Galimberti et al., studied ABCG2 mRNA by real-time PCR in 52 AML samples, finding intermediate levels in 48.2% and high levels in 27.6%, and reporting a significant correlation between ABCB1 and ABCG2 values (r = 0.91, p = 0.0002). Here, ABCG2 is linked to acute myeloid leukemia.