微小RNA与DNA修复基因的关闭相关联.doc

MicroRNA Linked To Shut-Down Of DNA-Repair Genes微小RNA与DNA修复基因的关闭相关联New research shows for the first time that molecules called microRNA can silence genes that protect the genome from cancer-causing mutations. 新的研究首次显示了微小RNA的能够沉默基因，从而保护致癌突变的基因组。The study, led by researchers at the Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, shows that microRNA-155 (miR-155) can inhibit the activity of genes that normally correct the damage when the wrong bases are paired in DNA. 此项研究由俄亥俄州立大学综合癌症中心－Arthur G. James肿瘤医院和Richard J. Solove研究所研究人员所主持，结果表明，微小RNA - 155（miR- 155）能够抑制某些基因的活性，这些基因通常能修复错误DNA配对所致的损伤。The loss or silencing of these genes, which are called mismatch repair genes, causes inherited cancer-susceptibility syndromes and contributes to the progression of colorectal, uterine, ovarian and other cancers. 这些基因的丢失或者沉默被称为错配修复基因，导致遗传性癌症易感综合征，并促进大肠癌、子宫癌、卵巢癌和其他癌症的恶化。This is the first evidence that deregulation of microRNAs can cause genomic instability, a characteristic of cancer cells, says principal investigator Dr. Carlo M. Croce, professor of molecular virology, immunology and medical genetics, and director of Ohio States Human Cancer Genetics program. “这是第一个证据表明，microRNA的失调可能导致基因组不稳定，这是癌症细胞的一个特点，”主要研究员Carlo M. Croce医生，分子病毒学、免疫学和医学遗传学教授，同时是美国俄亥俄州立的人类癌症遗传学主任。We discovered that miR-155 targets and downregulates mismatch repair genes and that overexpression of miR-155 results in an increase in genomic alterations that contribute to cancer pathogenesis, he says. “我们发现，miR-155主要作用和下调错配修复基因，miR – 155高表达引起基因组改变的增加，这促进癌症的发生，”他说。The study was published recently in the Proceedings of the National Academy of Sciences and shows the following: 这项研究发表在最新一期的美国国家科学院院刊（PNAS），显示如下：Overexpression of miR-155 reduced the expression of the human mismatch repair genes MLH1, MSH2 and MSH6 by 72 percent, 42 percent and 69 percent, respectively, in a colorectal cancer cell line.在一个大肠癌细胞株中，过表达miR－155表达分别