1. Evidence of DNA methylation heterogeneity and epipolymorphism in kidney cancer tissue samples.
- Author
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Rossi SH, Dombrowe V, Godfrey L, Bucaciuc Mracica T, Pita S, Milne-Clark T, Kyeremeh J, Park G, Smith CG, Lach RP, Babbage A, Warren AY, Mitchell TJ, Stewart GD, Schwarz R, and Massie CE
- Abstract
Clear cell renal cell carcinoma (ccRCC) is characterised by significant genetic heterogeneity, which has diagnostic and prognostic implications. Very limited evidence is available regarding DNA methylation heterogeneity. We therefore generate sequence level DNA methylation data on 136 multi-region tumour and normal kidney tissue from 18 ccRCC patients, along with matched whole exome sequencing (85 samples) and gene expression (47 samples) data on a subset of samples. We perform a comprehensive systematic analysis of heterogeneity between patients, within a patient and within a sample. We demonstrate that bulk methylation data may be deconvoluted into cell-type-specific latent methylation components (LMCs), and that LMC1, which is likely to represent T cells, is associated with prognostic parameters. Differential epipolymorphism was noted between ccRCC and normal tissue in the promoter region of genes which are known to be associated with kidney cancer. This was externally validated in an independent cohort of 71 ccRCC and normal kidney tissues. Differential epipolymorphism in the gene promoter was a predictor of gene expression, after adjusting for average methylation. This represents the first evaluation of epipolymorphism in ccRCC and suggests that gains and losses in methylation disorder may have a functional relevance, gleaning important information on tumourigenesis., Competing Interests: Competing interests: GDS has received educational grants from Pfizer, AstraZeneca, and Intuitive. Surgical; consultancy fees from Pfizer, Merck, MSD, EUSA Pharma, and CMR Surgical; travel expenses from Pfizer; and speaker fees from MSD and Pfizer. GDS is Clinical lead (urology) National Kidney Cancer Audit and Topic Advisor for the NICE kidney cancer guideline. AWY is a member of the Clinical Reference Group for the National Kidney Cancer Audit. All other authors declare no competing interests. Ethics approval and consent to participate: Ethics approval was obtained (DIAMOND; Ethics REC ID 03/018, East of England—Cambridge Central Research Ethics Committee). Written informed consent was obtained from all participants involved in the study. All methods were performed in accordance with the relevant guidelines/regulations and are compliant with good scientific practice., (© 2025. The Author(s).)
- Published
- 2025
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