Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA169545 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Acute myeloid leukemia (AML) is characterized by molecular heterogeneity. As commonly altered genomic regions point to candidate genes involved in leukemogenesis, we used microarray-based comparative genomic hybridization and single nucleotide polymorphism profiling data of 391 AML cases to further narrow down genomic regions of interest. Targeted-resequencing of 1000 genes located in the critical regions was performed in a representative cohort of 50 AML samples comprising all major cytogenetic subgroups. We identified 120 missense/nonsense mutations as well as 60 insertions/deletions affecting 73 different genes (~3.6 tumor-specific aberrations/AML). While most of the newly identified alterations were non-recurrent, we observed a number of mutations affecting genes involved in epigenetic regulation including known candidates like TET2, TET1, DNMT3A and DNMT1, as well as mutations in the histone methyltransferases NSD1, EZH2 and MLL3. Furthermore, we found mutations in the splicing factor SFPQ and in the non-classical regulators of mRNA-processing CTCF and RAD21. These splicing-related mutations affected 10% of AML patients in a mutually exclusive manner. In conclusion, we could identify a significant enrichment of alterations in genes involved in aberrant splicing and epigenetic regulation in genomic regions commonly altered in AML, highlighting their important role in the molecular pathogenesis of AML. All samples were obtained from untreated patients at the time of diagnosis. Cells used for microarray analysis were collected from the purified fraction of mononuclear cells after Ficoll density centrifugation.
2012-09-27 | E-GEOD-38987 | biostudies-arrayexpress
Project description:Acute myeloid leukemia (AML) is characterized by molecular heterogeneity. As commonly altered genomic regions point to candidate genes involved in leukemogenesis, we used microarray-based comparative genomic hybridization and single nucleotide polymorphism profiling data of 391 AML cases to further narrow down genomic regions of interest. Targeted-resequencing of 1000 genes located in the critical regions was performed in a representative cohort of 50 AML samples comprising all major cytogenetic subgroups. We identified 120 missense/nonsense mutations as well as 60 insertions/deletions affecting 73 different genes (~3.6 tumor-specific aberrations/AML). While most of the newly identified alterations were non-recurrent, we observed a number of mutations affecting genes involved in epigenetic regulation including known candidates like TET2, TET1, DNMT3A and DNMT1, as well as mutations in the histone methyltransferases NSD1, EZH2 and MLL3. Furthermore, we found mutations in the splicing factor SFPQ and in the non-classical regulators of mRNA-processing CTCF and RAD21. These splicing-related mutations affected 10% of AML patients in a mutually exclusive manner. In conclusion, we could identify a significant enrichment of alterations in genes involved in aberrant splicing and epigenetic regulation in genomic regions commonly altered in AML, highlighting their important role in the molecular pathogenesis of AML.
2012-09-27 | GSE38987 | GEO
Project description:Most cases of adult myeloid neoplasms are routinely assumed to be sporadic. Here, we describe an adult familial acute myeloid leukemia (AML) syndrome caused by germline mutations in the DEAD/H-Box helicase gene DDX41. DDX41 was also found to be affected by somatic mutations in sporadic cases of myeloid neoplasms as well as in a biallelic fashion in 50% of patients with germline DDX41 mutations. Moreover, corresponding deletions on 5q35.3 present in 6% of cases lead to haploinsufficient DDX41 expression. DDX41 lesions caused altered pre-mRNA splicing and RNA processing. DDX41 is exemplary of other RNA helicase genes also affected by somatic mutations, suggesting that they constitute a family of tumor suppressor genes. Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from cryopreserved diagnostic bone marrow or peripheral blood samples.
2015-04-01 | E-GEOD-66668 | biostudies-arrayexpress
Project description:Most cases of adult myeloid neoplasms are routinely assumed to be sporadic. Here, we describe an adult familial acute myeloid leukemia (AML) syndrome caused by germline mutations in the DEAD/H-Box helicase gene DDX41. DDX41 was also found to be affected by somatic mutations in sporadic cases of myeloid neoplasms as well as in a biallelic fashion in 50% of patients with germline DDX41 mutations. Moreover, corresponding deletions on 5q35.3 present in 6% of cases lead to haploinsufficient DDX41 expression. DDX41 lesions caused altered pre-mRNA splicing and RNA processing. DDX41 is exemplary of other RNA helicase genes also affected by somatic mutations, suggesting that they constitute a family of tumor suppressor genes.
2015-04-01 | GSE66668 | GEO
Project description:Acute Myeloid Leukemia (AML) has been associated with somatic mutations in numerous genes; however, the penetrance of these mutations is low. Here we investigate the contribution of alternative splicing as an additional layer of gene dysregulation in AML. By analyzing splicing variations across two patient datasets, we find a consistent set of splicing events that disrupt the coding potential of a subset of AML-associated genes. Importantly, most of these splicing variations are independent of any currently-identified somatic mutations. We have further validated that for EZH2 and ZRSR2 these splicing events reduce the expression of full-length protein. Together these results highlight the contribution of splicing to gene dysregulation and demonstrate that mutation analysis underestimates the burden of functional gene disruption in patient populations.
2021-04-01 | GSE142514 | GEO
Project description:RNA-binding proteins (RBPs) are essential modulators of transcription and translation and are often dysregulated in cancer. Here we systematically interrogated RBP vulnerabilities in acute myeloid leukemia (AML) by performing a comprehensive CRISPR/Cas9 screen, targeting the RNA-binding domains of all classical RBPs. Our screen revealed RBPs that are exclusively required for leukemia survival, including the splicing factor RBM39. Proteomics analysis identified a network of RBP’s interacting with RBM39 crucial for maintaining RNA splicing and survival in AML. Mechanistically, RBM39 suppression led to altered splicing of genes involved in essential oncogenic pathways. Selective targeting of RBM39 via ubiquitin-mediated pharmacologic degradation induced broad anti-leukemic effects in vitro and potent single agent activity in vivo. The effects of RBM39 loss on alteration of splicing further resulted in preferential lethality of AML cells bearing spliceosomal gene mutations, thereby providing a strategy for treating AML patients bearing RBP splicing mutations.
2019-02-25 | GSE114558 | GEO
Project description:Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17) leading to formation of PML-RARA fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, while mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large scale activation of gene expression and reduced in vitro differentiation potential. Studying the effects of silensing ARID1B gene in NB4 cell lines
2016-02-17 | E-GEOD-77946 | biostudies-arrayexpress
Project description:Even though leukemia is considered as confined to one specific hematopoietic cell type, cases of acute leukemia of ambiguous lineage and patients relapsing in phenotypically altered disease suggest that a malignant state may be transferred between lineages. Because B-cell leukemia is associated with mutations in transcription factors of importance for stable preservation of lineage identity we here investigated the potential lineage plasticity of leukemic cells. We report that primary pro-B leukemia cells from mice carrying heterozygous mutations in either of or both the Pax5 and Ebf1 gene, commonly mutated in human leukemia, can be converted into T-lineage leukemia cells. Even though the conversion process involved global changes in gene expression and lineage restricted epigenetic reconfiguration, the malignant phenotype of the cells was preserved enabling them to expand as T-lineage leukemia cells in vivo. Furthermore, while the transformed pro-B cells displayed plasticity towards myeloid lineages, the converted cells failed to cause myeloid leukemia after transplantation. These data provide evidence that a malignant phenotype can be transferred between hematopoietic lineages. This has important implications for modern cancer medicine because lineage targeted treatment of leukemia patients can be predicted to provoke the emergence of phenotypically altered sub-clones causing clinical relapse.
2016-12-20 | GSE90655 | GEO
Project description:Mutations in RNA splicing factors are prevalent across cancers and generate recurrently mis-spliced mRNA isoforms. Here we identified a series of bona fide neoantigens translated from highly stereotyped splicing alterations promoted by neomorphic, leukemia-associated somatic mutations in the splicing machinery. We utilized feature-barcoded peptide-MHC dextramers to isolate neoantigen-specific T cell receptors (TCR) from both healthy donors and patients with leukemia. While circulating neoantigen-specific CD8+ T cells were identified in patients with active disease, they were dysfunctional with reduced inflammatory response gene signatures. In contrast, donor CD8+ T cells with tumor-reactive TCRs were present following curative allogeneic hematopoietic cell transplant. T cells engineered with TCRs recognizing an SRSF2 mutant-induced neoantigen in CLK3 resulted in specific recognition and cytotoxicity of SRSF2 mutant leukemia. These data identify RNA mis-splicing derived neoantigens and neoantigen-specific TCRs across patients and provide proof-of-concept to genetically redirect T cells to public mis-splicing derived neoantigens in myeloid leukemias.
2024-05-22 | GSE268157 | GEO
Project description:Mutations in genes encoding splicing factors (which we refer to as spliceosomal genes) are commonly found in patients with myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). These mutations recurrently affect specific amino acid residues, leading to perturbed normal splice site and exon recognition. Spliceosomal gene mutations are always heterozygous and rarely occur together with one another, suggesting that cells may tolerate only a partial deviation from normal splicing activity. To test this hypothesis, we engineered mice to express a mutated allele of serine/arginine-rich splicing factor 2 (Srsf2P95H) - which commonly occurs in individuals with MDS and AML - in an inducible, hemizygous manner in hematopoietic cells. These mice rapidly succumbed to fatal bone marrow failure, demonstrating that Srsf2-mutated cells depend on the wild-type Srsf2 allele for survival. In the context of leukemia, treatment with the spliceosome inhibitor E7107 resulted in substantial reductions in leukemic burden, specifically in isogenic mouse leukemias and patient-derived xenograft AMLs carrying spliceosomal mutations. Whereas E7107 treatment of mice resulted in widespread intron retention and cassette exon-skipping in leukemic cells regardless of Srsf2 genotype, the magnitude of splicing inhibition following E7107 treatment was greater in Srsf2-mutated than in Srsf2-wild-type leukemia, consistent with the differential effect of E7107 on survival. Collectively, these data provide genetic and pharmacologic evidence that leukemias with spliceosomal gene mutations are preferentially susceptible to additional splicing perturbations in vivo as compared to leukemias without such mutations. Modulation of spliceosome function may thus provide a new therapeutic avenue in genetically defined subsets of individuals with MDS or AML.
2016-03-31 | GSE74064 | GEO