Clinical significance of Surface Leukemic Stem Cell Markers: CD25 Expression Restricts Prognostic Impact of CD123 in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a clonal disorder of immature blast cells that originates from leukemic stem cells (LSCs). These LSCs are responsible for disease initiation and propagation, and exhibit chemotherapy resistance. Thus, eradication of LSCs is essential for preventing relapse and prolonging patient survival [1]. Cell surface markers, CD25 and CD123 are well-established LSC markers and the expression of each marker is described as an excellent predictor of unfavorable outcome of AML [2,3] However, as the distribution of the expression of CD25 and CD123 within the LSC population appreciably differ from each other, there appears to be a gap of prognostic value between these two markers. Although the combined effect of their expression on clinical outcome has been evaluated [4], little data are available regarding a difference in the prognostic effect between them in patients with AML. Analysis of this issue will provide an important information for the development of LSC targeted therapeutic strategies against AML.?