Guil Sònia, Esteller Manel
Institut d'Investigacio Biomedica de Bellvitge, 08907 L'Hospitalet, Barcelona, Catalonia, Spain.
Int J Biochem Cell Biol. 2009 Jan;41(1):87-95. doi: 10.1016/j.biocel.2008.09.005. Epub 2008 Sep 13.
Our current knowledge of the deregulation that occurs during the onset and progression of cancer and other diseases leads us 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, and 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 the occurrence of cancer. In this review we discuss microRNA genes that are epigenetically modified in cancer cells, and the role that microRNAs themselves can have as chromatin modifiers.
我们目前对癌症及其他疾病发生和发展过程中出现的失调现象的了解，使我们认识到基因和表观遗传改变均处于病理状态的核心。表观遗传格局包括多种共价修饰，这些修饰不仅影响DNA的甲基化状态，还影响组蛋白的翻译后修饰，并决定染色质的结构特征，最终控制细胞的转录结果以适应发育、增殖或环境需求。微小RNA是一类小的非编码RNA，可调节互补信使RNA的表达，并在包括增殖、分化和凋亡在内的众多细胞过程中作为关键调控因子发挥作用。在过去几年中，越来越多的证据表明，大量微小RNA基因会发生表观遗传改变，导致癌症发生时出现异常的表达模式。在本综述中，我们讨论了在癌细胞中发生表观遗传修饰的微小RNA基因，以及微小RNA自身作为染色质修饰剂可能发挥的作用。
