癌細胞克隆轉錄和表觀遺傳狀態維持的機制
作者:
小柯機器人發布時間:2020/6/30 19:48:56
以色列魏茨曼科學研究所Amos Tanay課題組通過單細胞分析,揭示了癌細胞克隆如何維持其轉錄和表觀遺傳狀態。2020年6月29日,《自然-遺傳學》發表了這一成果。
研究人員通過單細胞轉錄和DNA甲基化分析與Luria-Delbrück實驗設計相結合的方法,證明多種類型的癌細胞中存在克隆穩定的表觀遺傳記憶。結腸癌克隆細胞群的縱向轉錄和遺傳分析表明上皮到間充質轉錄特徵的緩慢漂移譜,這似乎與遺傳變異無關。DNA甲基化圖譜與這些特徵相關,但也反映了獨特的節律樣甲基化丟失過程。在大多數情況下,甲基化變化可以通過整體反式作用因子的作用來解釋。
但是,對於特定類型的啟動子,特別是癌症-睪丸抗原,去阻抑與順式甲基化的喪失有關,並可能由其驅動。這項研究表明,通過表觀遺傳記憶可以使癌細胞中的基因亞克隆結構多樣化。
研究人員表示,克隆調控程序的傳播利於癌症發展。人們對表觀遺傳機制如何與遺傳誘導因子相互作用以重塑這一過程了解甚少。
附:英文原文
Title: Single-cell analysis of clonal maintenance of transcriptional and epigenetic states in cancer cells
Author: Zohar Meir, Zohar Mukamel, Elad Chomsky, Aviezer Lifshitz, Amos Tanay
Issue&Volume: 2020-06-29
Abstract: Propagation of clonal regulatory programs contributes to cancer development. It is poorly understood how epigenetic mechanisms interact with genetic drivers to shape this process. Here, we combine single-cell analysis of transcription and DNA methylation with a Luria–Delbrück experimental design to demonstrate the existence of clonally stable epigenetic memory in multiple types of cancer cells. Longitudinal transcriptional and genetic analysis of clonal colon cancer cell populations reveals a slowly drifting spectrum of epithelial-to-mesenchymal transcriptional identities that is seemingly independent of genetic variation. DNA methylation landscapes correlate with these identities but also reflect an independent clock-like methylation loss process. Methylation variation can be explained as an effect of global trans-acting factors in most cases. However, for a specific class of promoters—in particular, cancer–testis antigens—de-repression is correlated with and probably driven by loss of methylation in cis. This study indicates how genetic sub-clonal structure in cancer cells can be diversified by epigenetic memory.
DOI: 10.1038/s41588-020-0645-y
Source: https://www.nature.com/articles/s41588-020-0645-y