TLR4 and acute lymphoblastic leukemia: In other hematological cancers, such as acute myeloid leukemia (AML), the mRNA expression levels of TLR2 and TLR4, but not of TLR9, were increased, contrary to what was observed in ALL [37], and expression of TLR7 and 9 was decreased in chronic myeloid leukemia (CML) [38].