4772 results for "*oma"

in 33.67 milliseconds.

• Balanced_Brain_Tumour_Whole_Genome_Sequencing

  We propose to definitively characterise the somatic genetics of a number of pediatric malignant tumours including ependymoma, high grade glioma and central nervous system primitive neurectodermal tumours through generation of comprehensive catalogues of somatic mutations by high coverage genome sequencing.

  Study EGAS00001000360

• Small molecule inhibitors of LOXL synergize with 5-AZA to restore erythropoiesis in myeloid neoplasms

  Objectives: Bone marrow (BM) stroma and microenvironmental factors in the BM milieu of myeloid neoplasms are increasingly being recognized as novel perspective therapeutic targets. Lysyl oxidases (LOX/LOXL) are crucial enzymes that cross-link collagen and contribute to the deposition of aberrant stiff extracellular matrix (ECM) in the BM of patients with myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN). Here, we studied whether inhibition of LOX/LOXL enzymes produced by BM-derived MSCs favors the differentiation of MDS/MPN hematopoietic stem cell and progenitor cells (HPSCs) and enhances the effects of 5-azacytidine (5-AZA). Methods: Primary co-cultures of MSCs and HPSCs were established from n=31 MDS/MPN patients and treated with the pan-LOX/LOXL inhibitor PXS-5505, 5-AZA or the combination of both for 4 days. At the end of co-culture, HSPC differentiation was assessed by CFU assays and flow cytometry. In some of the experiments, MSCs monolayers were pre-treated or not with PXS-5505 for 6 days and decellularized using 20 mM ammonia. Subsequently, autologous HSPCs were cultured on ECM matrices in the presence of 5-AZA or PXS-5505 + 5-AZA combination with or without inhibitors of integrin signaling such as blebbistatin, Y-27632 and αvβ3-integrin blocking antibodies. Patient-derived xenografts (PDX) were established in NSG mice based on intrafemoral co-injection of HSPCs and autologous MSCs. PDX were treated with 3 cycles of 5-AZA (75 mg/m2), PXS-5505 (30 mg/kg on alternate days for the duration of 5-AZA treatment) or combination of both. Results: MSCs of MDS and MPN patients displayed significant overexpression of LOX/LOXL transcripts as compared to healthy age-matched controls. Remarkably, LOX/LOXL inhibition in MSCs/HSPCs co-cultures increased erythroid differentiation of patient HSPCs that had suboptimal or no response to 5-AZA alone. From a total of n=31 advanced stage MDS/MPN patients, n=11 (35.5%) responded to the combination treatment, which was evidenced by a significant increase of CD235a+CD45- erythroid cell production compared to 5-AZA/PXS/untreated arms (p<0.05). Of note, combination treatment with 5-AZA + PXS-5505 facilitated differentiation of CD235+ erythroid progenitors from HSPCs sub-clones with low mutational VAFs. The presence of MSCs was necessary for the effects of the combination treatment and required direct cell contacts between MSCs and HSPCs. Moreover, PXS-5505-mediated alterations of the ECM composition alone were sufficient to induce erythroid differentiation. Inhibition of integrin-mediated signaling using blebbistatin, Y-27632 and αvβ3-integrin antibodies completely abrogated the effects of PXS-5505 induced erythroid differentiation. In vivo, the combination of PXS-5505 + 5-AZA favored erythroid differentiation of HSPCs and confirmed the in-vitro results. The combination treatment of 5-AZA + PXS-5505 induced the greatest reduction of disease burden as assessed by decrease of spleen indexes, total engraftment rates, BM fibrosis and mutational VAF profiles. Conclusions: The combination of 5-AZA + LOX/LOXL inhibitor PXS-5505 in MDS and MPN synergistically restores erythropoietic differentiation of primary HSPCs. The effect is dependent of contact interaction between HSPCs and niche components, such as MSCs and MSCs-derived ECM. Our data propose a strong rationale for a BM niche targeted combination treatment with 5-AZA + PXS-5505 in transfusion dependent MDS and MPN, which will be assessed in forthcoming clinical trials.

  Study EGAS00001006174

• Integrated genomic analyses identify ARID1A and ARID1B alterations in the childhood cancer neuroblastoma

  Neuroblastomas are tumors of peripheral sympathetic neurons and are the most common solid tumor in children. To determine the genetic basis for neuroblastoma we performed whole-genome sequencing (6 cases), exome sequencing (16 cases), genome-wide rearrangement analyses (32 cases), and targeted analyses of specific genomic loci (40 cases) using massively parallel sequencing. On average each tumor had 19 somatic alterations in coding genes (range, 3-70). Among genes not previously known to be involved in neuroblastoma, chromosomal deletions and sequence alterations of chromatin remodeling genes, ARID1A and ARID1B, were identified in 8 of 71 tumors (11%) and were associated with early treatment failure and decreased survival. Using tumor-specific structural alterations, we developed an approach to identify rearranged DNA fragments in sera, providing personalized biomarkers for minimal residual disease detection and monitoring. These results highlight dysregulation of chromatin remodeling in pediatric tumorigenesis and provide new approaches for the management of neuroblastoma patients.Data Provider: Johns Hopkins Sidney Kimmel Comprehensive Cancer Center (SKCCC)

  Study EGAS00001000369

• Genome-wide mutation analysis of germinal-center B-cell derived lymphomas within the ICGC MMML-Seq Consortium

  Germinal-center B-cell derived lymphomas (GCB-lymphomas) are the most common B-cell lymphomas in children and adults, with Burkitt Lymphomas (BL) predominating in childhood and follicular lymphoma (FL) and diffuse large B-cell lymphomas (DLBCL) predominating in older age groups. The cell-of-origin in all these lymphomas is supposed to be a germinal center B-cell and transformation of FL in DLBCL or intermediate DLBCL/BL (intL) can occur. In the framework of the German ICGC MMML-Seq we are currently exploring sequencing data of GCB-lymphomas and paired normal controls as well as normal B-cell subsets separated by FACS. This includes whole genome, transcriptome, miRNAome and whole methylome datasets.

  Study EGAS00001000394

• Chordoma_Sequencing_Project_RNAseq

  This is a continuation of the Chordoma Sequencing Project. All cancers arise due to somatically acquired abnormalities in DNA sequence. Systematic sequencing of cancer genomes allows acquisition of complete catalogues of all classes of somatic mutation present in cancer. These mutation catalogues will allow identification of the somatically mutated cancer genes that are operative and characterise patterns of somatic mutation that may reflect previous exogenous and endogenous mutagenic exposures. In this application, we aim to perform whole genome sequencing on 10 chordoma matched genome pairs. RNA Sequencing/Methylation and SNP6 and an additional sequencing of three cancer cell lines will be added to this work.

  Study EGAS00001000410

• Whole genome and transcriptome analysis of a sporadic and recurring parathyroid carcinoma

  Parathyroid carcinoma is an extremely rare endocrine malignancy with an estimated incidence of less than 1 per million population. Excessive secretion of parathyroid hormone, extremely high serum calcium level and the deleterious effects of hypercalcemia are the clinical manifestations of the disease. Up to 60% of patients develop multiple disease recurrences and although long-term survival is possible with palliative surgery, permanent remission is rarely achieved. Molecular drivers of sporadic parathyroid carcinoma have remained largely unknown. Previous studies, mostly based on familial cases of the disease, suggested a potential role for the tumor suppressor MEN1 and proto-oncogene RET in benign parathyroid tumorigenesis while the tumor suppressor HRPT2 and proto-oncogene CCND1 may also act as drivers in parathyroid cancer. Here, we report the complete genomic analysis of a sporadic and recurring parathyroid carcinoma. Mutational landscapes of the primary and recurrent tumor specimens were analyzed using high throughput sequencing technologies. Such molecular profiling allowed for identification of somatic mutations never previously identified in this malignancy. These included single nucleotide point mutations in well characterized cancer genes such as mTOR, MLL2, CDKN2C and PIK3CA. Comparison of acquired mutations in patient-matched primary and recurrent tumors revealed loss of PIK3CA activating mutation during the evolution of the tumor from the primary to the recurrence. Structural variations leading to gene fusions and regions of copy loss and gain were identified at a single-base resolution. Loss of short arm of chromosome 1 along with somatic mis-sense and truncating mutations in CDKN2C and THRAP3, respectively, provide new evidence for the potential role of these genes as tumor suppressors in parathyroid cancer. The key somatic mutations indentified in this study can serve as novel diagnostic markers as well as therapeutic targets.

  Study EGAS00001000484

• Hypermutation of the inactive X chromosome is a frequent event in cancer

  Mutation is a fundamental process in tumorigenesis. However the degree to which the rate of somatic mutation varies across the human genome and the mechanistic basis underlying this variation remain to be fully elucidated. As part of the ICGC PedBrain and Malignant Lymphoma (MMML-Seq) consortium we performed a cross-cancer comparison of whole genomes comprising a diverse set of childhood and adult tumors including both solid and hematopoietic malignancies. In addition we performed whole genome sequencing of clonally expanded hematopoietic stem/progenitor cells (HSPCs) from healthy individuals to compare somatic mutation rates.

  Study EGAS00001000565

• Osteosarcoma_X10

  This is a continuation of the osteosarcoma work we have undertaken.

  Study EGAS00001002167

• RB1 Gene Inactivation by Chromothripsis in Human Retinoblastoma

  Retinoblastoma is a rare childhood cancer of the developing retina. Most retinoblastomas initiate with biallelic inactivation of the RB1 gene through diverse mechanisms including point mutations, nucleotide insertions, deletions, loss of heterozygosity and promoter hypermethylation. Recently, a novel mechanism of retinoblastoma initiation was proposed. Gallie and colleagues discovered that a small proportion of retinoblastomas lack RB1 mutations and had MYCN amplification [1]. In this study, we identified recurrent chromosomal, regional and focal genomic lesions in 94 primary retinoblastomas with their matched normal DNA using SNP 6.0 chips. We also analyzed the RB1 gene mutations and compared the mechanism of RB1 inactivation to the recurrent copy number variations in the retinoblastoma genome. In addition to the previously described focal amplification of MYCN and deletions in RB1 and BCOR, we also identified recurrent focal amplification of OTX2, a transcription factor required for retinal photoreceptor development. We identified 10 retinoblastomas in our cohort that lacked RB1 point mutations or indels. We performed whole genome sequencing on those 10 tumors and their corresponding germline DNA. In one of the tumors, the RB1 gene was unaltered, the MYCN gene was amplified and RB1 protein was expressed in the nuclei of the tumor cells. In addition, several tumors had complex patterns of structural variations and we identified 3 tumors with chromothripsis at the RB1 locus. This is the first report of chromothripsis as a mechanism for RB1 gene inactivation in cancer.

  Study EGAS00001000598

• Whole-Genome sequencing of hepatocellular carcinomas

  The French ICGC project on liver tumors is coordinated by Pr Jessica Zucman-Rossi and funded by Inca (French Institute for Cancer). The aim of the present project is to identify the catalog of somatic and germline mutations in liver tumors using whole genome and whole exome sequencing together with CGH-SNP, methylome and transcriptomic profiling. For this purpose, a series of 500 liver tumors are collected through the French National Liver Collection and these samples will be analyzed using the different omics technologies. The data will be deposited in the ICGC and EGA database to be publically available for the scientific community. Hepatocellular carcinoma (HCC) accounts for more than 90% of liver cancers, and is a major health problem. It is the 3rd cause of cancer-related mortality. Advances in genomic analyses have formed a comprehensive understanding of different underlying pathobiological layers resulting in hepatocarcinogenesis. Thus, the development of next-generation sequencing technologies has made it possible to generate more comprehensive catalogues of somatic alteration events (single nucleotide substitutions, structural variations, and epigenetic changes) in liver cancer genome than ever before. The dataset will include 50 whole genome sequencing tumor/germline pairs, of which 6 are deposited in February 2014.

  Study EGAS00001000706

• ICGC Oesophageal adenocarcinoma - tumour samples

  The oesophageal project will focus on adenocarcinoma which is increasing in incidence in the UK and other developed countries and has a very poor outcome. The primary aims of this project are to deeply sequence tumour and normal genomic DNA (including the precursor condition Barrett’s oesophagus when material is available) to provide a comprehensive catalogue of somatic mutations. This will be achieved through a UK-wide network of hospitals involved in a research collaboration called the OCCAMS consortium. The goal of this project is to use high quality clinical material with accurately annotated clinic-pathological, treatment and outcome data.

  Study EGAS00001000725

• Genomic catastrophes frequently arise in esophageal adenocarcinoma and drive tumorigenesis.

  Oesophageal adenocarcinoma (EAC) incidence is rapidly increasing in Western countries. A better understanding of EAC underpins efforts to improve early detection and treatment outcomes. While large EAC exome sequencing efforts to date have found recurrent loss-of-function mutations, oncogenic driving events have been underrepresented. Here we use a combination of whole-genome sequencing (WGS) and single-nucleotide polymorphism-array profiling to show that genomic catastrophes are frequent in EAC, with almost a third (32%, n=40/123) undergoing chromothriptic events. WGS of 22 EAC cases show that catastrophes may lead to oncogene amplification through chromothripsis-derived double-minute chromosome formation (MYC and MDM2) or breakage-fusion-bridge (KRAS, MDM2 and RFC3). Telomere shortening is more prominent in EACs bearing localized complex rearrangements. Mutational signature analysis also confirms that extreme genomic instability in EAC can be driven by somatic BRCA2 mutations. These findings suggest that genomic catastrophes have a significant role in the malignant transformation of EAC.

  Study EGAS00001000750

• Whole_Exome_PC9_and_A375

  Drug resistant population of PC9(human non-small cell lung cancer) or A375 (human melanoma) cell lines were used for this study. By exome sequencing, we will analyse mutations of cells in drug tolerent state and after drug holiday.

  Study EGAS00001002493

• CMF_RNA_sequencing

  RNA sequencing will be undertaken to reconstruct rearrangements at level of transcription to determine pathogenomic genomic events in chondromyxoid fibroma

  Study EGAS00001000470

• Whole genome, whole exome, and targeted sequencing of high-grade meningioma tumor samples.

  High-grade meningiomas frequently recur and are associated with high rates of morbidity and mortality. To determine the factors that promote the development and evolution of these tumors, we analyzed the genomes of 274 high-grade meningiomas and compared this information with data from 456 low-grade meningiomas. High-grade meningiomas had a higher mutation burden than low-grade meningiomas but did not harbor any statistically significant mutated genes aside from NF2. High-grade meningiomas also possessed significantly elevated rates of chromosomal gains and losses, especially among tumors with monosomy 22. Meningiomas previously treated with adjuvant radiation had significantly more copy number alterations than radiation-induced or radiation-naïve meningiomas. Across serial recurrences, genomic disruption preceded the emergence of nearly all mutations, remained largely uniform across time, and when present in low-grade meningiomas, correlated with subsequent progression to a higher grade. In contrast to the largely stable copy number alterations, mutations were strikingly heterogeneous across tumor recurrences, likely due to extensive geographic heterogeneity in the primary tumor. While high-grade meningiomas harbored significantly fewer overtly targetable alterations than low-grade meningiomas, they contained numerous mutations that are predicted to be neoantigens, suggesting that immunologic targeting may be of therapeutic value.

  Study EGAS00001002294

• Chondromyxoid_fibroma

  Chondromxoid fibroma is a benign tumour of bone with unknown underlying pathogenesis. To determine pathognomic genomic event in chondromyxoid fibroma whole genome sequencing will be undertaken to reconstruct rearrangements and find underlying mutations.

  Study EGAS00001000533

• Deep_sequencing_of_melanoma_for_driver_mutations

  Deep sequencing of melanoma for driver mutations

  Study EGAS00001000857

• Uveal melanoma patient with germline MBD4 nonsense mutation

  There is currently no effective treatment for metastasised uveal melanoma (UM). Recently, it was reported that a UM patient was responsive to checkpoint inhibitor (CI) treatment, due to a high tumour mutation burden correlated with a germline loss-of-function MBD4 mutation. Here, we report on another UM patient who carried an MBD4 germline nonsense variant (p.Leu563Ter) and her tumour showed a 5-fold higher than average mutation burden. We confirmed the association between germline loss-of-function variant in MBD4 and CI response. The patient experienced stable disease (10 months) and survived two years with metastatic disease, which is twice as long as median survival. Additionally, the frequency of MBD4 loss-of-function variants in reported UM cohorts was >20 times higher than in an aggregated population genome database (P < 5x10-5), implying a potential role as UM predisposition gene. These findings provide a strong basis for the inclusion of MBD4 in screening of potential UM-prone families as well as stratification of immunotherapy.

  Study EGAS00001003362

• Spatio-temporal evolution of the primary glioblastoma genome

  Tumor recurrence following treatment is the major cause of mortality for glioblastoma multiforme (GBM) patients. Thus, insights on the evolutionary process at recurrence are critical for improved patient care. Here, we describe our genomic analyses of 38 GBM patients with the initial and recurrent tumor specimens for each individual. A substantial divergence in the landscape of driver alterations was associated with distant appearance of a recurrent tumor from the initial tumor, suggesting that the genomic profile of the initial tumor can mislead targeted therapies for the distally recurred tumor. In addition, in contrast to IDH1-mutated gliomas, IDH1-wild-type primary GBMs rarely developed hypermutation following temozolomide (TMZ) treatment, indicating low risk of TMZ-induced hypermutation for these patients under the standard regimen.

  Study EGAS00001001041

• Single-cell RNA-seq of immune cells sorted from human melanoma tumors

  Tumor immune cell compositions play a major role in response to immunotherapy but the heterogeneity and dynamics of immune infiltrates in human cancer lesions remain poorly characterized. Here we identify conserved intratumoral CD4 and CD8 T cell behaviors in scRNA-seq data from 25 melanoma patients. We discover a large population of CD8 T cells showing continuous progression from an early effector "transitional" into a dysfunctional T cell state. CD8 T cells that express a complete cytotoxic gene set are rare, and TCR sharing data suggest their independence from the transitional and dysfunctional cell states. Notably, we demonstrate that dysfunctional T cells are the major intratumoral proliferating immune cell compartment and that the intensity of the dysfunctional signature is associated with tumor-reactivity. Our data demonstrate that CD8 T cells previously defined as exhausted, are in fact a highly proliferating, clonal and dynamically differentiating cell population within the human tumor microenvironment.

  Study EGAS00001003363

• BAP1_sequence_of_uveal_melanoma_cell_lines

  Detection of BAP1 mutations in DNA from 3 uveal melanoma cell lines.

  Study EGAS00001001520

• Intra-tumor heterogeneity and clonal evolution patterns towards platinum-resistant high-grade serous ovarian cancer

  Although many high-grade serous ovarian carcinoma (HGSOC) patients are initially sensitive to the standard-of-care platinum-based therapy, intra-tumor heterogeneity may fuel selection towards platinum-resistant clones over subsequent lines of therapy. We performed whole-exome coupled to ultra-deep re-sequencing and copy number alteration (CNA) profiling on 31 matched diagnosis and relapse tumors from HGSOC patients treated with platinum. Genetic heterogeneity within tumor pairs varied extremely, with some recurrent tumors being identical and others completely different from the primary tumor. All primary tumors showed evidence of homologous recombination (HR)-deficiency, but none of them carried reactivating mutations in the HR pathway at relapse, also not when becoming resistant to subsequent lines of platinum. We did also not identify other mutations, CNAs or pathways that were enriched in platinum-resistant clones. However, a platinum score consisting of 13 CNAs correlated significantly with platinum-free interval (PFI) after first-line therapy in multiple cohorts of >450 primary HGSOCs. A relative increase of this score in the relapsed tumor correlated with a change in PFI during subsequent therapy. Clonal evolution under platinum therapy contributes to genetic heterogeneity within tumor pairs, implicating that genetic tests linked to targeted treatment options for recurrent HGSOC need to be performed on biopsies collected at relapse. Platinum resistance of an initially platinum-sensitive HR-deficient HGSOC at relapse is not caused by reactivation of the HR pathway, suggesting that these tumors are still responsive to PARP inhibitors, instead, several chromosomal aberrations contribute to a score predictive of disease outcome under platinum therapy, both in first and subsequent lines of platinum therapy.

  Study EGAS00001001244

• Tracking the genomic evolution of esophageal adenocarcinoma through neoadjuvant chemotherapy

  Esophageal adenocarcinomas (EACs) are associated with dismal prognosis. Deciphering the evolutionary histories of this disease may shed light on therapeutically tractable targets and reveal changing mutational processes during the disease course and following neoadjuvant chemotherapy (NAC). We exome sequenced 40 tumor regions from 8 patients with operable EACs both before and after platinum-containing NAC. This revealed the evolutionary genomic landscape of EACs with the presence of heterogeneous driver mutations, parallel evolution, early genome doubling events and an association between high intratumor heterogeneity and poor response to NAC. Multi-region sequencing demonstrated a significant reduction in T>G mutations within a CTT context when comparing early and late mutational processes and the presence of a platinum signature with enrichment of C>A mutations within a CpC context following NAC. EACs are characterized by the presence of amplifications containing targetable oncogenes present before and after chemotherapy that may provide a rationale for future therapeutic approaches.

  Study EGAS00001001254

• Independent development of lymphoid and histiocytic malignancies from a shared early precursor

  Recent reports have described lineage flexibility in patients with recurrent hematologic malignancies. We encountered a boy with T-lineage acute lymphoblastic leukemia, non-Langerhans cell histiocytosis and histiocytic sarcoma. All tumors showed identical T-cell receptor rearrangements, but SNP arrays and whole exome sequencing revealed unique aberrations in each tumor. From the genetic data we conclude that the tumors were derived from a precursor cell with lineage plasticity for both lymphoid and myeloid development. From this precursor cell, the tumors evolved with independent genetic progression in a non-linear manner.

  Study EGAS00001001353

• Exome Sequencing to Define the Landscape of Plasma Cells in Systemic Light chain Amyloidosis

  Systemic light chain amyloidosis (AL) is characterized by the deposition of immunoglobulin light chains as amyloid fibrils in different organs, where they form toxic protein aggregates. The underlying disease is a plasma cell disorder, but limited whole exome data are available. We report the findings of an exome sequencing study in AL to define a plasma cell signature and compare this to monoclonal gammopathy of undefined significance (MGUS) and myeloma (MM). Twenty-four samples from unselected newly diagnosed untreated AL patients were analysed. CD138+ cells were isolated from bone marrow cells using MACSorting (Miltenyi Biotech, Bisley, UK). Cells were lysed in RLT+ buffer and DNA/RNA extracted using the AllPrep kit (Qiagen, Manchester, UK). Peripheral blood was isolated from patients, white blood cells purified by Ficoll-Pacque and DNA extracted using the QIAamp DNA mini kit (Qiagen). There were a median of 47 acquired nonsynonymous variants (range 4-253) per patient. Thirty percent of patients yielded a mutation in a myeloma driver gene. These mutations were either clonal or sub-clonal. There was evidence of MAPK activation with NRAS mutations, NF-κB activation and DNA repair pathway alterations. Exome data were used to determine the cytogenetic groups of AL samples and identified hyperdiploidy in 33% of cases and t(11;14) in 33% of cases. All translocations were generated via class switch recombination and breakpoints on chromosome 11 fell into the expected regions. A novel translocation, unlikely to be driving disease progression was identified involving RCC1. Finally, further analysis of the APCS gene encoding for the SAP protein did not show any biased genotype in the AL population in comparison to the general population. We conclude that exome sequencing identifies a genetic make-up of AL that is similar to other plasma cell disorders such as MM and MGUS. This not only includes copy number abnormalities and translocations but also nonsynonymous mutations.

  Study EGAS00001001418