EZH2 gain-of-function mutations distort H3K27me3 landscapes and transform transcriptional responses to PRC2 inhibition [RNA-seq]. EZH2 gain-of-function mutations distort H3K27me3 landscapes and transform transcriptional responses to PRC2 inhibition [RNA-seq]

We have modelled several tumor-associated PRC2 mutations in a single isogenic system in order to reveal their comparative impacts on chromatin and transcription. We have also explored the link between EZH2 mutational status and abnormal H3K27 methylation in a unique longitudinal cohort of follicular lymphoma (FL) patient samples. Overall design: Differential analysis comparing gene expression profiles of WT vs PRC2 mutant immortalized mouse embryonic fibroblasts (iMEFs). The panel of PRC2 mutations encompasses: Ezh2-KO, Eed-KO, H3.3K27M, and the gain-of-function Y641F Ezh2 mutant (Ezh2Y641F). RNA-Seq was also used to profile gene expression changes in WT and Ezh2Y641F iMEFs treated with two doses of the EZH2 inhibitor UNC1999. Gene expression differential analysis between WT and EZH2 mutant FL samples, as measured by RNA-Seq.

我们在单一同基因系统中构建了多种肿瘤相关多梳抑制复合体2（Polycomb Repressive Complex 2, PRC2）突变模型，以揭示其对染色质与转录的相对调控效应。我们还在一组独特的滤泡性淋巴瘤（Follicular Lymphoma, FL）患者样本纵向队列中，探究了EZH2（Enhancer of Zeste Homolog 2）突变状态与异常组蛋白H3K27甲基化之间的潜在关联。

总体实验设计：对比野生型（Wild Type, WT）与PRC2突变型永生化小鼠胚胎成纤维细胞（immortalized mouse embryonic fibroblasts, iMEFs）的基因表达谱，开展差异分析。本次纳入分析的PRC2突变组合包括：Ezh2基因敲除（Ezh2-KO）、Eed基因敲除（Eed-KO）、组蛋白H3.3K27M突变，以及功能获得性Ezh2 Y641F突变体（Ezh2Y641F）。本研究采用RNA测序（RNA-Seq）对经两种剂量EZH2抑制剂UNC1999处理的野生型与Ezh2Y641F iMEFs的基因表达变化进行谱分析。此外，通过RNA测序对野生型与EZH2突变型FL样本开展基因表达差异分析。