Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA95215 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Gastrointestinal stromal tumors (GISTs) are the most important mesenchymal tumors of the gastrointestinal tract. The vast majority of GISTs exhibit activating mutations of KIT or PDGFRA, but epigenetic alteration of GISTs is largely unknown. In this study, we aimed to clarify the involvement of DNA methylation in GIST malignancy. A total of 25 GIST specimens were studied using Human Genome CGH Microarray Kit 105A (G4412A, Agilent). Levels of LINE-1 methylation were analyzed using bisulfite-pyrosequencing. LINE-1 hypomethylation was correlated with risk grade, and high-risk GISTs exhibited lower levels of LINE-1 methylation than low- or intermediate-risk GISTs. Array CGH analysis revealed a significant correlation between LINE-1 hypomethylation and chromosomal aberrations. Our data suggest that LINE-1 hypomethylation correlates with the aggressiveness of GISTs. Hypomethylation may increase the malignant potential of GISTs by inducing accumulation of chromosomal aberrations.
2010-06-20 | GSE22185 | GEO
Project description:Gastrointestinal stromal tumors (GISTs) are the most important mesenchymal tumors of the gastrointestinal tract. The vast majority of GISTs exhibit activating mutations of KIT or PDGFRA, but epigenetic alteration of GISTs is largely unknown. In this study, we aimed to clarify the involvement of DNA methylation in GIST malignancy. A total of 25 GIST specimens were studied using Human Genome CGH Microarray Kit 105A (G4412A, Agilent). Levels of LINE-1 methylation were analyzed using bisulfite-pyrosequencing. LINE-1 hypomethylation was correlated with risk grade, and high-risk GISTs exhibited lower levels of LINE-1 methylation than low- or intermediate-risk GISTs. Array CGH analysis revealed a significant correlation between LINE-1 hypomethylation and chromosomal aberrations. Our data suggest that LINE-1 hypomethylation correlates with the aggressiveness of GISTs. Hypomethylation may increase the malignant potential of GISTs by inducing accumulation of chromosomal aberrations. A total of 25 surgically obtained human gastrointestinal stromal tumors (GISTs) was analyzed using Agilent CGH microarray. Copy number aberration was compared with clinicopathological features and DNA methylation status.
2010-06-20 | E-GEOD-22185 | biostudies-arrayexpress
Project description:KIT, PDGFRA, NF1, and SDH mutations are alternate initiating events, fostering hyperplasia in gastrointestinal stromal tumors (GISTs), and additional genetic alterations are required for progression to malignancy. The most frequent secondary alteration, demonstrated in ~70% of GISTs, is chromosome 14q deletion. Here we report hemizygous or homozygous inactivating mutations of the chromosome 14q MAX gene in 16 of 76 GISTs (21%). We find MAX mutations in 17% and 50% of sporadic and NF1-syndromic GISTs, respectively, and we find loss of MAX protein expression in 48% and 90% of sporadic and NF1-syndromic GISTs, and in 3 of 8 micro GISTs, which are early GISTs. MAX genomic inactivation is associated with p16 silencing in the absence of p16 coding sequence deletion, and MAX induction restores p16 expression and inhibits GIST proliferation. Hence, MAX inactivation is a common event in GIST progression, fostering cell cycle activity in early GISTs.
2017-02-03 | GSE93077 | GEO
Project description:Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. Current tyrosine kinase inhibitors (TKIs) targeting oncogenic KIT and PDGFRA have improved patient outcomes, yet off-target toxicities and drug resistance mutations remain major clinical challenges. Many approved TKIs, often repurposed from other cancer indications, harbor diverse hinge-binding motifs that limit activity against resistance mutations clustering in the ATP-binding pocket of the kinase domain. Here, we describe a structure-based scaffold-hopping strategy to design novel inhibitors with selectivity for mutant KIT/PDGFRA. Using structure-activity relationship (SAR) studies and 14 newly determined co-crystal structures, including the first structure of the PDGFRA-G680R solvent-front mutation, we define key molecular interactions underlying resistance and inhibitor selectivity. Our lead 6,7-quinazolinebased inhibitors show high potency against clinically relevant KIT/PDGFRA mutations and effectively suppress downstream signaling. These compounds provide selective chemical tools to interrogate resistance mechanisms, and the PDGFRA-G680R structure offers new insights for targeting solvent-front mutations across oncogenic kinases.
2026-08-03 | PXD077574 | Pride
Project description:In addition to KIT and PDGFRA mutations, sequential accumulation of other genetic events is involved in the development and progression of gastrointestinal stromal tumors (GISTs). Until recently, the significance of these other alterations has not been thoroughly investigated. The combination of gene expression profiling and high-resolution genomic copy number analysis offers a detailed molecular portrait of GISTs, providing an essential comprehensive knowledge necessary to guide the discovery of novel target genes involved in tumor development and progression. Fresh tissue specimens from 25 patients with GIST were collected and high-resolution genomic copy number analyses were performed using Affymetrix SNP array 6.0.
2010-08-27 | GSE20709 | GEO
Project description:In addition to KIT and PDGFRA mutations, sequential accumulation of other genetic events is involved in the development and progression of gastrointestinal stromal tumors (GISTs). Until recently, the significance of these other alterations has not been thoroughly investigated. The combination of gene expression profiling and high-resolution genomic copy number analysis offers a detailed molecular portrait of GISTs, providing an essential comprehensive knowledge necessary to guide the discovery of novel target genes involved in tumor development and progression. Fresh tissue specimens from 25 patients with GIST were collected and gene expression profiling was performed using Affymetrix U133Plus array.
2010-08-27 | GSE20708 | GEO
Project description:In addition to KIT and PDGFRA mutations, sequential accumulation of other genetic events is involved in the development and progression of gastrointestinal stromal tumors (GISTs). Until recently, the significance of these other alterations has not been thoroughly investigated. The combination of gene expression profiling and high-resolution genomic copy number analysis offers a detailed molecular portrait of GISTs, providing an essential comprehensive knowledge necessary to guide the discovery of novel target genes involved in tumor development and progression. Fresh tissue specimens from 25 patients with GIST were collected and high-resolution genomic copy number analyses were performed using Affymetrix SNP array 6.0. GIST tumor samples from mutated (KIT or PDGFRA) or Wild Type patients were labeled for hybridization on Affymetrix microarrays. Copy number analysis of Affymetrix SNP6.0 arrays was performed for 25 GIST samples, then compared to gene expression data.
2010-08-27 | E-GEOD-20709 | biostudies-arrayexpress
Project description:<p>Metabolic lesions with pleiotropic effects on epigenetic regulation and other cellular processes are widely implicated in cancer, yet their oncogenic mechanisms remain poorly understood. Succinate dehydrogenase (SDH) deficiency causes a subset of gastrointestinal stromal tumors (GISTs) with DNA hyper-methylation. Here we associate this hyper-methylation with changes in chromosome topology that activate oncogenic programs. To investigate epigenetic alterations in this disease, we systematically mapped DNA methylation, CTCF insulators, enhancers and chromosome topology in KIT-mutant, PDGFRA-mutant and SDH-deficient GISTs. Although these respective subtypes share similar enhancer landscapes, we identified hundreds of putative insulators where DNA methylation replaced CTCF binding in SDH-deficient GISTs. We focused on disrupted insulators that partitions super-enhancers from FGF3, FGF4 and the KIT oncogene. Recurrent loss of this insulator alters locus topology in SDH-deficient GISTs, allowing aberrant physical interaction between enhancers and oncogenes. CRISPR-mediated excision of the corresponding CTCF motif in an SDH-intact model disrupted the boundary and up-regulated FGFs and KIT expression. Our findings reveal how a metabolic lesion destabilizes chromatin structure to facilitate the initiation and selection of epigenetic alterations that drive oncogenic programs in the absence of canonical mutations.</p>
| phs001906 | dbGaP
Project description:Gastrointestinal stromal tumours (GISTs) represent a heterogeneous group of tumours of mesenchymal origin characterized by gain-of-function mutations in KIT or PDGFRA of the type III receptor tyrosine kinase family. Although mutations in either receptor are thought to drive an early oncogenic event through similar pathways, two previous studies reported the mutation-specific gene expression profiles. However, their further conclusions were rather discordant. To clarify the molecular characteristics of differentially expressed genes according to GIST receptor mutations, we combined microarray-based analysis with detailed functional annotations. Experiment Overall Design: 29 samples: 15 with KIT mutation detected, 11 with PDGFRA mutation detected, 3 with no mutation detected
2009-09-05 | E-GEOD-17743 | biostudies-arrayexpress
Project description:The CD117 mast/stem cell growth factor receptor tyrosine kinase (KIT) is critical for haematopoiesis, melanogenesis, and stem cell maintenance. KIT is commonly activated by mutation in cancers including acute myeloid leukaemia, melanoma, and gastrointestinal stromal tumours (GISTs). The kinase and the juxtamembrane domains of KIT are mutation hotspots; with the kinase domain mutation D816V common in leukaemia, and the juxtamembrane domain mutation V560G common in GISTs. Given the importance of mutant KIT signalling in cancer, we have conducted a proteomic and phosphoproteomic analysis of D816V- and V560G-KIT mutations, using an FDCP1 isogenic cell line model.
2025-06-19 | PXD043783 | Pride