miR-155 as a potential target of IL-3 signaling in primary AML cells.

miR-155 has emerged as one of the key microRNAs (miRNAs) involved in normal and malignant myelopoiesis, and high expression of this miRNA has been flagged as a strong independent prognostic marker in Acute Myeloid Leukemia (AML). While elevated expression of miR-155 has been associated with FLT3-ITD mutations, other mechanisms which may regulate expression of this miRNA in AML remain largely unknown. Here, we present new evidence that miR-155 may be a prime target of IL-3 signaling in primary AML cells. This finding, together with the increasingly apparent role for miR-155 in oncogenesis, and the upregulation of the IL-3 receptor alpha subunit in AML, lead us to propose this pathway may significantly contribute to the leukemic transformation.