PIK3R1 and acute myeloid leukemia: Second, the PIK3R1 level was significantly lower in FLT3-ITD+AML patients with the higher miR-155-5p level compared to FLT3-ITD-AML (Figure 7B), and the expression of miR-155-5p and the PIK3R1 were negatively correlated (Figure 7C).