Deregulation of microRNAs in myelodysplastic syndrome.

Myelodysplastic syndromes (MDSs) consist of a family of hematopoietic stem cell (HSC) disorders characterized by ineffective differentiation of hematopoietic progenitors, bone marrow dysplasia, genetic instability and a propensity to develop acute myeloid leukemia. The development of MDS is poorly understood and therefore, effective treatment options are limited. Recent progress has been made in identifying altered signaling pathways and understanding the HSC defects, which are thought to contribute to the pathogenesis of MDS. Several of these findings have implicated aberrant expression and function of microRNAs (miRNAs). Unique miRNA expression patterns have been identified in MDS patients and modeled in mice to recapitulate features of MDS. Here, we review miRNA expression profiles identified in MDS patients, and describe the association of miRNA expression with MDS subtypes and disease outcome, clinical implications of miRNAs in MDS and deregulation of miRNAs in mouse model systems of MDS.