CEHM
Ontology highlight
ABSTRACT:
PROVIDER: EGAS00001002366 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Clonal and subclonal evolution is involved in the progression of chronic lymphocytic leukemia (CLL). Evolution can work to select not only genetic mutations, but also epigenetic states. Here we performed a long-term longitudinal DNA methylation profiling study of CLL patients to look for associations of epigenetic evolution to different disease courses. In line with the genetic data, large-scale methylation evolution was not present in any of the evaluated long-term untreated (n = 3) and relapsed (n = 2) patients displaying clonal changes of linear type while 3 of the 5 examined refractory patients featured profound changes in DNA methylation.
2021-03-15 | GSE143411 | GEO
Project description:Recurrences of diffuse large B-cell lymphomas (DLBCL) result in significant morbidity and mortality, but their underlying genetic and biological mechanisms are unclear. Clonal relationship in DLBCL relapses so far is mostly addressed by the investigation of immunoglobulin (IG) rearrangements, therefore lacking deeper insights into genome-wide lymphoma evolution. We studied mutations and copy number aberrations in 20 paired relapsing and 20 non-relapsing DLBCL cases aiming to test the clonal relationship between primaries and relapses, to track tumors’ genetic evolution and to investigate the genetic background of DLBCL recurrence. Three clonally-unrelated DLBCL relapses were identified (15%). Also, two distinct patterns of genetic evolution in clonally-related relapses were detected: (1) early-divergent/branching evolution from a common progenitor in 6 patients (30%), and (2) late-divergent/linear progression of relapses in 11 patients (65%). Analysis of recurrent genetic events identified potential early drivers of lymphomagenesis (KMT2D, MYD88, CD79B and PIM1). The most frequent relapse-specific events were additional mutations in KMT2D and alterations of MEF2B. SOCS1 mutations were exclusive to non-relapsing DLBCL, whereas primaries of relapsing DLBCL more commonly displayed gains of 10p15.3-p12.1 containing the potential oncogenes PRKCQ, GATA3, MLLT10 and ABI1. Altogether, our study expands knowledge on clonal relationship, genetic evolution and mutational basis of DLBCL relapses.
2016-06-01 | GSE65720 | GEO
Project description:Hereditary endocrine neoplasias, including phaeochromocytoma/paraganglioma (PPGL) and medullary thyroid cancer (MTC), are caused by autosomal dominant mutations in a multitude of familial cancer genes. A common feature of these diseases is the presentation of multiple primary tumours or multifocal disease representing independent tumour clones that have arisen from the same initiating genetic lesion but have undergone independent clonal evolution. Such tumours provide a unique opportunity to discover common co-operative changes required for tumorigenesis while controlling for the genetic background of the individual. We performed an in-depth genomic analysis of synchronous and metachronous tumours from five patients harbouring germline mutations in the genes SDHB, RET and MAX. Using whole exome sequencing and high-density SNP-arrays we analyzed between two and four primary tumours from each patient. Furthermore, we applied multi-regional sampling to assess intra-tumoral heterogeneity and clonal evolution in two cases involving PPGL and MTC, respectively. Heterogeneous patterns of genomic change existed between synchronous or metachronous tumours with evidence of branching evolution. We observed striking examples of evolutionary convergence involving the same rare somatic copy-number events in synchronous primary PPGL. Convergent events also occurred during clonal evolution of metastatic MTC. These observations suggest that genetic or epigenetic changes acquired early within precursor cells, or pre-existing within the genetic background of the individual, create contingencies that determine the evolutionary trajectory of the tumour.
2017-02-02 | GSE94378 | GEO
Project description:To study longitudinal dynamics of IGH BCR repertoires and clonal lineages evolution of memory B-cells, plasmablasts and plasma cells from peripheral blood of healthy donors, which were sampled three times within a year
2022-09-15 | E-MTAB-11193 | biostudies-arrayexpress
Project description:<p>Hematopoietic stem cell (HSC) mutations can result in clonal hematopoiesis (CH) with heterogeneous clinical outcomes. Here, we investigated how the cell state preceding <em>Tet2</em> mutation impacts the pre-malignant phenotype. Using an inducible system for clonal analysis of myeloid progenitors, we found that the epigenetic features of clones at similar differentiation status were highly heterogeneous and functionally responded differently to <em>Tet2</em> mutation. Cell differentiation stage also influenced <em>Tet2</em> mutation response indicating that the cell of origin's epigenome modulates clone-specific behaviors in CH. Molecular features associated with higher risk outcomes include <em>Sox4</em> that sensitized cells to <em>Tet2</em> inactivation, inducing dedifferentiation, altered metabolism and increasing the <em>in vivo</em> clonal output of mutant cells, as confirmed in primary GMP and HSC models. Our findings validate the hypothesis that epigenetic features can predispose specific clones for dominance, explaining why identical genetic mutations can result in different phenotypes.</p>
2024-04-30 | MTBLS9914 | MetaboLights
Project description:Recurrences of diffuse large B-cell lymphomas (DLBCL) result in significant morbidity and mortality, but their underlying genetic and biological mechanisms are unclear. Clonal relationship in DLBCL relapses so far is mostly addressed by the investigation of immunoglobulin (IG) rearrangements, therefore lacking deeper insights into genome-wide lymphoma evolution. We studied mutations and copy number aberrations in 20 paired relapsing and 20 non-relapsing DLBCL cases aiming to test the clonal relationship between primaries and relapses, to track tumorsâ genetic evolution and to investigate the genetic background of DLBCL recurrence. Three clonally-unrelated DLBCL relapses were identified (15%). Also, two distinct patterns of genetic evolution in clonally-related relapses were detected: (1) early-divergent/branching evolution from a common progenitor in 6 patients (30%), and (2) late-divergent/linear progression of relapses in 11 patients (65%). Analysis of recurrent genetic events identified potential early drivers of lymphomagenesis (KMT2D, MYD88, CD79B and PIM1). The most frequent relapse-specific events were additional mutations in KMT2D and alterations of MEF2B. SOCS1 mutations were exclusive to non-relapsing DLBCL, whereas primaries of relapsing DLBCL more commonly displayed gains of 10p15.3-p12.1 containing the potential oncogenes PRKCQ, GATA3, MLLT10 and ABI1. Altogether, our study expands knowledge on clonal relationship, genetic evolution and mutational basis of DLBCL relapses. There are 62 copy number Agilent 180k SurePrint arrays in total, which represent 40 cases. There are 21 arrays of primary relapsing DLBCL tumors, 21 arrys of matched relapses and 20 arrays of non relapsing DLBCLs.
2016-06-01 | E-GEOD-65720 | biostudies-arrayexpress
Project description:Cutaneous T cell lymphoma (CTCL) is a heterogeneous group of mature T cell neoplasms characterized by the accumulation of clonal malignant CD4+ T cells in the skin. The most common variant of CTCL, Mycosis Fungoides, is confined to the skin in early stages but can be accompanied by extracutaneous dissemination of malignant T cells to the blood and lymph nodes in advanced stages of disease. Sézary Syndrome, a leukemic form of disease is characterized by significant blood involvement. Little is known about the transcriptional and genomic relationship between skin and blood residing malignant T cells in CTCL. In the present study we interrogate multiple modalities of information in single cells from matched skin and blood samples of patients with leukemic disease and healthy controls within a single workflow. By employing expanded CRISPR-compatible cellular indexing of transcriptomes and epitopes by sequencing (ECCITE-seq), we sought to compare the molecular profile of malignant clones residing in the skin and circulation of these patients across gene and protein expression modalities. We apply inferred CNV and phylogenetic analysis to examine sub-clonal heterogeneity to gain insights into the evolution and the relationship of malignant clones across tissues. Our data reveals clonal evolution at a transcriptional and genetic level within the malignant populations of individual patients. We highlight highly consistent transcriptional signatures delineating skin-derived and blood-derived malignant T cells. Analysis of these two populations suggests that environmental cues, along with genetic aberrations, contribute to transcriptional profiles of malignant T cells.
2021-07-30 | GSE171811 | GEO
Project description:The progression of many solid tumors is accompanied by temporal and spatial changes in the stiffness of the extracellular matrix (ECM). Cancer cells adapt to soft and stiff ECM through mechanisms that are not fully understood. In particular, it is well known that there is significant genetic heterogeneity from cell to cell in tumors, but how ECM stiffness as a parameter might interact with that genetic variation is not known. Here, we used the method of experimental evolution to study response of genetically variable and clonal tumor cell populations to ECM stiffness. Cell fitness increased on soft ECM over a period of several weeks in genetically variable but not clonal populations. DNA barcode-enabled clonal tracking revealed that sustained culture on soft ECM selects for a few genetic variants. These data provide the first evidence that ECM stiffness exerts natural selection on genetically variable tumor populations. Genome-wide analysis including RNA-seq, ATAC-seq and DNA methylation profiling reveal substantial differences in gene expression between selected populations and ancestral cells which are partially explained by epigenetic modifications. Soft-selected cells are highly migratory with enriched oncogenic signatures and exhibit highly unusual behaviors like spreading and traction force generation on ECMs as soft as 1 kPa. Cell spreading is the directly selected trait but not levels of integrins or adhesion proteins like talin. Overall, these data show that ECM stiffness in solid tumors may drive malignant behaviors through evolution by natural selection.
2026-02-18 | GSE255827 | GEO
Project description:Embryonic genome activation (EGA) marks the onset of embryonic program and enables the transition toward the first lineage specification. However, the molecular features of EGA and the transcription factors (TFs) orchestrating this process remain unclear. Here, by performing single-cell RNA-seq on bovine embryos, we reveal that major EGA is asynchronously initiated among blastomeres at the 8-cell stage. Integrative analyses reveal distinctive protein accumulation compared to transcription and translation activation during bovine EGA. Furthermore, we investigate the role of SP1, a TF activated at the minor EGA stage, with motifs enriched in accessible chromatin during major EGA stage in bovine and human embryos. SP1 deficiency leads to morula arrest in bovine and impairs EGA in human embryos. Multi-omics analysis demonstrates that SP1 promotes early lineage gene expression by modulating nearby chromatin states in bovine and directly targets key EGA genes in human embryos. Together, our study delineates the dynamics of bovine EGA and uncovers the conserved and species-specific roles of SP1 in regulating EGA and early development in mammals.
2026-02-12 | GSE304792 | GEO
Project description:Esophageal squamous cell carcinoma (ESCC) is among the most common malignancies, but little is known about the spatial intratumor heterogeneity (ITH) and the temporal clonal evolutionary processes in this cancer. Interestingly, the epigenetic profiling also showed strong evidence of spatial ITH, and the phyloepigenetic trees were extremely similar with the phylogenetic ones, indicating the interplay and co-dependency of genetic and epigenetic alterations in ESCC. We found that several genes were both mutated and hypermethylated at their promoters, such as ASXL1 and EPHA7. Our integrated investigations of the spatial ITH and the temporal clonal evolution might provide insights into developing biomarkers for early diagnosis of ESCC, as well as personalized therapeutic targets for treating this malignancy. DNA methylation profiles of 12 tumor regions and 2 matched normal esophageal epithelial tissues from three M-WES-examined ESCC cases (ESCC01, ESCC03 and ESCC05) were performed using Illumina Infinium HumanMethylation450K platform (Illumina, San Diego, CA) at the Epigenome Center of University of Southern California.
2016-08-20 | E-GEOD-79366 | biostudies-arrayexpress