Genome-wide DNA methylation profiling of cell-free DNA in nipple aspirate fluid for breast cancer
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE238014 | GEO | 2023/09/26
REPOSITORIES: GEO
Similar Datasets
Project description:Sampling the live brain is difficult and dangerous, and withdrawing cerebrospinal fluid is uncomfortable and frightening to the subject, so new sources of real-time analysis are constantly sought. Cell-free DNA (cfDNA) derived from glia and neurons offers the potential for wide-ranging neurological disease diagnosis and monitoring. However, new laboratory and bioinformatic strategies are needed. DNA methylation patterns on individual cfDNA fragments can be used to ascribe their cell-of-origin. Here we describe bisulfite sequencing assays and bioinformatic processing methods to identify cfDNA derived from glia and neurons. In proof-of-concept experiments we describe the presence of both glia- and neuron-cfDNA in the blood plasma of human subjects following mild trauma. These detection of glia- and neuron-cfDNA represents a significant step forward in the translation of liquid biopsies for neurological diseases.
2021-02-06 | GSE126663 | GEO
Project description:Circulating cell-free DNA (cfDNA) in the bloodstream originates from dying cells and is a promising non-invasive biomarker for cell death. Here, we propose an algorithm, CelFiE, to accurately estimate relative abundances of cell types and tissues contributing to cfDNA from epigenetic cfDNA sequencing. In contrast to previous work, CelFiE accommodates low coverage data, does not rely on CpG site curation, and estimates contributions from multiple unknown cell types that are not available in external reference data. In simulations, CelFiE accurately estimates known and unknown cell type proportions from low coverage and noisy cfDNA mixtures, including from rare cell types composing less than 1% of the total mixture. In a positive control of cfDNA extracted from pregnant and non-pregnant women, CelFiE correctly estimates a large placenta component specifically in pregnant women (p = 4.5x10^-5). In cfDNA from ALS patients and age-matched controls, we observed increased cfDNA concentrations in ALS patients (p = 5.0x10^-3), and CelFiE identified a corresponding increased skeletal muscle component (p = 2.4x10^-3), consistent with muscle impairment characterizing ALS. Together these results show CelFiE may be a useful tool for biomarker discovery and monitoring of degenerative disease progression.
2021-01-12 | GSE164600 | GEO
Project description:As a non-invasive blood testing, the detection of cell-free DNA (cfDNA) methylation in plasma is raising increasing interest due to its diagnostic and biology applications. Although extensively used in cfDNA methylation analysis, bisulfite sequencing is less cost-effective. Through enriching methylated cfDNA fragments with MeDIP followed by deep sequencing, we aimed to characterize cfDNA methylome in cancer patients. In this study, we investigated the cfDNA methylation patterns in lung cancer patients by MeDIP-seq. MEDIPS package was used for the identification of differentially methylated regions (DMRs) between patients and normal ones. Overall, we identified 330 differentially methylated regions (DMRs) in gene promoter regions, 33 hypermethylation and 297 hypomethylation respectively, by comparing lung cancer patients and healthy individuals as controls. The 33 hypermethylation regions represent 32 genes. Some of the genes had been previously reported to be associated with lung cancers, such as GAS7, AQP10, HLF, CHRNA9 and HOPX. Taken together, our study provided an alternative method of cfDNA methylation analysis in lung cancer patients with potential clinical applications.
2019-03-31 | E-MTAB-7163 | biostudies-arrayexpress
Project description:The early detection of tissue and organ damage associated with autoimmune diseases (AID) has been identified as key to improve long-term survival, but non-invasive biomarkers are lacking. Elevated cell-free DNA (cfDNA) levels have been observed in AID and inflammatory bowel disease (IBD), prompting interest to use cfDNA as a potential non-invasive diagnostic and prognostic biomarker. Despite these known disease-related changes in concentration, it remains impossible to identify AID and IBD patients through cfDNA analysis alone. By using unsupervised clustering on large sets of shallow whole-genome sequencing (sWGS) cfDNA data, we uncover AID- and IBD-specific genome-wide patterns in plasma cfDNA in both the obstetric and general AID and IBD populations. Supervised learning of the genome-wide patterns allows AID prediction with 50% sensitivity at 95% specificity. Importantly, the method can identify pregnant women with AID during routine non-invasive prenatal screening. Since AID pregnancies have an increased risk of severe complications, early recognition or detection of new onset AID can redirect pregnancy management and limit potential adverse events. This method opens up new avenues for screening, diagnosis and monitoring of AID and IBD.
2022-09-14 | E-MTAB-11607 | biostudies-arrayexpress
Project description:The objective of this study was to identify the tissue expression patterns and biological pathways enriched in term amniotic fluid cell-free fetal RNA by comparing functional genomic analyses of term and second-trimester amniotic fluid supernatants. There were 2,871 significantly differentially regulated genes. In term amniotic fluid, tissue expression analysis showed enrichment of salivary gland, tracheal, and renal transcripts as compared with brain and embryonic neural cells in the second trimester. Functional analysis of genes upregulated at term revealed pathways that were highly specific for postnatal adaptation such as immune function, digestion, respiration, carbohydrate metabolism, and adipogenesis. Inflammation and prostaglandin synthesis, two key processes involved in normal labor, were also activated in term amniotic fluid. This was a prospective whole genome microarray study comparing eight amniotic fluid samples collected from eight women at term who underwent prelabor cesarean delivery and eight second-trimester amniotic fluid samples from routine amniocenteses. A functional annotation tool was used to compare tissue expression patterns in term and second-trimester samples. Pathways analysis software identified physiologic systems, molecular and cellular functions, and upstream regulators that were significantly overrepresented in term amniotic fluid.
2013-04-23 | E-GEOD-46286 | biostudies-arrayexpress
Project description:Whole-genome bisulfite sequencing (BS-Seq) measures cytosine methylation changes at single-base resolution and can be used to profile cell-free DNA (cfDNA). In plasma, ultrashort single-stranded cfDNA (uscfDNA, ~50 nt) has been identified together with 167 bp double-stranded mononucleosomal cell-free DNA (mncfDNA). However, the methylation profile of uscfDNA has not been described. Conventional BS-Seq workflows may not be helpful because bisulfite conversion degrades larger DNA into smaller fragments, leading to erroneous categorization as uscfDNA. We describe the “5mCAdpBS-Seq” workflow in which pre-methylated 5mC (5-methylcytosine) single-stranded adapters are ligated to heat-denatured cfDNA before bisulfite conversion. This method retains only DNA fragments that are unaltered by bisulfite treatment, resulting in less biased uscfDNA methylation analysis. Using 5mCAdpBS-Seq, uscfDNA had lower levels of DNA methylation (~15%) and was enriched in promoters and CpG islands. Hypomethylated uscfDNA fragments were enriched in upstream transcription start sites (TSSs), and the intensity of enrichment positively affected gene expression of hemopoietic cells. Using tissue-of-origin deconvolution, we inferred that uscfDNA is derived primarily from eosinophils, neutrophils, and monocytes. As proof-of-principle, we show that characteristics of the methylation profile of uscfDNA can distinguish non-small cell lung carcinoma from non-cancer samples. The 5mCAdpBS-Seq workflow is recommended for any cfDNA methylation-based investigations.
2024-03-28 | GSE252088 | GEO
Project description:The goal of the experiment was to uncover novel TTTS biomarkers using microarray gene expression analysis of cell free fetal RNA from the amniotic fluid of TTTS-affected and non-affected pregnant women.
2018-06-01 | E-MTAB-6100 | biostudies-arrayexpress
Project description:Breast cancers of the luminal B subtype are frequent tumors with high proliferation and poor prognosis. Epigenetic alterations have been found in breast tumors and in biological fluids. We aimed to profile the cell-free DNA (cfDNA) methylome of metastatic luminal B breast cancer (LBBC) patients using an epigenomic approach to discover potential noninvasive biomarkers. Plasma cfDNA was analyzed using the Infinium MethylationEpic array (EPIC array) in a cohort of 14 women, including metastatic LBBC patients and healthy controls.
2022-11-16 | GSE214344 | GEO
Project description:Background: Liquid biopsy based on cell free DNA (cfDNA) analysis holds significant promise as a minimally invasive approach for the diagnosis, genotyping and monitoring of solid malignancies. Human tumors release cfDNA in the bloodstream through a combination of events, including cell death, active and passive release. However, the precise mechanisms leading to cfDNA shedding remain to be characterized. Addressing this question in patients is confounded by several factors, such as tumor burden extent, anatomical and vasculature barriers, release of nucleic acids from normal cells. In this work, we exploited cancer models to dissect basic mechanisms of DNA release. Methods: We measured cell loss ratio, doubling time and cfDNA release in the supernatant of a colorectal cancer (CRC) cell line collection (N=76) representative of the molecular subtypes previously identified in cancer patients. Association analyses between quantitative parameters of cfDNA release, cell proliferation and molecular features were evaluated. Functional experiments were performed to test the impact of modulating DNA methylation on cfDNA release. Results: Higher levels of supernatant cfDNA were significantly associated with slower cell cycling and increased cellular crashes. In addition, a higher cfDNA shedding was found in non-CpG Island Methylator Phenotype (CIMP) models. These results indicate a positive correlation between lower methylation and increased cfDNA levels. To explore this further, we exploited methylation microarrays to identify a subset of probes significantly associated with cfDNA shedding and derive a methylation signature capable of discriminating high from low cfDNA releasers. We applied this signature to an independent set of 176 CRC cell lines and patient derived organoids to select 14 models predicted to be low or high releasers. The methylation profile successfully predicted the amount of cfDNA released in the supernatant. At the functional level, genetic ablation of DNA methyl-transferases increased chromatin accessibility and DNA fragmentation, leading to increased cfDNA release in isogenic CRC cell lines. Furthermore, in vitro treatment of five low releaser CRC cells with a demethylating agent was able to induce a significant increase in cfDNA shedding. Conclusion: Methylation status of cancer cell lines contributes to the variability of cfDNA shedding in vitro. Changes in methylation pattern are associated with cfDNA release levels and might be exploited to increase sensitivity of liquid biopsy assays.
2024-09-18 | GSE274189 | GEO
Project description:The amniotic fluid (AF) cell-free (cf) RNA was shown to reflect physiological and pathological processes in pregnancy, but its value in prediction of spontaneous preterm delivery is unknown. Here we profiled cfRNA in AF samples collected from women who underwent transabdominal amniocentesis after an episode of spontaneous preterm labor and subsequently delivered within 24h (n=10) or later (n=28) in gestation. Expression of known placental single cell (sc) RNA-Seq signatures were quantified in AF cfRNA and compared between groups. Random forest models were applied to predict time to delivery after amniocentesis. There were 2385 genes differentially expressed in AF samples of women who delivered within 24 hours of amniocentesis compared to gestational age-matched samples from women who delivered after 24 hours of amniocentesis.Genes with cfRNA changes were associated with immune and inflammatory processes related to the onset of labor, and expression of placental scRNA-Seq signatures of immune cells were increased with imminent delivery. AF transcriptomic prediction models captured these effects and predicted delivery within 24 hours of amniocentesis (AUROC =0.81). These results may inform development of biomarkers for spontaneous preterm birth.
2021-10-01 | GSE166956 | GEO