4986 results for "*oma"

in 62.68 milliseconds.

• High Grade Serous Ovarian Carcinomas Originate in the Fallopian Tube

  High-grade serous ovarian carcinoma (HGSOC) is the most frequent type of ovarian cancer and has a poor outcome. It has been proposed that fallopian tube cancers may be precursors of HGSOC but evolutionary evidence for this hypothesis has been limited. To provide insights into the origins of HGSOC, we We performed whole-exome sequence and copy number analyses of laser-capture microdissected fallopian tube lesions (p53 signatures, serous tubal intraepithelial carcinomas (STICs), and fallopian tube carcinomas), ovarian cancers, and metastases from nine patients with HGSOC. The majority of tumor-specific sequence and structural alterations in ovarian cancers were present in STICs, including those affecting TP53, BRCA1, BRCA2 or PTEN genes. An eEvolutionary analyseis revealed that p53 signatures and STICs were are the precursors of ovarian carcinoma which in turn gave rise to metastatic lesionsand identify a. In one patient we identified a second STIC as a metastasis in the fallopian tube opposite from the affected ovary. These analyses revealed a window of seven years between the development of a STIC and the initiation of ovarian carcinomas, with development of metastases following rapidly thereafter. Our results provide insights into the etiology of ovarian cancer and have implications for the prevention, early detection and therapeutic intervention of this disease.

  Study EGAS00001002589

• Genome-wide identification of distinct miRNA-mRNA target regulation pairs in Non-Hodgkin lymphomas: a report from the ICGC MMML-Seq consortium

  We obtained miRNA profiles by miRnome sequencing from ICGC MMML-Seq patients diagnosed with Burkitt lymphoma, diffuse large B-cell lymphoma and follicular lymphoma and provide evidence of subtype-specific miRNA expression differences. We describe differentially expressed, mutated, edited and not previously annotated miRNAs. Addditionally, by performing argonaute-2 photoactivatable ribonucleoside-enhanced cross-linking and immunoprecipitation (PAR-CLIP) experiments, we obtained a set of biochemically-validated miRNA binding sites and identified miRNA-mRNA interaction pairs with a negative correlation in patient RNASeq data.

  Study EGAS00001001394

• Gut microbiome modulates response to anti PD1 immunotherapy in metastatic melanoma patients

  There is a growing appreciation of the role of the microbiome in cancer, and evidence in pre-clinical models that the gut microbiome may modulate responses to immune checkpoint blockade though this has not been well-characterized in patients. We analyzed the oral (n=86)and gut (n=43) 16S microbiome in melanoma patients on PD-1 blockade. Significant differences were noted in the diversity and composition of the gut microbiome between responders and non-responders in patients with a fecal microbiome sample, with significantly higher alpha diversity and relative abundance of Ruminococcaceae bacteria) in R. Metagenomic studies (n=25) revealed functional differences in gut bacteria in R including enrichment of anabolic pathways. Immune profiling demonstrated enhanced systemic and anti-tumor immunity in patients with a favorable gut microbiome as well as in germ-free mice receiving fecal transplant from responding patients. Together, these data have important implications for treatment with immune checkpoint blockade in cancer. The fastq files associated with this dataset are stored at ENA under the following accession numbers: PRJEB22894 (Fecal 16S), PRJEB22874 (Oral 16S), PRJEB22895 (Murine 16S), PRJEB22893 (Fecal WGS).

  Study EGAS00001002698

• Xenograft_Sequencing

  Sequencing of mouse/human carcinoma xenograft samples.

  Study EGAS00001000140

• Osteosarcoma_Whole_Genome

  We propose to definitively characterise the somatic genetics of Osteosarcoma cancer through generation of comprehensive catalogues of somatic mutations by high coverage genome sequencing.

  Study EGAS00001000147

• Targeted resequencing of ribosomal proteins in multiple myeloma patient samples.

  We studied 38 multiple myeloma samples to discover mutations in ribosomal proteins. To this end, we ran a specifically designed targeted resequencing study to resequence the coding regions of all ribosomal proteins.

  Study EGAS00001002405

• Colorectal advanced adenomas NKI-AvL TGO COCOS series

  Colorectal cancer (CRC) develops from normal epithelium, through a benign precursor lesion called adenoma, by accumulation of genetic alterations affecting oncogenes and tumour suppressor genes. About 5% of colorectal adenomas are estimated to progress to CRC. However, it is important to identify which adenomas actually carry a high-risk of progression, because these serve as intermediate endpoints for e.g. screening programs. In clinical practice, adenomas with a size of ≥10 mm, villous component and/or high-grade dysplasia, called advanced adenomas, are considered high-risk, although solid evidence for this classification is lacking. Specific DNA copy number changes are associated with adenoma-to-carcinoma progression.For this tissue dataset, we applied low-pass whole genome sequencing to 96 advanced adenomas. Advanced adenomas were classified as lesions with low-risk or high-risk of progression, according to the presence of specific DNA copy number changes (Carvalho et al, CancerPrevRes, 2018).

  Study EGAS00001002952

• RNAseq___Discovery_of_resistance_mechanisms_to_the_BRAF_inhibitor_vemurafenib_in_metastatic_BRAF_mutant_melanoma

  We propose to biopsy 20 consented BRAF mutant melanoma patients at Addenbrooke's Hospital pre-treatment with vemurafenib and also upon the development of resistant disease, with the aim of using exome sequence and SNP6 data to identify novel sequence variants and copy number alterations that can be used to validate observed resistance mechanisms in our cell line models and also to use these models to inform as to likely candidate small molecule inhibitors to overcome resistance and that could be tested in the clinical trial setting.

  Study EGAS00001000813

• The evolutionary history of human colitis-associated colorectal cancer

  Inflammatory bowel disease confers an increased lifetime risk of developing colorectal cancer (CRC), and colitis-associated CRC (CA-CRC) is molecularly distinct from sporadic CRC (S-CRC). Here we have dissected the evolutionary history of CA-CRC using multi-region sequencing. Exome sequencing was performed on fresh-frozen multiple regions of carcinoma, adjacent non-cancerous mucosa and blood from 12 CA-CRC patients (n=55 exomes), and key variants were validated with orthogonal methods. Genome-wide copy number profiling was performed using SNP arrays and low-pass whole genome sequencing on archival non-dysplastic mucosa (n=9), low-grade dysplasia (LGD, n=30), high-grade dysplasia (HGD, n=13), mixed LGD/HGD (n=7) and CA-CRC (n=19). Phylogenetic trees were reconstructed, and evolutionary analysis used to reveal the temporal sequence of events leading to CA-CRC. 10/12 tumors were microsatellite stable with a median mutation burden of 3.0 single nucleotide alterations (SNAs) per Mb, around 20% higher than S-CRC (2.5 SNAs/Mb), and consistent with elevated aging-associated mutational processes. Non-dysplastic mucosa had considerable mutation burden (median 47 SNAs), including mutations shared with the neighboring CA-CRC, indicating a pre-cancer mutational field. CA-CRCs were often near-triploid (42%) or near-tetraploid (21%) and phylogenetic analysis revealed that copy number alterations (CNAs) began to accrue in non-dysplastic bowel, but the LGD/HGD transition often involved a punctuated catastrophic CNA increase.

  Study EGAS00001003028

• Exome-wide analysis identifies three low-frequency missense variants associated with pancreatic cancer risk in Chinese populations

  Germline coding variants have not been systematically investigated for pancreatic ductal adenocarcinoma (PDAC). Here, we report an exome-wide investigation using the Illumina Human Exome Beadchip with 943 PDAC cases and 3,908 controls in the Chinese population, followed by two independent replicate samples including 2,142 cases and 4,697 controls. We identify three low-frequency missense variants associated with the PDAC risk: rs34309238 in PKN1 (OR = 1.77, 95% CI: 1.48-2.12, P = 5.35 X 10-10), rs2242241 in DOK2 (OR = 1.85, 95% CI: 1.50-2.27, P = 4.34 X 10-9) and rs183117027 in APOB (OR = 2.34, 95% CI: 1.72-3.16, P = 4.21 X 10-8).

  Study EGAS00001003040

• Conjunctival fibrosis and the innate barriers to Chlamydia trachomatis intracellular infection: a genome wide association study

  This data comes from a genome-wide association study in 1090 cases of scarring trachoma and 1531 controls from a non-selected multi-ethnic sampling of The Gambia. The data constitutes hard base calls at 1457295 features from the HumanOmni2.5-8 (Omni2.5) BeadChip. Three genotype-calling algorithms were used : Illuminus (Bioinformatics 2007, 23:2741–6), GenCall (Patent US7035740, 2006) and GenoSNP (Bioinformatics 2008, 24:2209–14). Data from each calling algorithm was filtered to retain only SNPs with a call rate ≥ 0.98. To obtain a merged set of SNPs, all genotypes that matched across call-sets were retained, whilst those that mismatched between call-sets were set to missing. Genotypes that were present in one call set and missing in others were also retained. The merged SNP set contained 1467876 SNPs, which were filtered for call rate ≥ 0.99 and Hardy-Weinberg equilibrium P value < 5 x 10-8. The case and control groups were approximately equivalent with respect to gender and ethnicity. 70% of cases and 63% of controls were female. Self-described ethnic composition of the cases was 29% Jola, 27% Mandinka, 21% Wolof, 10% Fula and 13% other/no data. In controls the composition was 25% Jola, 24% Mandinka, 21% Wolof, 8% Fula and 22% other/no data. Median age was 49 (range 32-60) in cases and 37 (range 12-52) in controls (t = -3.6019, P = 0.0003). This data set has substantial levels of population structure, which reflects extensive networks of pairwise kinship between participants. First pass tests of association in EMMAX (Nat Genet 2010, 42:348–54) led to genome-wide deflation of the test statistics (λ = 0.982 SE = 1.74e-05) that could be directly attributed to the differing age and gender distributions between cases and controls. Modelling the phenotype to adjust for age and gender successfully controlled for this and no genome-wide deviation from the null was subsequently observed (λ = 1.001, SE = 8.7 x 10-7). Neither principal components analysis (PCA) nor tests of proportional identity by state (IBS) variance in PLINK identified significant levels of within or between group genetic variance. The phenotypes submitted in the phenotypes file include both uncorrected (case/control status) and corrected (age and gender corrected case/control status) phenotypes, as well as age and self-described ethnicity.

  Study EGAS00001001516

• Genetic landscape of relapsed DLBCL

  Diffuse large B-cell lymphoma is a heterogenous malignancy that can arise de novo or can result from histologic transformation from indolent lymphomas. Considerable sequencing effort has been placed on determining the mutations that are common at the time of diagnosis in DLBCL but little is known about the nature of relapsed disease. We have sequenced tumour and matched normal exomes of 38 rrDLBCL patients including 25 de novo DLBCLs and 13 transformed lymphomas to identify somatic mutations and copy number alterations associated with relapse.

  Study EGAS00001001553

• Enhanced detection of circulating tumor DNA by fragment size analysis

  Existing methods to improve detection of circulating tumor DNA (ctDNA) have focused on sensitivity for detecting genomic alterations but have rarely considered the biological properties of plasma cell-free DNA (cfDNA). We hypothesized that differences in fragment lengths of circulating DNA could be exploited to enhance sensitivity for detecting the presence of ctDNA and for non-invasive genomic analysis of cancer. We surveyed ctDNA fragment sizes in 344 plasma samples from 200 cancer patients using low-pass whole-genome sequencing (0.4×). To establish the size distribution of mutant ctDNA, tumor-guided personalized deep sequencing was performed in 19 patients. We detected enrichment of ctDNA in fragment sizes between 90–150 bp, and developed methods for in vitro and in silico size selection of these fragments. Selecting fragments between 90–150 bp improved detection of tumor DNA, with more than 2-fold median enrichment in >95% of cases, and more than 4-fold enrichment in > 10% of cases. Analysis of size-selected cfDNA identified clinically actionable mutations and copy number alterations that were otherwise not detected. Identification of plasma samples from patients with advanced cancer was improved by predictive models integrating fragment length and copy number analysis of cfDNA, with AUC> 0.99 compared to AUC < 0.80 without fragmentation features. Increased identification of cfDNA from patients with glioma, renal, and pancreatic cancer was achieved with AUC > 0.91, compared to AUC < 0.5 without fragmentation features. Fragment size analysis and selective sequencing of specific fragment sizes can boost ctDNA detection. This could reduce the required depth of cfDNA sequencing for clinical applications, earlier diagnosis and study of tumor biology.

  Study EGAS00001003258

• Chordoma_Extension__known_cancer_genes_

  Extension analysis to pursue candidate genes of interest in chordoma

  Study EGAS00001000895

• H014: HES5 mediates NOTCH signaling by interaction with AKT to drive liver carcinogenesis

  Notch signaling plays a pivotal role in liver development and aberrant Notch signaling may lead to hepatocellular (HCC) or cholangiocellular carcinoma (CCA) development. Using whole exome sequencing of 54 human HCC samples, we discovered 19 somatic missense mutations in 15 different Notch pathway genes affecting 24.6% (14 of 57) of patients. Prediction of functional impact of these Notch pathway mutations revealed HES5-R31G to have high relevance. We found HES5 to be strongly activated by Notch signaling. In vitro, HES5 reduced cell migration and clonogenicity and in vivo, HES5 inhibited MYC-dependent liver tumor formation. But together with AKT, HES5 increased liver tumor formation in a mouse model. HES5 directly binds to AKT and AKT expression leads to increase HES5 protein levels. Furthermore, HES5 exhibits a negative feed-back loop by inhibiting NOTCH1 and HES1 gene expression. In contrast, HES5-R31G appears to be non-functional possibly by loss of nuclear translocation

  Study EGAS00001003329

• Whole genome and RNA sequencing of paediatric glioblastoma in the ICGC PedBrain project

  Paediatric glioblastoma (pedGBM) is characterised by substantial intertumoural heterogeneity. In order to identify the genetic lesions underlying tumourigenesis, we analysed whole genomes and transcriptomes of pedGBMs and in vitro model systems by next generation sequencing. Novel fusions of the receptor tyrosine kinase MET lead us to investigate targeted therapy using MET inhibitors. This study is part of the International Cancer Genome Consortium PedBrain Tumor Project (ICGC PedBrain, http://www.pedbraintumor.org/).

  Study EGAS00001001139

• Whole genome sequencing of Ewings Sarcoma

  Sarcomas are cancers of the bone and soft tissue often defined by their gene fusions. However, the timing, context, and processes by which these pathogenic fusions arise are unknown. We explored this in Ewing sarcoma, a cancer driven by EWSR1-ETS fusions, with very few cooperating mutations. Combining whole-genome sequencing with enhanced informatics, we found that the EWSR1-ETS fusion arose from striking rearrangement clusters in 42% of cases (52/124). Notably, these were organized in loops that universally contained the fusion at their center, while also weaving up to 18 genes together with it. We found the same pattern of rearrangements in three additional types of sarcoma. From these data, we define a new signature for sarcoma fusions that precedes other somatic changes, in the earliest replicating DNA of the genome. This dramatic, sudden process impinges on many genes – generating multiple coding changes that profoundly affect the transcriptome, with the disease-defining gene fusion at its core. These rearrangement loops emerge in an early ES clone from which both the primary tumor and the lethal relapse emerged, and then evolved in parallel until clinically detected.

  Study EGAS00001003385

• The genomic landscape of follicular and diffuse large B-cell lymphoma

  As part of the ICGC, the ICGC MMML-Seq project performed whole genome sequencing and RNA sequencing of follicular and diffuse large B-cell lymphoma. Follicular and diffuse large B-cell lymphomas are the most common B-cell lymphomas in adulthood. Analyses were performed in concordance with the guidelines of the ICGC. The results define the genomic landscape of structural variants, somatic single nucleotide variants and mutational signatures in these lymphomas

  Study EGAS00001002199

• Genetic Landscape of Esophageal Squamous Cell Carcinoma Defined by Exome Sequencing on Chinese Patient Cohort and Cell Lines

  Esophageal Squamous Cell Carcinoma (ESCC) is one of the deadliest cancers worldwide. To define the genetic landscape of ESCC, whole exome sequencing was performed on 113 pairs of tumor and normal DNA samples collected from Chinese individuals with treatment-naive primary ESCC, along with 8 cell lines, including 7 from KYSE series ESCC cell lines and one immortalized esophageal squamous epithelial cell line Het-1A.

  Study EGAS00001000932

• Evolution of GBM through therapy

  Primary glioblastoma (GBM) tumours recur following treatment. This is likely due to intratumour heterogeneity (ITH), which reduces the effectiveness of cancer therapies by enabling therapy-driven tumour evolution: Darwinian selection of genotypically and/or phenotypically distinct cells (subclones) that resist treatment to seed regrowth of an even less treatable recurrence. To investigate this we sequenced a pilot cohort of nine paired primary and locally recurrent GBM tumours, alongside matched blood samples, in order to begin characterising therapy resistant cells and thereby infer the mechanisms by which they evaded treatment. These data were included in the first data release from the Glioma Longitudinal AnalySiS (GLASS) consortium.

  Study EGAS00001003546

• Revealing active mutational processes in tumours using DigiPico/MutLX at unprecedented accuracy

  Active mutational processes in a tumor result in genetic micro-heterogeneity that can determine the tumor’s evolutionary trajectory. Identification of these processes by studying micro-heterogeneity can unveil novel aspects of tumor evolution with potential therapeutic implications. Such studies, however, are inherently problematic because of the discovery of excessive false positive mutations. Here we report the optimization and validation of a robust whole genome sequencing and analysis pipeline (DigiPico/MutLX) that virtually eliminates false positive results. Using our method, we identified, for the first time, a sub-clonal local hyper-mutation (kataegis) event in a recurrent ovarian carcinoma, which was unidentifiable from the bulk WGS data of the same tumor. Overall, we propose DigiPico/MutLX method as a powerful framework for the reliable study of genetic micro-heterogeneity in tumor and normal tissues.

  Study EGAS00001003555

• Single cell transcriptomic and genomic profiling of carcinogenesis in patients with familial adenomatous polyposis

  Familial Adenomatous Polyposis (FAP) is characterized by hundreds to thousands of adenocarcinomas at different evolutional stages in the colon and rectum. Much effort has been made to illuminate the key genomic alterations that facilitate the transition from adenoma to carcinoma. However, the strong heterogeneity of the tumors may hamper these efforts. Here, by sequencing matched adjacent normal tissues, adenomas at different stages and carcinomas from the same patient, we precisely traced the process of colorectal carcinogenesis. Our study offers an accurate genomic landscape during the initiation and progression of carcinogenesis, especially for the transition between adenomas and carcinomas.

  Study EGAS00001003598

• Analysis of copy number variation landscape of glioma by shallow coverage whole genome sequencing

  We reported shallow coverage whole genome sequencing (WGS) is an economic method for identification of whole genome somatic copy number variation (SCNV). Combining with a Taqman low density array (TLDA) designed for molecular subtyping of glioma, it enabled classification of glioma into biological entities with different cellular origin and genomic alterations. Further, we also showed shallow-coverage WGS enabled systematic identification of clonal and subclonal SCNV in glioma genomes and the burden and pattern of SCNV can serve as an objective marker of tumor progression and predict risk and relapse.

  Study EGAS00001003690

• Infant Glioma Molecular Subtype

  Infant gliomas have completely different clinical behavior than gliomas in children and adults. Low-grade tumors are more aggressive with a higher mortality rate, while high-grade tumors are more benign. However, we have little understanding of their biology and so cannot explain this behavior and what constitutes optimal clinical management. To solve this enigma, we performed a comprehensive genetic analysis of the largest cohort to date of infantile gliomas. We uncovered several important findings which dramatically change the management of these cancers. Infant hemispheric gliomas harbor unique alterations in ROS, ALK, MET and other genes found in adult carcinomas. Unlike in adults, they are typically the only alteration present and some of these tumors regress from high- to low-grade partially explaining their favorable clinical outcome. Midline gliomas harbor RAS/MAPK pathway mutations, progress rapidly, and do not respond to current chemoradiation approaches, partially explaining their poorer outcome. These data suggest that infant gliomas require different therapeutic approaches including early use of targeted therapies.

  Study EGAS00001003714

• Integrated genomic, transcriptional and epigenomic analyses in germinal center-cell lymphomas link the mutation landscape with differential DNA methylation in Burkitt lymphoma

  Biologically and clinically diverse B-cell neoplasms, including Burkitt, follicular and diffuse large B-cell lymphoma, show features of germinal center (GC) B-cells. Here we present a comprehensive analysis of the epigenetic landscape of GC-B-cell lymphomas using whole genome bisulfite sequencing paired with genome and transcriptome sequencing from 29 primary tumor samples and four normal GC-B-cell samples. All lymphomas studied showed extensive genome-wide methylation losses as well as intragenic regions where DNA methylation levels were strongly correlated with expression of associated genes. Pathway analysis revealed that these intragenic regions were enriched in signaling networks differentially activated in Burkitt and follicular lymphomas and affected regulatory mechanisms deregulated by recurrent mutations in a large fraction of Burkitt lymphomas (including the ID3/TCF3 complex, the SWI/SNF remodeling complex and the inhibitory GI signaling pathway). Taken together, these results provide a global picture of Burkitt lymphoma pathomechanism and demonstrate a tight connection between epigenetic regulation and other levels of regulatory control in these tumors.

  Study EGAS00001001067