Project description:We provide the first in vivo evidence of global and local chromatin changes in human aging by analyzing cfDNA from the blood of individuals of different age groups. Our results show that nucleosome signals inferred from cfDNA are consistent with the redistribution of heterochromatin observed in cellular senescence and aging in other model systems. It also revealed age and deteriorating health status correlate with a low-level enrichment of signals from cells in the thyroid gland. In addition, we detected an overall nucleosome loss at several genomic locations, such as transcription start and termination sites, 5’UTR of L1HS retrotransposons and dimeric AluY elements with age.
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:We report a gene expression data on human serum samples for 312 individuals. By examing individuals of different ages. We can have a better understanding of gene expressions associated with aging.
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:The genome-wide analysis of cfDNA fragmentation patterns in DENQCMs and maternal plasma was performed by deep sequencing using Illumina Novaseq to confirm their biological characteristics. We first performed deep whole genome sequencing of the cfDNA extracted from DENQCMs and maternal plasma cfDNA. Then we analyzed the sequencing data and compared various characteristics of cfDNA fragmentation patterns, such as dinucleotide composition, nucleosome protection length, and nucleosome occupancy based on a windowed protection score (WPS), to the submitter-provided processed data from a healthy individual IH01 (GEO accession GSM1833276).
Project description:We report the results of MIRA-Seq-based high-throughput profiling of the bovine fibroblast methylome from three different individuals at two different ages (5 and 16 months of age) to determine the stability of methylation with age. Examination of methylation in one cell line (fibroblasts) of three individuals at two ages (5 and 16 months).
Project description:We report the results of MIRA-Seq-based high-throughput profiling of the bovine fibroblast methylome from three different individuals at two different ages (5 and 16 months of age) to determine the stability of methylation with age.
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.
Project description:Circulating nucleic acids are present in plasma and are derived from a range of cell types, mainly cells of hematopoietic origin, enabling their use as biomarkers for diseases involving these cell types. Using cell type-specific methylation markers, we determined that megakaryocytes are major contributors to cfDNA (~26%), while erythroblasts contribute 1-4% of cfDNA in healthy individuals. Additionally, we identified megakaryocyte-derived DNA within platelets, providing non-invasive access to the megakaryocyte genome and epigenome. Analysis of cfDNA in women who have received male platelet transfusions indicates that megakaryocyte-derived cfDNA does not originate from platelets but is rather released directly from megakaryocytes. The concentration of megakaryocyte-derived cfDNA is elevated in individuals with pathologies involving increased platelet production (Essential Thrombocythemia, Idiopathic Thrombocytopenic Purpura) and decreased by bone marrow suppression (due to chemotherapy), while erythrocyte progenitor cfDNA is elevated in patients with Thalassemia. Megakaryocyte- and erythroblast-specific DNA methylation patterns may serve as novel biomarkers for pathologies involving increased or decreased thrombopoiesis and erythropoiesis.