ABCA2 and leukemia: This co-localization indicates a direct sequestration of this antineoplastic drug into endo- and/or lysosomes.171 On the other hand, the susceptibility of ABCA3-overexpressing CCRF-CEM leukemia cells to the antineoplastic agents cytarabine, methotrexate (Figure 1), vincristine, but also the anti-inflammatory drug dexamethasone, was reduced compared to their parental counterparts.242 Taken together, ABCA2 and ABCA3 are contributors to MDR, and the number of potential ABCA2 and ABCA3 substrates may be even higher than currently suggested.