Pfeffer S, Voinnet O
IBMP-CNRS, rue du Général Zimmer, Strasbourg, France.
Oncogene. 2006 Oct 9;25(46):6211-9. doi: 10.1038/sj.onc.1209915.
Viruses represent one of the main factors that cause normal cells to proliferate and to become malignant: up to 15% of all human cancers are associated with single or multiple virus infections, and several viruses have been recognized as causal agents of specific types of cancer. Viruses have evolved many strategies to prevent infected cells from becoming apoptotic and to evade the innate and adaptive immune responses of their hosts. The recent discovery that Epstein-Barr virus and other herpesviruses produce their own sets of micro (mi)RNAs brings an additional layer of complexity in this ongoing host-virus arms race and changes our initial views of the antiviral roles of RNA silencing in plants and insects. It seems that, rather than being inhibited by this process, many mammalian viruses can usurp or divert the host RNA silencing machinery to their advantage. Viral-encoded miRNAs can act both in cis, to ensure accurate expression of viral genomes, and in trans, to modify the expression of host transcripts. Here, we review the current knowledge on viral miRNAs and discuss how mammalian viruses can also perturb host miRNA expression. Those recent findings provide new insights into the role of viruses and miRNAs in cancer development.
所有人类癌症中，高达15%与单一或多种病毒感染有关，并且几种病毒已被确认为特定类型癌症的致病因子。病毒已进化出多种策略来防止受感染细胞发生凋亡，并逃避宿主的先天性和适应性免疫反应。最近发现，爱泼斯坦-巴尔病毒和其他疱疹病毒会产生自己的一组微小（mi）RNA，这在这场持续的宿主-病毒军备竞赛中增加了一层复杂性，并改变了我们对RNA沉默在植物和昆虫中抗病毒作用的最初看法。看起来，许多哺乳动物病毒非但没有被这一过程抑制，反而能够篡夺或挪用宿主的RNA沉默机制以使其自身受益。病毒编码的miRNA既能顺式作用，以确保病毒基因组的准确表达，也能反式作用，以改变宿主转录本的表达。在此，我们综述了关于病毒miRNA的现有知识，并讨论了哺乳动物病毒如何也能干扰宿主miRNA的表达。这些最新发现为病毒和miRNA在癌症发展中的作用提供了新的见解。
