FLT3 and acute leukemia: While myeloproliferation induced by FLT3-ITD (FLT3ITD/ITD; Cre−) and FLT3-ITD-induced acute leukemia (FLT3ITD/ITD; Mx+) revealed a prominent Gr-1/CD11b high-expressing cell population, deletion of Llgl1 resulted in abrogation of Gr-1 expression (Gr-1hi expression: 3.7392 ± 0.5731 × 105 BMC in FLT3ITD/ITD; Llgl1+/+; Mx+ versus 0.9182 ± 0.4400 × 105 BMC in FLT3ITD/ITD; Llgl1−/−; Mx+; p < 0.0001) (Fig. 4A, B).