HOXA9 and acute myeloid leukemia: Meis1 was recently shown to directly induce Flt3 expression in murine BM cells together with either Hoxa9 or ND13 or NA10 [43], [44] and we have also shown that high Flt3 expression is sufficient to induce AML transformation in mice using preleukemic BM cells expressing either ND13 or NA10 [43].