Field_effect_of_healthy_and_diseased_livers_WGS

Recent work in the Campbell group has revealed somatic mutations present in normal, non-cancerous human skin. A subset of the mutations conferred selective advantages to the host cells, leading to clonal expansions and raising the risk for future cancer development. Capturing such somatic mutations in normal tissue is important to advance our understanding about carcinogenesis and could provide prospective medical insights. In this project, our goal is to detect somatic mutations in normal (pre-cancerous) liver tissue. Using Laser Microdissection technology, we will dissect individual liver lobules from patient samples and submit these to sequencing. For each patient sample, we aim to sequence multiple lobules to characterise the mutagenic burden. Samples will be taken from patients with different liver disease aetiologies, including alcoholism and obesity, with a view on distinguishing the prevalent mutation types occurring in each disease context. We will perform both whole genome and targeted sequencing, initially using the WTSI cancer panel. Later we aim to use a novel bait set that captures both cancer genes as well as genes relevant to the non-cancerous samples (ie. genes implicated in hereditary disorders, immune sequences).

Type: Other
Archiver: European Genome-Phenome Archive (EGA)

2 Datasets 2 Publications

Click on a Dataset ID in the table below to learn more, and to find out who to contact about access to these data

Dataset ID	Description	Technology	Samples
EGAD00001004578	Chronic liver injury predisposes to cirrhosis and hepatocellular carcinoma, but how somatic mutations accumulate in liver disease is unexplored. We sequenced whole genomes of 400 microdissections of 100-500 hepatocytes from 5 normal and 6 cirrhotic livers. Compared to normal liver, cirrhotic liver had higher mutation burden, especially structural variants, including chromothripsis. Cirrhotic nodules were oligoclonal; sometimes entirely derived from a single, recent common ancestor. Clonal expansions millimeters in diameter occurred in cirrhosis in the absence of known driver mutations. Endogenous mutational processes predominated, although signatures of polycyclic aromatic hydrocarbon and aristolochic acid exposure occurred in some samples. Up to 10-fold within-patient variation in activity of exogenous signatures existed between adjacent cirrhotic nodules, with both clone-specific and microenvironmental forces shaping this heterogeneity. Synchronous hepatocellular carcinomas drew from the same repertoire of mutational signatures as background cirrhotic liver, but with higher burden. Somatic mutations chronicle the exposures, toxicity, regeneration and clonal structure of liver tissue as it progresses from health to disease.	HiSeq X Ten	577
EGAD00001006255	Chronic liver disease is associated with metabolic dysregulation, liver failure and hepatocellular carcinoma. We analysed somatic mutations from 1202 genomes across 32 liver samples, including normal controls, alcohol-related and non-alcoholic fatty liver disease. Five of 27 patients with liver disease carried hotspot driver mutations in FOXO1, the major transcription factor downstream of insulin signalling. FOXO1 mutations were independently acquired by up to 5 distinct clones within the same patient’s sample, and impaired insulin-mediated nuclear export of FOXO1. GPAM, which produces storage triacylglycerol from dietary calories, also had significant excess of mutations, similarly exhibiting convergent evolution within biopsies. Telomeres were shorter in diseased than normal liver, with attrition more pronounced in larger clones. Multiple independent acquisitions of drivers within one small liver sample imply that such mutations could affect hundreds of grams of tissue across the whole organ, potentially contributing to systemic metabolic dysfunction.	HiSeq X Ten Illumina NovaSeq 6000	1111

Publications	Citations
Somatic mutations and clonal dynamics in healthy and cirrhotic human liver. Brunner SF, Roberts ND, Wylie LA, Moore L, Aitken SJ, Davies SE, Sanders MA, Ellis P, Alder C, Hooks Y, Abascal F, Stratton MR, Martincorena I, Hoare M, Campbell PJ. Nature 574: 2019 538-542	153
Acetyl-CoA metabolism drives epigenome change and contributes to carcinogenesis risk in fatty liver disease. Assante G, Chandrasekaran S, Ng S, Tourna A, Chung CH, Isse KA, Banks JL, Soffientini U, Filippi C, Dhawan A, Liu M, Rozen SG, Hoare M, Campbell P, Ballard JWO, Turner N, Morris MJ, Chokshi S, Youngson NA. Genome Med 14: 2022 67	5