Abstract 7355: Integration analysis of lncRNAs and R-loops in 3D genome organization and gene regulation in the cancer genome

Abstract Existing evidence shows that some long non-coding RNAs (lncRNAs) can recruit chromatin regulators and form R-loops to mediate CCTCC-binding factor (CTCF) binding at topologically associated domain (TAD) boundaries to activate transcription of target genes. However, it remains unclear to what extent such lncRNA-dependent chromatin organization events occur genome-wide in normal and cancer cells. By curated public data of lncRNA, CTCF, RAD21 profiles and integrative analysis of multi-omics data using innovative computational approaches, we investigated global associations of lncRNAs and R-loops with activities of transcription factors and chromatin regulators in gene expression regulations across multiple human cell types. We developed a comprehensive computational pipeline for cross-cell-type analysis of lncRNA and protein-coding gene expression profiles and transcription factor binding profiles. We identified a total of 542 candidate genomic regions where lncRNAs play a pivotal role in regulating target genes by facilitating CTCF/cohesin binding. R-loops are enriched at CTCF/cohesin binding sites, suggesting their potential contribution to CTCF binding. Additionally, our findings underscore the significant cell-type specificity of CTCF binding patterns across the genome. This work adds knowledge to cancer genome organization and gene regulation, and builds foundations for further functional and mechanistic studies of lncRNAs and R-loops in the human genome. Citation Format: Shengyuan Wang, Zhenjia Wang, Yuh-Hwa Wang, Hui Li, Peter Todd Stukenburg, Chongzhi Zang. Integration analysis of lncRNAs and R-loops in 3D genome organization and gene regulation in the cancer genome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7355.