医学遗传学：遗传与肿瘤(癌症,家族性).ppt

Cancer Genetics and Genomics ZHANG Xian-Ning, PhD E-mail: zhangxianning@ Tel Office: A713,Reseach Building 2008/10 Cancer After more than three decades, the War on Cancer, declared by President Nixon in 1971 with the enactment of the National Cancer Act, is still going on in this country. The Question is: Are we winning the war? We Fought Cancer…And Cancer Won.After billions spent on research and decades of hit-or-miss treatments, its time to rethink the war on cancer. …In 2008, cancer will take the lives of about 230,000 more Americans—69 percent more—than it did in 1971… Four decades into the war on cancer, conquest is not on the horizon. As a somber statement on the NCI Web site says, the biology of the more than 100 types of cancers has proven far more complex than imagined at that time. Oncologists resort to a gallows-humor explanation: One tumor, says Otis Brawley of the ACS, is smarter than 100 brilliant cancer scientists. ----From Newsweek Sep. 15, 2008 Useful internet MGH Cancer Center: /Links.htm National Cancer Institute Information: /cancerinformation microRNAs (miRNAs) The catalogue of genes involved in cancer also includes genes that are transcribed into noncoding RNAs from which regulatory microRNAs (miRNAs) are generated. There are at least 250 miRNAs in the human genome that carry out RNA-mediated inhibition of the expression of their target protein-coding genes, either by inducing the degradation of their targets’ mRNAs or by blocking their translation. Approximately 10% of miRNAs have been found to be either greatly overexpressed or down-regulated in various tumors, sometimes strikingly so, and are referred to as oncomirs. One example is the 100-fold overexpression of the miRNA miR-21 in glioblastoma multiforme. The original clone of neoplastic cells serves as a reservoir of genetically unstable cells, referred to as cancer stem cells The major features of cellular r