanoma [37], malignant pleural mesothelioma [69,70], gastric cancer [51], prostate cancer [71], osteosarcoma [56], colon cancer [72], and human embryonal carcinoma cells [73]. The gene discussed is ALDH1A3; the disease is osteosarcoma.