HLF and acute lymphoblastic leukemia: Retroviral insertions at the Zfp521 locus also promote the formation of B‐cell acute lymphoblastic leukemia (B‐ALL) in mice expressing the chimaeric oncogenic fusion protein E2A‐hepatic leukemia factor (E2A‐HLF), and ZNF521 overexpression is found in patients with translocations generating E2A‐HLF fusion proteins (Yamasaki et al., 2010).