microRNA in Malignant Lymphoma.

microRNAs (miRNAs) are noncoding regulatory RNAs usually consisting of 20-24 nucleotides. During the past decade, increases and decreases in miRNA expression have been shown to associate with various types of diseases, including cancer. Over 4500 miRNAs have been identified in humans, and it is known that nearly all human protein-encoding genes can be controlled by miRNAs in both healthy and malignant cells. Detailed genome-wide miRNA expression analysis has been performed in various malignant lymphoma subtypes, and these analyses have led to the discovery of subtype-specific miRNA alterations. In this chapter, I describe several key miRNAs and their targets in distinct malignant lymphoma subsets and their roles in their pathogenesis, studies of which will lead new therapeutic strategies against aggressive lymphomas.