As DEAB was shown to most potently inhibit ALDH1A1, followed by ALDH2, ALDH1A2, ALDH1B1, ALDH1A3 and ALDH5A1 [54], further studies will be required to determine the specific involvement of individual ALDH isoenzyme in ALDH-mediated resistance to 4-HCPA in NB. The gene discussed is ALDH2; the disease is neuroblastoma.