5495 results for "*oma"

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• Sézary Syndrome Originates from Heavily Mutated Hematopoietic Progenitors

  The pathogenesis of cutaneous T cell lymphoma (CTCL) remains unclear. To study the malignant transformation of CTCL, we collected matched hematopoietic stem cell (HSC) extracts from bone marrow, CD4+CD26- malignant T cells, CD4+CD26+ normal T cells, and CD34+ HSCs from apheresis performed on 4 patients. To establish the baseline for calling true mutations without using hematopoietic cells, we also cultured bone marrow fibroblasts from each patient to use as normal controls. Whole exome sequencing (WES) was performed on all samples for somatic mutation calling. We identified >200 mutations in CD34+ HSCs derived from either bone marrow or apheresis. Previously reported key oncodrivers in Sezary Syndrome were identified in autologous HSCs and malignant peripheral cells, but not in progenitor (bone marrow HSCs) cells. Also, we identified specific mutations shared by autologous HSCs and malignant peripheral cells in every patient. WES data of bone marrow HSCs, apheresis HSCs, CD4+CD26- T cells, CD4+CD26+ T cells, and fibroblasts will be available through dbGaP.

  Study phs003158

• Metastatic Colorectal Adenocarcinoma Tumor Purity Assessment from Whole Exome Sequencing Data

  As molecular medicine wields greater and greater influence on cancer patient care, including therapeutic selection, it becomes increasingly important to understand the power and deficiencies of computational tools used in decision making processes. Here we use a set of unselected metastatic colorectal tumor samples in a head-to-head comparison between the calculation of stromal content by a board certified pathologist, versus that derived from whole exome sequencing and purity assessment by a variety of common computational methods. We find that in about 1/2 of the samples the computational methods each do a poor job of assessing the percent stromal contamination, and as a result, tumor variant allele frequencies (VAFs) are low or undetected, whereas analysis of organoids derived from the same tumors yielded much higher VAFs in keeping with their lower stromal content. The whole exome sequence of our samples is available via dbGaP, accession phs003059.v1.p1.

  Study phs003059

• National Eye Institute (NEI) Ocular Hypertension Treatment Study (OHTS)

  The Ocular Hypertension Treatment Study (OHTS) is an National Eye Institute-sponsored multi-center, randomized, prospective treatment trial designed to determine whether lowering intraocular pressure (IOP) in individuals with ocular hypertension delays or prevents the development of primary open angle glaucoma (POAG). A total of 1,636 individuals with ocular hypertension between 40 and 80 years old were enrolled in the study. In addition to ocular hypertension, subjects in the OHTS were required to have normal optic nerve appearance as determined by the OHTS Optic Disc Reading Center and normal and reliable visual field tests at the time of enrollment by the OHTS Visual Field Reading Center. OHTS subjects were randomly assigned to either an observational group which received close observation or a topical medication group which received medication as needed to achieve a 20% reduction in IOP from their baseline levels. Subjects then were examined at regular intervals for optic disc cupping or visual field defects. Other clinical measures were also obtained from OHTS subjects including central corneal thickness (CCT) and intraocular pressure. The primary outcome monitored for the OHTS was the development of glaucoma in one or both eyes as defined by reproducible visual field abnormality or reproducible optic disc deterioration attributed to POAG by the masked OHTS Endpoint Committee. The OHTS study design has been reported in detail (Gordon, 1999; PMID: 10326953). The OHTS confirmed that ocular hypertension is a risk factor for developing POAG and showed that lowering IOP reduced the risk for developing POAG (Kass, 2002; PMID: 12049574). The OHTS also demonstrated that thin CCT is a significant risk factor for the development of POAG (Gordon, 2002; PMID: 12049575). Blood samples were also collected from 1,077 OHTS participants for an ancillary genetics study. DNA was prepared from these samples and used in a genome-wide association scan (GWAS) designed to identify genetic factors that control the magnitude of quantitative features of glaucoma (baseline IOP, baseline cup-to-disc ratio, and CCT). Genotypes from the GWAS and these clinical data (IOP, cup-to-disc ratio, and CCT) have been provided to dbGaP.

  Study phs000240

• Genome-Wide Characterization of Pancreatic Adenocarcinoma Patients Using Next Generation Sequencing

  In this study, we whole genome sequenced tumor/normal pairs from three pancreatic adenocarcinoma patients to separately characterize each patient with respect to somatic alterations. For 2 patients for whom tumor RNA was available, we also performed RNA sequencing to evaluate gene expression changes. While additional sequencing is needed to improve our understanding of the disease, the information acquired from this study contributes to our knowledge base on pancreatic cancer and helps to establish a foundation for identifying and developing more efficacious treatments for patients.

  Study phs000550

• Genomic Analysis of Nucleic Acid Sequences from Pancreatic Cancer

  Our study aims to perform multi-omics analysis of pancreatic ductal adenocarcinoma. We performed dual single-cell RNA sequencing and whole genome sequencing on fresh tumor specimens and dual bulk RNA-sequencing and 16S amplicon sequencing on frozen tumor specimens to identify human and non-human nucleic acid sequences. Additionally, we identified microbial sequences and found that bacterial taxonomic profiles from the same sample strongly correlated across technologies.

  Study phs003035

• Cross-site Concordance Evaluation of Tumor DNA and RNA Sequencing Platforms of CIMAC-CIDC Network

  The Cancer Immune Monitoring and Analysis Centers (CIMACs) and the Cancer Immunologic Data Commons (CIDC)  has engaged in efforts to harmonize Whole-exome (WES) and RNA-sequencing (RNA-seq) data from three different experimental platforms (MD Anderson, NCI MoCha lab, and Broad Institute) and are using a series of developed pipelines to process the early trial samples. To evaluate the consistency of tumor WES and RNA-seq profiling platforms across different centers, the CIMACs-CIDC conducted a systematic harmonization study. DNA and RNA were centrally extracted from fresh frozen (FF) and formalin-fixed paraffin-embedded (FFPE) non-small cell lung carcinoma (NSCLC) tumors and distributed to three centers for WES and RNA-seq profiling

  Study phs002295

• Multi-Omic Investigation of Beckwith-Wiedemann Syndrome Wilms Tumor

  Wilms’ Tumor (WT), also known as nephroblastoma, is one of the most common malignant kidney tumors diagnosed in children. One of the most common WT predisposition syndromes is Beckwith-Wiedemann Syndrome (BWS, OMIM: 130650), which affects approximately 1/10,000 live births. In this study, we perform Whole Exome Sequencing (WES), DNA methylation array, and messenger RNA-Sequencing (mRNA-Seq), to examine the genomic, methylomic, and transcriptomic signature of BWS WT. We analyzed six tumor-normal paired samples, three BWS tumor only samples, and four non-BWS control samples to identify BWS WT drivers.

  Study phs002769

• Gut Microbiome and Types of Colorectal Polyps

  Colorectal cancer is a heterogeneous disease arising from at least two precursors-the conventional adenoma and the serrated polyp. This dataset was used to test the relationship of the gut microbiota to specific colorectal polyp types. We included samples from two independent study populations based at colonoscopy clinics: the Centers for Disease Control and Prevention (CDC) Study of In-home Tests for Colorectal Cancer (SIT), and the New York University (NYU) Human Microbiome and Colorectal Tumor study. Gut microbiota were assessed in 667 colonoscopy-screened adults by 16S rRNA gene sequencing of stool samples, of which 540 were included in our analysis. Participants were categorized as conventional adenoma cases, serrated polyp cases, or polyp-free controls. CA cases were further classified as proximal or distal and as non-advanced or advanced. Serrated polyp cases were further classified as hyperplastic polyp or sessile serrated adenoma. Our results show associations between gut microbiome composition and presence of conventional adenomas, including reduced diversity and alterations in taxon abundance.

  Study phs001381

• The Mutational Landscape of CTCL and Sezary Syndrome

  Sezary syndrome is a leukemic and aggressive form of cutaneous T-cell lymphoma (CTCL) resulting from the malignant transformation of skin-homing central memory CD4+ T cells. To identify new genetic alterations involved in Sezary syndrome and CTCL transformation we performed whole-exome sequencing of tumor-normal sample pairs from 26 Sezary syndrome and 16 CTCL patients. These analyses revealed a distinctive pattern of somatic copy number alterations in Sezary syndrome including highly prevalent recurrent chromosomal deletions involving the TP53, RB1, PTEN, DNMT3A, and CDKN1B tumor suppressor genes. Mutation analysis identified a broad spectrum of somatic mutations involving key genes involved in epigenetic regulation (TET2, CREBBP, MLL3, BRD9, SMARCA4 and CHD3) and signaling, including mutations in MAPK1, BRAF, CARD11 and PRKG1 driving increased MAPK, NFKB and NFAT activity upon T-cell receptor stimulation. Collectively, our findings provide new insights into the genetics of Sezary syndrome and CTCL and support the development of personalized therapies targeting key oncogenically activated signaling pathways for the treatment of these diseases.

  Study phs000994

• Medulloblastoma exome sequence analysis

  Medulloblastomas are the most common malignant brain tumors in children. Identifying and understanding the genetic events that drive these tumors is critical for the development of more effective diagnostic, prognostic and therapeutic strategies. Recently, our group and others described distinct molecular subtypes of medulloblastoma based on transcriptional and copy number profiles. Here, we utilized whole exome hybrid capture and Illumina sequencing to identify somatic mutations across the coding regions of 92 primary medulloblastoma/normal pairs. Overall, medulloblastomas exhibit low mutation rates consistent with other pediatric tumors, with a median of 0.35 non-silent mutations per megabase. We identified twelve genes mutated at statistically significant frequencies, including previously known mutated genes in medulloblastoma such as CTNNB1, PTCH1, MLL2, SMARCA4 and TP53. Recurrent somatic mutations were identified in an RNA helicase gene, DDX3X, often concurrent with CTNNB1 mutations, and in the nuclear co-repressor (N-CoR) complex genes GPS2, BCOR, and LDB1, to our knowledge novel findings in medulloblastoma and all cancer. We show that mutant DDX3X potentiates transactivation of a TCF promoter and enhances cell viability in combination with mutant but not wild type beta-catenin. Together, our study reveals the alteration of Wnt, Hedgehog, histone methyltransferase and now N-CoR pathways across medulloblastomas and nominates the RNA helicase DDX3X as a component of pathogenic beta-catenin signaling in medulloblastoma. "Reprinted from 'MEDULLOBLASTOMA EXOME SEQUENCING UNCOVERS SUBTYPE-SPECIFIC SOMATIC MUTATION', with permission from Nature"

  Study phs000504