Jagged-1: a new promising factor associated with favorable prognosis in patients with acute myeloid leukemia.

In this study Jagged-1 and Dll-1 surface expression as well as Notch-1 receptor intracellular domain (Notch-1-IC) expression were assessed by multi-color flow cytometry in leukemic blasts obtained from 88 patients with acute myeloid leukemia (AML). CD34+peripheral blood stem cells (PBSCs) were used as a control. The median expression of Jagged-1 and Dll-1 was significantly higher in AML blasts than in PBSCs (p=0.001 and p=0.002, respectively). Higher expression of Notch-1-IC was detected in patients with poor-risk karyotype as compared to good- and intermediate-risk groups (p=0.035). In our study, poor-risk cytogenetics and low (<median) expression of Jagged-1 were the only factors associated with significantly shorter overall survival in intensively treated patients according to multivariate analysis. In conclusion, high Jagged-1 surface level in leukemic cells is an independent favorable prognostic factor in patients with AML. To our knowledge, this is the first study evaluating the prognostic role of Notch-1-IC in AML blasts.