DNA methylomes, histone codes and miRNAs: Tying it all together

Our current knowledge Of the deregulation that occurs during the onset and progression of cancer and other diseases leads LIS to recognize both genetic and epigenetic alterations as being at the core of the pathological state. The epigenetic landscape includes a variety of covalent modifications that affect the methylation status of DNA but also the post-translational modifications of histones, are determines the structural features of chromatin that Ultimately control the transcriptional outcome of the cell to accommodate developmental, proliferative or environmental requirements. MicroRNAs are small non-coding RNAs that regulate the expression of complementary messenger RNAs and function as key controllers in a myriad of cellular processes, including proliferation, differentiation and apoptosis. In the last few years, increasing evidence has indicated that a Substantial number of microRNA genes are subjected to epigenetic alterations, resulting in aberrant patterns of expression Upon file occurrence of cancer. In this review we discuss microRNA Pries that are epigenetically modified in cancer cells. and the role that microRNAs themselves can have as chromatin modifiers. (C) 2008 Elsevier Ltd. All rights reserved.