Epigenetics ofPNLIPRP1in human pancreas reveals a molecular path between type 2 diabetes and pancreatic cancer

Abstract

AbstractBackgroundType 2 diabetes (T2D) increases the risk of pancreatic ductal adenocarcinoma (PDAC), which could be due to an epigenetic mechanism.MethodsWe explored the association between T2D and whole pancreas methylation in 141 individuals, of which 28 had T2D, using Illumina MethylationEPIC 850K BeadChip arrays. We performed downstream functional assessment in the rat acinar pancreas cell line AR42J. To further understand the role of our candidate gene in humans, we tested whether null variants were associated with T2D and related traits using the UK biobank.ResultsMethylation analysis identified one significant CpG associated with T2D: hypermethylation in an enhancer inPNLIPRP1, an acinar-specific gene.PNLIPRP1expression was decreased in T2D individuals. Using a rat acinar cell line, we 1/ confirmed decreasedPnliprp1in response to a diabetogenic treatment, and 2/ inPnliprp1knockdown, an up-regulation of cholesterol biosynthesis, cell cycle down-regulation, decreased expression of acinar markers and increased expression of ductal markers pointing towards acinar-to-ductal metaplasia (ADM), a hallmark of PDAC initiation. Using exome data from UK Biobank, we show that rarePNLIPRP1null variants associated with increased glucose, BMI and LDL-cholesterol.Conclusions/interpretationWe present evidence that an epigenetically-regulated gene associates with T2D risk, and might promote ADM and PDAC progression, opening new insights into early prevention of PDAC.