Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA369358 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:SMARCB1 (Snf5/Ini1/Baf47) is a potent tumor suppressor, the loss of which serves as the diagnostic feature in Malignant Rhabdoid Tumors (MRT) and Atypical Teratoid/Rhabdoid Tumors (AT/RT), two highly aggressive forms of pediatric neoplasms. Here, we restore Smarcb1 expression in cells derived from Smarcb1-deficient tumors which developed in Smarcb1-heterozygous p53-/- mice. Profiling Smarcb1 dependent gene expression we find genes which are dependent on Smarcb1 expression to be enriched for ECM and cell adhesion functions. We identify Igfbp7, which is related to the insulin-like growth factor binding proteins family, as a downstream target of Smarcb1 transcriptional activity, and show that re-introduction of Igfbp7 alone can hinder tumor development. Two cancer cell lines, 167 and 365, derived from Smarcb1-deficient tumors which developed in Smarcb1-heterozygous p53-/- mice were re-infected with a retro-viral vector for Smarcb1 re-expression or an empty retro-viral vector as control. Total-RNA was collected 3 days post infection so as to enrich for direct targets of Smarcb1 transcriptionaly regulated genes
2013-12-31 | E-GEOD-46017 | biostudies-arrayexpress
Project description:SMARCB1 (Snf5/Ini1/Baf47) is a potent tumor suppressor, the loss of which serves as the diagnostic feature in Malignant Rhabdoid Tumors (MRT) and Atypical Teratoid/Rhabdoid Tumors (AT/RT), two highly aggressive forms of pediatric neoplasms. Here, we restore Smarcb1 expression in cells derived from Smarcb1-deficient tumors which developed in Smarcb1-heterozygous p53-/- mice. Profiling Smarcb1 dependent gene expression we find genes which are dependent on Smarcb1 expression to be enriched for ECM and cell adhesion functions. We identify Igfbp7, which is related to the insulin-like growth factor binding proteins family, as a downstream target of Smarcb1 transcriptional activity, and show that re-introduction of Igfbp7 alone can hinder tumor development.
2013-12-31 | GSE46017 | GEO
Project description:Rhabdoid Tumors (RT) are highly aggressive tumors that are frequently localized in the central nervous system (CNS) where they are termed atypical teratoid and rhabdoid tumors (ATRT). We generated conditional Smarcb1-deficient mouse model leads to CNS Smarcb1-deficient tumors. We used microarrays to compared gene expression profilings of various human and mouse tumors. Our data demonstrate that the Smarcb1-deficient mouse model recapitulates the diversity of human RT.
2016-01-27 | GSE64019 | GEO
Project description:Germline mutations of the SMARCB1 gene predispose to two distinct tumor syndromes: rhabdoid tumor predisposition syndrome, with malignant pediatric tumors mostly developing in brain and kidney, and familial schwannomatosis, with adulthood benign tumors involving cranial and peripheral nerves. The mechanisms by which SMARCB1 germline mutations predispose to rhabdoid tumors versus schwannomas are still unknown. Here, to understand the origin of these two types of SMARCB1-associated tumors, we generated different tissue- and developmental stage-specific conditional knockout mice carrying Smarcb1 and/or Nf2 deletion. Smarcb1 loss in early neural crest was necessary to initiate tumorigenesis in the cranial nerves and meninges with typical histological features and molecular profiles of human rhabdoid tumors. By inducing Smarcb1 loss at later developmental stage in the Schwann cell lineage, in addition to biallelic Nf2 gene inactivation, we generated the first mouse model developing schwannomas with the same underlying gene mutations found in schwannomatosis patients.
2017-10-31 | GSE94082 | GEO
Project description:Loss of function mutations in SMARCB1 are prevalent in pediatric atypical teratoid rhabdoid tumors (ATRTs) and confer an oncogenic dependency on EZH2, providing a compelling rationale for treating these genetically defined cancers via EZH2 inhibition (EZH2i). EZH2i results in tumor regression in SMARCB1-deficient tumors in preclinical studies, but the molecular mechanism has not been fully elucidated. Here we found that the sensitivity of SMARCB1-deficient tumors to EZH2i is associated with the viral mimicry response that depends on both double-stranded RNA (dsRNA) and cytoplasmic DNA sensing pathways. Unlike other epigenetic therapies targeting transcriptional repressors, viral mimicry by EZH2i in SMARCB1-deficient tumors is not triggered by crypt initiation of endogenous retroelements, but rather mediated by increased expression of genes enriched for intronic inverted-repeat Alu (IR-Alu) elements. Interestingly, we found that interferon-stimulated genes (ISGs) are highly enriched for dsRNA-forming intronic IR-Alu elements, suggesting a positive feedback loop whereby interferon response leads to dsRNA formation from intronic ISGs and activation of viral mimicry. Moreover, EZH2i in ATRT cells also enhances the expression of full-length LINE-1 elements, leading to genomic instability and cGAS/STING response in a process dependent on reverse transcriptase activity. Supporting this mechanism, co-depletion of dsRNA sensing and cytoplasmic DNA sensing completely rescues the viral mimicry response to EZH2i in SMARCB1-deficient tumors.
2024-09-05 | GSE213248 | GEO
Project description:Loss of function mutations in SMARCB1 are prevalent in pediatric atypical teratoid rhabdoid tumors (ATRTs) and confer an oncogenic dependency on EZH2, providing a compelling rationale for treating these genetically defined cancers via EZH2 inhibition (EZH2i). EZH2i results in tumor regression in SMARCB1-deficient tumors in preclinical studies, but the molecular mechanism has not been fully elucidated. Here we found that the sensitivity of SMARCB1-deficient tumors to EZH2i is associated with the viral mimicry response that depends on both double-stranded RNA (dsRNA) and cytoplasmic DNA sensing pathways. Unlike other epigenetic therapies targeting transcriptional repressors, viral mimicry by EZH2i in SMARCB1-deficient tumors is not triggered by crypt initiation of endogenous retroelements, but rather mediated by increased expression of genes enriched for intronic inverted-repeat Alu (IR-Alu) elements. Interestingly, we found that interferon-stimulated genes (ISGs) are highly enriched for dsRNA-forming intronic IR-Alu elements, suggesting a positive feedback loop whereby interferon response leads to dsRNA formation from intronic ISGs and activation of viral mimicry. Moreover, EZH2i in ATRT cells also enhances the expression of full-length LINE-1 elements, leading to genomic instability and cGAS/STING response in a process dependent on reverse transcriptase activity. Supporting this mechanism, co-depletion of dsRNA sensing and cytoplasmic DNA sensing completely rescues the viral mimicry response to EZH2i in SMARCB1-deficient tumors.
2024-09-05 | GSE213249 | GEO
Project description:SMARCB1 (SNF5/INI1/BAF47), a core subunit of the SWI/SNF (BAF) chromatin remodeling complex, is inactivated in nearly all pediatric rhabdoid tumors. These aggressive cancers are among the most genomically stable, suggesting an epigenetic mechanism by which SMARCB1 loss drives transformation. Here, we show that despite indistinguishable mutational landscapes, human RTs show distinct enhancer H3K27ac signatures, which reveal remnants of differentiation programs. We show that SMARCB1 is required for the integrity of SWI/SNF complexes and that its loss alters enhancer targeting markedly impairing SWI/SNF binding to typical enhancers, particularly those required for differentiation, while maintaining SWI/SNF binding at super-enhancers. We show that these retained super-enhancers are essential for rhabdoid tumor survival, including some that are shared across all subtypes, such as SPRY1, and other lineage-specific super-enhancers like SOX2 in brain-derived RTs. Taken together, our findings reveal a novel chromatin-based epigenetic mechanism underlying the tumor suppressive activity of SMARCB1.
2016-11-21 | GSE71505 | GEO
Project description:SMARCB1 (SNF5/INI1/BAF47), a core subunit of the SWI/SNF (BAF) chromatin remodeling complex, is inactivated in nearly all pediatric rhabdoid tumors. These aggressive cancers are among the most genomically stable, suggesting an epigenetic mechanism by which SMARCB1 loss drives transformation. Here, we show that despite indistinguishable mutational landscapes, human RTs show distinct enhancer H3K27ac signatures, which reveal remnants of differentiation programs. We show that SMARCB1 is required for the integrity of SWI/SNF complexes and that its loss alters enhancer targeting markedly impairing SWI/SNF binding to typical enhancers, particularly those required for differentiation, while maintaining SWI/SNF binding at super-enhancers. We show that these retained super-enhancers are essential for rhabdoid tumor survival, including some that are shared across all subtypes, such as SPRY1, and other lineage-specific super-enhancers like SOX2 in brain-derived RTs. Taken together, our findings reveal a novel chromatin-based epigenetic mechanism underlying the tumor suppressive activity of SMARCB1.
2016-11-21 | GSE71504 | GEO
Project description:SMARCB1 (SNF5/INI1/BAF47), a core subunit of the SWI/SNF (BAF) chromatin remodeling complex, is inactivated in nearly all pediatric rhabdoid tumors. These aggressive cancers are among the most genomically stable, suggesting an epigenetic mechanism by which SMARCB1 loss drives transformation. Here, we show that despite indistinguishable mutational landscapes, human RTs show distinct enhancer H3K27ac signatures, which reveal remnants of differentiation programs. We show that SMARCB1 is required for the integrity of SWI/SNF complexes and that its loss alters enhancer targeting markedly impairing SWI/SNF binding to typical enhancers, particularly those required for differentiation, while maintaining SWI/SNF binding at super-enhancers. We show that these retained super-enhancers are essential for rhabdoid tumor survival, including some that are shared across all subtypes, such as SPRY1, and other lineage-specific super-enhancers like SOX2 in brain-derived RTs. Taken together, our findings reveal a novel chromatin-based epigenetic mechanism underlying the tumor suppressive activity of SMARCB1.
2016-11-21 | GSE71503 | GEO
Project description:SMARCB1 (SNF5/INI1/BAF47), a core subunit of the SWI/SNF (BAF) chromatin remodeling complex, is inactivated in nearly all pediatric rhabdoid tumors. These aggressive cancers are among the most genomically stable, suggesting an epigenetic mechanism by which SMARCB1 loss drives transformation. Here, we show that despite indistinguishable mutational landscapes, human RTs show distinct enhancer H3K27ac signatures, which reveal remnants of differentiation programs. We show that SMARCB1 is required for the integrity of SWI/SNF complexes and that its loss alters enhancer targeting markedly impairing SWI/SNF binding to typical enhancers, particularly those required for differentiation, while maintaining SWI/SNF binding at super-enhancers. We show that these retained super-enhancers are essential for rhabdoid tumor survival, including some that are shared across all subtypes, such as SPRY1, and other lineage-specific super-enhancers like SOX2 in brain-derived RTs. Taken together, our findings reveal a novel chromatin-based epigenetic mechanism underlying the tumor suppressive activity of SMARCB1.
2016-11-21 | GSE71502 | GEO