MiRNAs are short ncRNAs which act as tumor suppressor (i.e., miR-15, miR-16, let-7, and miR-127) or oncogene (i.e., miR-155, miR-17-92, miR-21, miR-125b, miR-93, miR-143-p3, miR-196b, and miR-223) in leukemia.
Expression of miR-128b and miR-223-both are leukemia specific-changed in parallel with percentage of bone marrow blasts in remission and during relapse.
Genetic depletion of miR-223 decreased the leukemia initiating cell (LIC) frequency in a myelomonocytic AML mouse model, but it was not mandatory for rapid-onset AML.
In this context, we recently reported a link between the differentiation block of leukemia and the epigenetic silencing of the microRNA-223 gene by the AML1/ETO oncoprotein, the product of the t(8;21) the commonest AML-associated chromosomal translocation.