While early innate immune response induction by TLR ligation could reduce leukemia penetrance in the Eμ-RET and E2A–PBX1 transgenic mouse models38, ex vivo Toll-like receptor signaling induction by exposure to lipopolysaccharide triggers transformation of ETV6–RUNX1+ precursor B cells39. This evidence concerns the gene PBX1 and leukemia.