Project description:Transcriptional deregulation of oncogenic pathways is a hallmark of cancer, and can be due to epigenetic alterations. 5-hydroxymethylcytosine is a recently discovered epigenetic modification that has not been studied in pancreatic cancer. Genome-wide analysis of 5-hmC enriched loci was conducted in low-passage pancreatic cancer cell lines and primary patient-derived xenografts and revealed strikingly altered patterns in neoplastic tissues. Differentially hydroxymethylated regions preferentially affected regulatory regions of the genome, specifically overlapping with H3K4me1 enhancers. Gain of 5-hmC was correlated with upregulation of the cognate transcripts, including many oncogenic pathways implicated in pancreatic neoplasia. Specifically, BRD4 was overexpressed and acquired 5hmC at enhancer regions in majority of neoplastic samples. Functionally, acquisition of 5hmC at BRD4 promoter regulated increase in transcript expression. Furthermore, blockade of BRD4 inhibited pancreatic cancer growth in vivo. In summary, redistribution of 5-hmC and preferential enrichment at oncogenic enhancers is a novel regulatory mechanism in human cancer. Genome-wide analysis of 5-hmC enriched loci was conducted in low-passage pancreatic cancer cell lines and primary patient-derived xenografts
Project description:Pancreatic adenocarcinoma (PDAC) is a lethal disease and it is the most common type of pancreatic cancer. Majority of the pancreatic cancers harbor alterations in the Kras gene. Currently there are no approved drugs that target Kras directly and it's downstream effect on the epigenome remains unknown. In this study, we investigated the epigenetic landscape of pancreatic cancer cells which harbor the inducible KrasG12D allele. We performed RNA-seq, ChIP-seq against 6 different histone marks, ATAC-seq and RRBS to assess the changes in the epigenome after oncogenic KrasG12D induction.
Project description:We aimed to decipher human APOBEC3A driven genomic differences in pancreatic tumors in vivo using a genetically engineered mouse model for pancreatic cancer. Murine pancreatic tumor formation was driven by p53fl/+;KrasLSL-G12D/+;Pdx1-Cre;Rosa26LSL-YFP (PKCY) and p53fl/+;KrasLSL-G12D/+;Pdx1-Cre; Rosa26LSL-YFP; A3A+/- (A3A PKCY).
Project description:We aimed to decipher human APOBEC3A driven mutational differences in pancreatic tumor in vivo using a genetically engineered mouse model of pancreatic cancer. Murine pancreatic tumor formation was driven by p53fl/+;KrasLSL-G12D/+;Pdx1-Cre;Rosa26LSL-YFP (PKCY) and p53fl/+;KrasLSL-G12D/+;Pdx1-Cre; Rosa26LSL-YFP; A3A+/- (A3A PKCY).
Project description:HNF1A and UTX are putative tumor suppressors in pancreatic cancer. In this study, we have combined mouse genetics, transcriptomics and genome binding studies to link HNF1A and UTX in a molecular mechanism that suppresses pancreatic cancer. In this session, we have profiled UTX, HNF1A, H3K27me3 and H3K27ac in normal and UTX- or HNF1A-deficient mouse pancreas by ChIP-seq experiments. We show that HNF1A recruits UTX to its genomic targets in pancreatic acinar cells, which results in remodeling of the chromatin landscape and activation of a broad transcriptional program of differentiated acinar cells, which in turn indirectly suppresses tumor suppressor pathways.
Project description:Pancreatic cancer is the 3rd most prevalent cause of cancer related deaths in United states alone, with over 55000 patients being diagnosed in 2019 alone and nearly as many succumbing to it. Late detection, lack of effective therapy and poor understanding of pancreatic cancer systemically contributes to its poor survival statistics. Obesity and high caloric intake linked co-morbidities like type 2 diabetes (T2D) have been attributed as being risk factors for a number of cancers including pancreatic cancer. Studies on gut microbiome has shown that lifestyle factors as well as diet has a huge effect on the microbial flora of the gut. Further, modulation of gut microbiome has been seen to contribute to effects of intensive insulin therapy in mice on high fat diet. In another study, abnormal gut microbiota was reported to contribute to development of diabetes in Db/Db mice. Recent studies indicate that microbiome and microbial dysbiosis plays a role in not only the onset of disease but also in its outcome. In colorectal cancer, Fusobacterium has been reported to promote therapy resistance. Certain intra-tumoral bacteria have also been shown to elicit chemo-resistance by metabolizing anti-cancerous agents. In pancreatic cancer, studies on altered gut microbiome have been relatively recent. Microbial dysbiosis has been observed to be associated with pancreatic tumor progression. Modulation of microbiome has been shown to affect response to anti-PD1 therapy in this disease as well. However, most of the studies in pancreatic cancer and microbiome have remained focused om immune modulation. In the current study, we observed that in a T2D mouse model, the microbiome changed significantly as the hyperglycemia developed in these animals. Our results further showed that, tumors implanted in the T2D mice responded poorly to Gemcitabine/Paclitaxel (Gem/Pac) standard of care compared to those in the control group. A metabolomic reconstruction of the WGS of the gut microbiota further revealed that an enrichment of bacterial population involved in drug metabolism in the T2D group.