PO.MCB07.02 · 分子与细胞生物学
解码三维增强子结构确定前列腺癌中的分级致癌调控程序
Decoding 3D enhancer architecture identifies hierarchical oncogenic regulatory programs in prostate cancer
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
非编码DNA区域(尤其是位于调控元件中的区域)的异常越来越被认为是前列腺癌的一个标志。然而,绘制支撑肿瘤特异性转录的增强子仍具有挑战性。在此,我们开发了一个整合工作流程,通过分析来自前列腺肿瘤和正常组织以及前列腺细胞系的204个H3K27ac ChIP-seq数据集,对前列腺癌特异性增强子(PSE)进行优先排序。我们通过从Hi-C数据集中识别关键的致癌拓扑关联结构域(TAD),将差异激活的增强子图景与前列腺癌中的三维(3D)染色质组织联系起来。我们选择了chr6q24.1处一个此前未表征但高优先级的基因座进行深入研究。为界定chr6q24.1处的癌症特异性3D结构,我们在RWPE-1(正常)和22Rv1(癌症)细胞中生成了核小体分辨率的区域捕获Micro-C(RCMC)图谱。这揭示了高度嵌套的增强子-启动子(E-P)相互作用,我们称之为多连接增强子中枢,这些相互作用在癌症中显著存在但在正常中缺失,超过了传统Hi-C对以增强子为中心接触的灵敏度。对该基因座各个增强子进行CRISPR/Cas9缺失,随后进行多组学分析,揭示了两类不同的增强子。中央PSE(cPSE)作为核心调控组织者发挥功能,其缺失削弱了其他PSE的活性、瓦解了整个基因座范围的染色质相互作用、降低了靶基因表达并损害了癌细胞增殖,而不广泛改变CTCF/黏连蛋白结构。相比之下,冗余PSE(rPSE)由邻近的救援增强子缓冲,通过加强替代E-P接触的代偿性重新布线来保持转录。我们的数据还提示,这两类增强子行为与FOXA1(前列腺癌中的先锋转录因子)的差异活性相关。总之,我们的研究揭示了对前列腺肿瘤发生至关重要的癌症特异性多连接增强子中枢,并揭示了增强子的调控层级,提供了一个框架来功能性表征和验证维持前列腺癌表型的致癌非编码DNA区域。这项研究推进了我们对非编码调控区域的理解,并为开发基于表观基因组的新型精准前列腺癌临床干预提供了未来机会。
查看英文原文 English abstract
Aberrations in non‑coding DNA regions, particularly those located in regulatory elements, are increasingly implicated as a hallmark of prostate cancer. Yet, mapping enhancers that underpin tumor‑specific transcription remains challenging. Here, we developed an integrative workflow to prioritize prostate cancer‑specific enhancers (PSEs) by analyzing 204 H3K27ac ChIP-seq datasets from prostate tumor and normal tissues, alongside prostate cell lines. We connected the differentially activated enhancer landscape to three‑dimensional (3D) chromatin organization in prostate cancer by identifying key oncogenic topologically associating domains (TADs) from Hi-C datasets. We selected a previously uncharacterized but high-priority locus at chr6q24.1 for in-depth study. To define cancer-specific 3D architecture at chr6q24.1, we generated Region‑Capture Micro‑C (RCMC) maps at nucleosome resolution in RWPE‑1 (normal) and 22Rv1 (cancer) cells. This revealed highly nested enhancer-promoter (E-P) interactions, which we termed multi-connected enhancer hubs, that were prominent in cancer but absent in normal, exceeding the sensitivity of conventional Hi-C for enhancer-centered contacts. CRISPR/Cas9 deletion of individual enhancers across the locus, followed by multi‑omic profiling, revealed two distinct enhancer classes. Central PSEs (cPSEs) function as core regulatory organizers, whose deletions weakened activities of other PSEs, collapsed locus-wide chromatin interactions, reduced target gene expression, and impaired cancer cell proliferation without broadly altering CTCF/cohesin architecture. In contrast, redundant PSEs (rPSEs) are buffered by neighboring rescuing enhancers to preserve transcription via compensatory rewiring that strengthens alternative E-P contacts. Our data also suggest that these two classes of enhancer behaviors are associated with differential activity of FOXA1, a pioneer transcription factor in prostate cancer. Together, our study revealed cancer-specific, multi-connected enhancer hubs essential for prostate tumorigenesis and uncovered the regulatory hierarchy of enhancers, providing a framework to functionally characterize and validate oncogenic non-coding DNA regions that sustain prostate cancer phenotypes. This study advances our understanding of non-coding regulatory regions and offers future opportunities for developing novel precision epigenome-based clinical interventions for prostate cancer.
利益披露 Disclosure
H. Cao, None..
Z. Wu, None..
B. Ji, None..
S. Yang, None..
L. Gonzalez-Smith, None..
A. Vu, None..
S. K. Rhie, None.