CD44 and acute lymphoblastic leukemia: Specifically, several studies have highlighted the clinical significance of CD44 as a tumor-initiating marker of chronic (CML) [248] and acute (AML) myeloid leukemias [249], and CD44 expression levels have also been associated with LIC activity in murine models of T-ALL, were a link between NOTCH signaling and CD44 expression was observed [250].