大規模拓撲變化抑制結直腸癌惡性進展
作者:
小柯機器人發布時間:2020/8/26 13:36:38
近日,美國哈佛大學Bradley E. Bernstein、Martin J. Aryee等研究人員合作發現,大規模拓撲變化抑制結直腸癌惡性進展。這一研究成果於2020年8月24日在線發表在國際學術期刊《細胞》上。
研究人員將結腸腫瘤和正常結腸的拓撲圖與表觀遺傳、轉錄和成像數據進行了整合,以表徵染色質環、拓撲相關域和大規模區室的變化。研究人員發現,在腫瘤中,開放和封閉基因組區室的空間分配受到了嚴重損害。這種重組伴隨著區室特異性的低甲基化和染色質變化。此外,研究人員在經典的A和B區室之間的界面處鑑定出一個在腫瘤中重新組織的區室。
值得注意的是,在積累了過量分裂的非惡性細胞中也出現了類似的變化。這些分析表明,拓撲變化在誘導抗腫瘤免疫基因的同時抑制了幹細胞和侵襲程序,因此可能抑制惡性進展。這些發現質疑了傳統觀點,即腫瘤相關的表觀基因組改變主要是致癌的。
據悉,DNA甲基化和染色質的廣泛變化在癌症中有充分報導,但是高階染色體結構的命運仍然不清楚。
附:英文原文
Title: Large-Scale Topological Changes Restrain Malignant Progression in Colorectal Cancer
Author: Sarah E. Johnstone, Alejandro Reyes, Yifeng Qi, Carmen Adriaens, Esmat Hegazi, Karin Pelka, Jonathan H. Chen, Luli S. Zou, Yotam Drier, Vivian Hecht, Noam Shoresh, Martin K. Selig, Caleb A. Lareau, Sowmya Iyer, Son C. Nguyen, Eric F. Joyce, Nir Hacohen, Rafael A. Irizarry, Bin Zhang, Martin J. Aryee, Bradley E. Bernstein
Issue&Volume: 2020-08-24
Abstract: Widespread changes to DNA methylation and chromatin are well documented in cancer,but the fate of higher-order chromosomal structure remains obscure. Here we integratedtopological maps for colon tumors and normal colons with epigenetic, transcriptional,and imaging data to characterize alterations to chromatin loops, topologically associateddomains, and large-scale compartments. We found that spatial partitioning of the openand closed genome compartments is profoundly compromised in tumors. This reorganizationis accompanied by compartment-specific hypomethylation and chromatin changes. Additionally,we identify a compartment at the interface between the canonical A and B compartmentsthat is reorganized in tumors. Remarkably, similar shifts were evident in non-malignantcells that have accumulated excess divisions. Our analyses suggest that these topologicalchanges repress stemness and invasion programs while inducing anti-tumor immunitygenes and may therefore restrain malignant progression. Our findings call into questionthe conventional view that tumor-associated epigenomic alterations are primarily oncogenic.
DOI: 10.1016/j.cell.2020.07.030
Source: https://www.cell.com/cell/fulltext/S0092-8674(20)30938-7
Cell:《細胞》,創刊於1974年。隸屬於細胞出版社,最新IF:36.216