Involvement of MicroRNA in T-Cell Differentiation and Malignancy.

MicroRNAs are 19-22 nucleotide RNAs involved in such important processes as development, proliferation, differentiation and apoptosis. Different miRNAs are uniquely expressed in lymphoid T cells, and play a role indevelopment and differentiation of various subtypes by targeting their target genes. Recent studies have shown that aberrant miRNA expression may be involved in T cell leukemogenesis and lymphogenesis, and may function as tumor suppressor (such as miR-451, miR-31, miR-150, and miR-29a) or oncogene (e.g. miR-222, miR-223, miR-17-92, miR-155). MiRNAs can be used as new biomarkers for prognosis and diagnosis or as an index of disease severity in T-cell leukemia and lymphoma. This article presents a review of studies in recent years on the role of miRNAs in T-cell development and their aberrant expression in pathogenesis of T-cell leukemia and lymphoma. Characterizing miRNAs can help recognize their role as new important molecules with prognostic and therapeutic applications.