Project description:Heterogeneity in DNA methylation status may exist between primary tumors and cfDNA. We compared the genome-wide DNA methylation status between FNA sample of pancreatic tumor and cfDNA samples from the same patients. MBD-sequencing (seq) was performed in paired samples of FNA and cfDNA from two patients. The majority of DNA methylation peaks overlapped in FNA and cfDNA samples (82.6% and 82.9% in patients #1 and #73, respectively). DNA methylation levels of each gene in FNA and cfDNA samples were highly correlated with each other (r=0.98 and 0.97 in samples 1 and 73, respectively)
Project description:We explored the differential methylation patterns found in cfDNA between no neoplasia (NN; individuals with no colorectal findings, benign pathologies and non-advanced adenomas) and patients with advanced neoplasia (AN; advanced adenomas and colorectal cancer) using pooled samples, for the discovery of non-invasive methylation biomarkers for CRC screening. cfDNA was extracted from serum samples and methylation measurements were assessed with the Infinium MethylationEPIC BeadChip. Data was mainly preprocessed and analyzed with R/Bioconductor packages.
Project description:We performed all stimulatory experiments using THP1 cell line as a representative of primary human monocytes to show fundamental role of the cfDNA in healthy organisms. The experiments were conducted in duplicates using plasma containing cfDNA (NP) and the reference one with cfDNA removed by DNase (TP) to recognize unequivocally the effect of plasma cfDNA on transcriptome and proteome of monocytes. We used native human plasma samples obtained from healthy volunteers with no animal serum addition to cultivation medium in order to avoid the presence of uncharacterized animal cfDNA in the experiments.
Project description:Acute rejection threatens kidney allograft longevity. Cell-free DNA (cfDNA) is a real-time marker of organ injury and immune response. DNA methylation is an epigenetic marker that regulates gene expression. We aim to elucidate differential methylation of total plasma cfDNA between pediatric kidney transplant recipients in the presence compared to the absence of acute rejection. In doing so, we hope to exploit the property of cfDNA as a real-time biomarker and build on available testing to identify genes and processes participating in acute allograft rejection pathophysiology in kidney transplantation. Twenty plasma cfDNA samples from pediatric kidney transplant recipients were collected at the time of allograft biopsy. Using whole genome bisulfite sequencing (WGBS), differentially methylated cytosines were identified in presence vs absence of acute rejection. Separate analyses were performed comparing those with borderline rejection to those with rejection, and to those without rejection. Differentially methylated cytosines were then assessed for gene associations and pathway enrichments. Acute rejection was present in 7 biopsies, borderline rejection in 4 biopsies, and no rejection in 9 biopsies. In the comparison of acute rejection to non-rejection biopsies, there were 34,356 differentially methylated cytosines corresponding to 1,269 associated genes, and 533 enriched pathways. These numbers were all substantially greater (4x-13x) than the comparisons made between acute rejection against those with borderline rejection, and between non-rejection against borderline rejection. Prominently enriched pathways between samples of individuals with and without acute rejection were related to immune cell regulation, inflammatory response, lipid metabolism, and tryptophan-kynurenine metabolism. Our data suggest methylation plays a role in development of or response to acute kidney allograft rejection. Specifically, differentially methylated pathways associated with acute rejection include those related to immune and inflammatory responses.
Project description:Genome wide DNA methylation profiling of A2780 cells untreated (mock), treated with H2O2 for 30 min (H2O2 30 min), or treated with H2O2 for 30 min with additional 2.5 hour resting ( H2O2 3h) . The Illumina’s Infinium Human Methylation450 Beadchip Kit (WG-314-1001) was used to obtain DNA methylation profiles across approximately 450,000 CpGs.
Project description:Genome wide DNA methylation profiling of A2780 cells 1) infected with control virus, no H2O2 (Scr_mock), 2) infected with control virus with H2O2 treatment (30 min plus 2.5 h resting) (Scr_H2O2), 3) infected with shTET2 virus, no H2O2 (shTET2_mock), and 4) infected with shTET2 virus, with H2O2 treatment (30 min plus 2.5 h resting) (shTET2_H2O2, two biological replicates). The Illumina’s Infinium Human Methylation450 Beadchip Kit (WG-314-1001) was used to obtain DNA methylation profiles across approximately 450,000 CpGs.
Project description:This study aimed to evaluate the cost-effective and genome-wide cell-free reduced representation bisulfite sequencing (cfRRBS) method combined with computational deconvolution for effective disease monitoring in patients with esophageal adenocarcinoma (EAC). cfDNA methylation profiling with cfRRBS was performed on 162 blood plasma samples from 33 EAC cancer patients and 28 blood plasma samples from 20 healthy donors. In addition, for reproducibility testing purposes of the method, 9 plasma samples were re-prepped (library was re-made) and re-sequenced once (n=9) or twice (n=1). As a reference for the data deconvolution cfRRBS was performed on 7 EAC tumor tissue (FFPE) samples.
Project description:We aimed to clarify the cell-free DNA (cfDNA) physiological role. We exposed THP1 cells to plasma from healthy individuals with and without cfDNA and compared their transcriptomes and proteomes.
Project description:Disease progression and therapeutic resistance are hallmarks of advanced stage prostate cancer (PCa), which remains a major cause of cancer-related mortality around the world. Longitudinal studies, coupled with the use of liquid biopsies, offer a potentially new and minimally invasive platform to study the dynamics of tumour progression. Our study aimed to investigate the dynamics of personal methylomic profiles of metastatic PCa (mPCa) patients, during disease progression and therapy administration. 52 plasma samples from 9 patients with mPCa were collected, longitudinally, over 13-21 months. After cell-free DNA (cfDNA) isolation, DNA methylation was profiled using the Infinium MethylationEPIC BeadChip and analysed using the minfi software. The top 5% most variable probes across time, within each individual, were utilised to study dynamic methylation patterns during disease progression and therapeutic response. Statistical testing was carried out to identify and validate ctDNA differentially methylated genes (DMGs). Personal cfDNA global methylation patterns were temporally stable throughout disease course. A proportion of analysed CpG sites presented a dynamic temporal pattern that was consistent with clinical events, such as therapy administration, and were prominently associated with immune response pathways. Study of ctDNA identified >2,000 DMGs with dynamic methylation patterns. We concluded that longitudinal assessment of cfDNA methylation in mPCa patients unveiled dynamic patterns associated with the occurrence of specific clinical events, thus highlighting the potential of using liquid biopsies to study PCa progression.