tailieunhanh - Báo cáo y học: " Large-scale analysis of chromosomal aberrations in cancer karyotypes reveals two distinct paths to aneuploidy"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: Large-scale analysis of chromosomal aberrations in cancer karyotypes reveals two distinct paths to aneuploidy. | Ozery-Flato et al. Genome Biology 2011 12 R61 http 2011 12 6 R61 Genome Biology RESEARCH Open Access Large-scale analysis of chromosomal aberrations in cancer karyotypes reveals two distinct paths to aneuploidy 1 1 Michal Ozery-Flato 1 Chaim Linhart Luba Trakhtenbrot Shai Izraeli and Ron Shamir Abstract Background Chromosomal aneuploidy that is to say the gain or loss of chromosomes is the most common abnormality in cancer. While certain aberrations most commonly translocations are known to be strongly associated with specific cancers and contribute to their formation most aberrations appear to be non-specific and arbitrary and do not have a clear effect. The understanding of chromosomal aneuploidy and its role in tumorigenesis is a fundamental open problem in cancer biology. Results We report on a systematic study of the characteristics of chromosomal aberrations in cancers using over 15 000 karyotypes and 62 cancer classes in the Mitelman Database. Remarkably we discovered a very high cooccurrence rate of chromosome gains with other chromosome gains and of losses with losses. Gains and losses rarely show significant co-occurrence. This finding was consistent across cancer classes and was confirmed on an independent comparative genomic hybridization dataset of cancer samples. The results of our analysis are available for further investigation via an accompanying website. Conclusions The broad generality and the intricate characteristics of the dichotomy of aneuploidy ranging across numerous tumor classes are revealed here rigorously for the first time using statistical analyses of large-scale datasets. Our finding suggests that aneuploid cancer cells may use extra chromosome gain or loss events to restore a balance in their altered protein ratios needed for maintaining their cellular fitness. Background Most cancer genomes undergo large scale alterations that dramatically alter their content and structure 1 . This phenomenon of .