LGALS9 and acute myeloid leukemia: It has recently become evident that acute myeloid leukemia (AML) cells, originating from self-renewing myeloid haematopoietic precursors, operate an immunosuppressive pathway which includes facilitation of exocytosis of the T cell immunoglobulin and mucin domain containing protein 3 (Tim-3) and its natural ligand, galectin-9 (2–4).