The study focused on acute lymphoblastic leukaemia (ALL), MOLT-4 and CCFR-CEM (Acute T lymphoblastic leukaemia) and SUP-B15 (Acute B lymphoblastic leukaemia) cell lines as daunorubicin is widely used in the treatment of this leukaemia [27] and the process of lymphoid tumorigenesis often involves alterations to the ataxia-telangiectasia mutated (ATM) gene resulting in ATM deficient cells which are more sensitive to oxidative stress and are likely to undergo altered DNA repair and apoptotic pathways [28]. This evidence concerns the gene ATM and leukemia.