Abstract 6218: Haplotype-resolved analysis of cancer genomes and epigenomes using Oxford Nanopore sequencing

Abstract

Abstract Cancer is a complex and dynamic disease driven by somatic genomic and epigenomic alterations that accumulate over time. These changes give rise to heterogeneous collections of cells or clones, each with distinct (epi)genomic profiles within a single tumour. Accurate characterisation of these changes is crucial for understanding the mechanisms driving the disease, identifying potential therapeutic targets, and personalising treatment strategies. Due to the technological constraints of short-read and array-based approaches, cancer research has historically had a strong focus on detecting small genomic changes like SNPs and small indels (SNVs) as well as the broad characterisation of large-scale copy number changes (CNVs), mostly ignoring other important variant classes and epigenetic modifications. Here we demonstrate how Oxford Nanopore native long-read sequencing enables the direct detection of not only SNVs, but also break point-resolved simple and complex structural variants (SVs and CNVs), haplotype phasing of all variant types, and identification of DNA modifications like 5-methylcytosine (5mC) and 5-hydroxy-methylcytosine (5hmC) from a single tumour-normal dataset. We illustrate how our end-to-end somatic workflow streamlines analysis for the different variant classes and benchmark somatic SNV and SV calling performance using well characterised cancer cell lines and in-silico benchmarking datasets at different sequencing depths. Finally, we use real-world tumour-normal pairs to showcase a comprehensive sample to answer tumour-normal analysis using Nanopore sequencing. This includes the characterisation of complex patterns of somatic SVs in the different cancer samples, the identification of unique 5mC methylation patterns, exploring characteristic differences in 5hmC levels between tumour and normal samples as well as showing how Nanopore long reads enable haplotype and clone specific CNV calling as well as phasing of genetic and epigenetic variation. Citation Format: Philipp Rescheneder, Phill James, Sean McKenzie, Andrea Talenti, Sergey Aganezov, Dan Turner, Sissel Juul. Haplotype-resolved analysis of cancer genomes and epigenomes using Oxford Nanopore sequencing [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 6218.