04bf693b-1bf0-461f-914f-4b9f830af063 - samples
Ontology highlight
ABSTRACT:
PROVIDER: EGAD00001006202 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Similar to their adult counterparts, the prognosis for pediatric patients with high-grade gliomas remains poor. At time of recurrence, treatment options are limited and remain without consensus. This report describes the genetic findings, obtained from whole exome sequencing of a pediatric patient with glioblastoma who underwent multiple surgical resections and treatment with standard chemoradiation, as well as a novel recombinant poliovirus vaccine therapy. Strikingly, despite the variety of treatments, there was persistence of a tumor clone, characterized by a deleterious STAG2 mutation, whose deficiency in pre-clinical studies can cause aneuploidy and aberrant mitotic progression, but remains understudied in the clinical setting. There was near elimination of an EGFR mutated and amplified tumor clone after gross total resection, standard chemoradiation, and poliovirus therapy, followed by the emergence of a persistently STAG2 mutated clone, with rare mutations in PTPN11 and BRAF, the latter composed of a novel deleterious mutation previously not reported in pediatric glioblastoma (p.D594G). This was accompanied by a mutation signature shift towards one characterized by increased DNA damage repair defects, consistent with the known underlying STAG2 deficiency. As such, this case represents a novel report following the clinical and genetic progression of a STAG2 mutated glioblastoma, including treatment with a novel and emerging immunotherapy. Although STAG2 deficiency comprises only a small subset of gliomas, this case adds clinical evidence to existing pre-clinical data supporting a role for STAG2 mutations in tumor formation and resistance to standard therapies.
| EGAS00001004340 | EGA
Project description:Glioblastoma Patient samples were acquired before and after standard chemoradiation or standard chemoradiation+TTFields (Novo-TTF100) treatment. The set includes paired before-after samples of 6 control patients (chemoradiation) and 6 TTFields+chemoradiation patients.
| EGAD00001007782 | EGA
Project description:Ewing sarcoma is an aggressive malignancy characterized by oncogenic rearrangements of the EWS gene with an ETS-family transcription factor, most commonly FLI. Recent comprehensive next-generation sequencing efforts have revealed few other highly recurrent mutations in this disease apart from loss-of-function mutations in STAG2 which occur in 15-20% of tumors. STAG2 is a member of the cohesin complex, which regulates sister chromatid alignment during mitosis and epigenetic regulation of gene expression. While some studies suggest that loss of STAG2 is associated with the development of aneuploidy, this is not the case in Ewing sarcoma. To investigate whether STAG2 loss effects epigenetic regulation of gene expression in Ewing sarcoma, we developed isogenic Ewing sarcoma cell lines with STAG2 knockout. We found that Ewing sarcoma cells engineered for loss of STAG2 maintain an intact cohesion complex that alternately incorporates STAG1.
2021-05-14 | GSE116494 | GEO
Project description:Ewing sarcoma is an aggressive malignancy characterized by oncogenic rearrangements of the EWS gene with an ETS-family transcription factor, most commonly FLI. Recent comprehensive next-generation sequencing efforts have revealed few other highly recurrent mutations in this disease apart from loss-of-function mutations in STAG2 which occur in 15-20% of tumors. STAG2 is a member of the cohesin complex, which regulates sister chromatid alignment during mitosis and epigenetic regulation of gene expression. While some studies suggest that loss of STAG2 is associated with the development of aneuploidy, this is not the case in Ewing sarcoma. To investigate whether STAG2 loss effects epigenetic regulation of gene expression in Ewing sarcoma, we developed isogenic Ewing sarcoma cell lines with STAG2 knockout. We found that Ewing sarcoma cells engineered for loss of STAG2 maintain an intact cohesion complex that alternately incorporates STAG1.
2021-05-14 | GSE116492 | GEO
Project description:Ewing sarcoma is an aggressive malignancy characterized by oncogenic rearrangements of the EWS gene with an ETS-family transcription factor, most commonly FLI. Recent comprehensive next-generation sequencing efforts have revealed few other highly recurrent mutations in this disease apart from loss-of-function mutations in STAG2 which occur in 15-20% of tumors. STAG2 is a member of the cohesin complex, which regulates sister chromatid alignment during mitosis and epigenetic regulation of gene expression. While some studies suggest that loss of STAG2 is associated with the development of aneuploidy, this is not the case in Ewing sarcoma. To investigate whether STAG2 loss affects epigenetic regulation of gene expression in Ewing sarcoma, we developed isogenic Ewing sarcoma cell lines with STAG2 knockout. We found that Ewing sarcoma cells engineered for loss of STAG2 maintain an intact cohesion complex that alternately incorporates STAG1.
2021-05-14 | GSE165977 | GEO
Project description:Ewing sarcoma is an aggressive malignancy characterized by oncogenic rearrangements of the EWS gene with an ETS-family transcription factor, most commonly FLI. Recent comprehensive next-generation sequencing efforts have revealed few other highly recurrent mutations in this disease apart from loss-of-function mutations in STAG2 which occur in 15-20% of tumors. STAG2 is a member of the cohesin complex, which regulates sister chromatid alignment during mitosis and epigenetic regulation of gene expression. While some studies suggest that loss of STAG2 is associated with the development of aneuploidy, this is not the case in Ewing sarcoma. To investigate whether STAG2 loss effects epigenetic regulation of gene expression in Ewing sarcoma, we developed isogenic Ewing sarcoma cell lines with STAG2 knockout. We found that Ewing sarcoma cells engineered for loss of STAG2 maintain an intact cohesion complex that alternately incorporates STAG1.
2021-05-14 | GSE165783 | GEO
Project description:Cancers in the central nervous system resist therapies effective in other cancers, possibly due to the unique biochemistry of the human brain microenvironment comprised of cerebrospinal fluid (CSF). However, the impact of CSF on cancer cells and therapeutic efficacy is unknown. Here we examined the effect of human CSF on glioblastoma (GBM) tumours from 25 patients. We found that CSF induces tumour cell plasticity and resistance to standard GBM treatments (temozolomide and irradiation). We identified nuclear-protein-1 (NUPR1), a transcription factor hampering ferroptosis, as a mediator of therapeutic resistance in CSF. NUPR1 inhibition with a repurposed antipsychotic, trifluoperazine, enhanced the killing of GBM cells resistant to chemoradiation in CSF. The same chemo-effective doses of trifluoperazine were safe for human neurons and astrocytes derived from pluripotent stem cells. These findings reveal that chemoradiation efficacy decreases in human CSF and suggest that combining trifluoperazine with standard care may improve GBM patient survival.
2023-10-20 | GSE243501 | GEO
Project description:STAG2 is targeted by somatic aberrations in a subset (4%) of human PDAs. Transposon mediated disruption of STAG2 in a KRASG12D genetically engineered mouse model promotes the development of PDA and its progression to metastatic disease. There was a statistically significant loss of STAG2 protein expression in human tumor tissue (Wilcoxon-Rank test) with complete absence of STAG2 staining observed in 15 (4.3%) patients. In univariate Kaplan Meier analysis nearly complete STAG2 positive staining (> 95% of nuclei positive) was associated with a median survival benefit of 6.41 months (p = 0.031). The survival benefit of adjuvant chemotherapy was only seen in patients with a STAG2 staining of less than 95% (median survival benefit 7.65 months; p = 0.028). Multivariate Cox Regression analysis showed that STAG2 is an independent prognostic factor for survival in pancreatic cancer patients. Finally we show that RNAi mediated knockdown of STAG2 selectively sensitizes human PDA cell lines to platinum-based therapy. We used DNA content flow sorting to identify and purify tumor nuclei of PDA samples from 50 patients. The genome of each sorted sample was profiled by oligonucleotide comparative genomic hybridization (aCGH) and targeted resequencing of STAG2. Transposon insertions within STAG2 in a KRASG12D driven genetically engineered mouse (GEM) model of PDA were screened by RT-PCR. We then used a tissue microarray (TMA) to survey STAG2 protein expression levels in 344 human PDA tumor samples and adjacent tissues. Univariate Kaplan Meier analysis and multivariate Cox Regression analysis was used to assess the association of STAG2 expression relative to overall survival and responses to adjuvant therapy. Finally RNAi based assays with PDA cell lines were used to assess the potential therapeutic consequence of STAG2 expression in responses to 18 therapeutic agents.
2014-01-24 | E-GEOD-54328 | biostudies-arrayexpress
Project description:This study performed genomic sequencing on a rare phenotype of HPV-positive oropharyngeal squamous cell carcinoma which was resistant to standard of care platinum based chemoradiation treatment. Tissue was collected from archival FFPE when available from pretreatment and post treamtent samples from four patients and these were batch corrected to be compared to known HPV-positive tumors without recurrent disease
2024-02-23 | GSE256047 | GEO
Project description:Analysis of peripheral circulating mRNA expression levels in patients undergoing neoadjuvant chemoradiation for esophageal squamous cell carcinoma. The hypothesis test was that chemoradiation alters the circulating mRNA expression profiles and the profiling is predictive of pathological response. Results provide information on the response of circulating mRNAs to chemoradiation and identify novel biomarkers or targets in esophageal squamous cell carcinoma. Total RNA obtained from peripheral whole blood before and after neoadjuvant chemoradiation in patients with esophageal squamous cell carcinoma. 21 patients with 42 samples were analyzed. The expression profiles from pathological complete responders were compared to non-complete responders.
2014-01-01 | E-GEOD-43519 | biostudies-arrayexpress