11762 results for "cancer rna-seq"

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• Structure and evolution of double minutes in diagnosis and relapse brain tumors

  Double minute chromosomes are extrachromosomal circular DNA fragments frequently found in brain tumors. To understand their evolution, we characterized the double minutes in paired diagnosis and relapse tumors from a pediatric high-grade glioma and four adult glioblastoma patients. We determined the full structures of the major double minutes using a novel approach combining multiple types of supporting genomic evidence. Among the double minutes identified in the pediatric tumor, only one carrying EGFR was maintained at high abundance in both samples, whereas two others were resent in only trace amounts at diagnosis but abundant at relapse, and the rest were found either in the relapse sample only or in the diagnosis sample only. For the EGFR-carrying double minutes, we found a secondary somatic deletion in all copies at relapse, after erlotinib treatment, but this was rare at diagnosis, suggesting potential resistance to the EGFR inhibitor. This mutation caused an in-frame RNA transcript to skip exon 16, a novel transcript absent in EST database and in about 700 brain tumors that we reviewed. We observed similar patterns involving longitudinal copy number shift of double minutes in another four pairs (diagnosis / relapse) of adult glioblastoma. Overall, in three of five paired tumor samples, we found that although the same oncogenes were amplified at diagnosis and relapse, they were amplified on different double minutes. Our results suggest that double minutes readily evolve, increasing tumor heterogeneity rapidly. Understanding patterns of double minute evolution can shed light on future therapeutic solutions to brain tumors carrying such variants.

  Study EGAS00001003212

• Transcriptome_human_nasal_epithelium

  1. Odors are detected, firstly, by olfactory sensory neurons (OSNs) in the olfactory epithelium of the nose. This neurons then project directly to the olfactory bulb in the brain. Olfaction depends on cellular regeneration of the OE, olfactory bulb and hippocampus, and on their continual re-wiring. The olfactory neural pathway includes regions of the frontal, temporal and limbic brain, which in turn overlap with brain areas involved in brain disorders. OSNs are the only aspect of the human brain exposed to the external environment. This not only makes them vulnerable to environmental changes, but also accessible for biomedical studies.We have already sequenced and developed a protocol for analyzing the transcriptome of mouse main olfactory epithelium and single OSNs. We propose here to perform a similar study for samples from the human olfactory epithelium. We have developed a minimally invasive method for obtaining human OSNs, among other cells from the nasal epithelium. In this experiment, we have obtained cell samples from the olfactory epithelium, including OSN, from healthy volunteers. We would like to further characterize them by RNA sequencing. This will give us valuable insight into human olfaction. It will also provide a first step into a new avenue to study, and find biomarkers for, brain diseases though the analysis of these easily available neurons. This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/

  Study EGAS00001001294

• Healthy_ageing_thymus

  Single cell RNA sequencing of immune and non-immune cells from healthy ageing thymus Thymus is a primary lymphoid organ that creates an environment for the T lymphocyte precursors differentiation into the naive T cells, which involves TCR gene rearrangement, negative and positive selection. Despite thymus critical function for the recognition of the pathogens it starts to atrophy very early in life. Thymic Epithelial Space (TES), where thymocyte education occurs, starts to decline rapidly just after birth, while with the onset of puberty thymus is also progressively replaced with adipose tissue. This leads to a reduced naive T cell output,which decreases an organism's ability to recognize pathogens. In our lab, we have already collected and characterized cell type composition and gene regulatory networks of the fetal tand adult human thymus (Park et al, Science 2020). In the current project we plan to expand the number of paediatric and adult samples in the study with the aim to understand how the process of thymic involution happens. We will use single-cell transcriptomics to zoom on changes that occur in immune and non-immune cell types in different phases of thymic involution with the hope to understand which gene expression changes are causal for the thymic involution process and how naïve T cell production can be increased in elderly. This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/

  Study EGAS00001004311

• Exome sequencing

  Human telomere biology disorders (TBD), a heterogeneous group of disorders characterized by telomere attrition and premature aging phenotypes, are caused by inherited loss-of-function mutations in telomere-associated genes. Here, we identify three germline heterozygous missense variants in RPA1 gene in four unrelated probands presenting with short telomeres and varying clinical features of TBD including bone marrow failure, myelodysplastic syndrome, T- and B-cell lymphopenia, pulmonary fibrosis, and skin manifestations. All variants cluster to DNA binding domain A of RPA1 protein. RPA1 is an essential single-strand DNA-binding protein essential for DNA replication and repair. RPA1 has been implicated in telomere maintenance but the mechanism remains elusive. Thus far, no genetic disorder had been linked to RPA1. Using FRET assays, we showed that RPA1E240K and RPA1V227A exhibit increased binding to single-strand and telomeric DNA, implying a gain in DNA-binding function while RPA1T270A has binding properties similar to wild type. To study the mutational effect, RPA1E240K, with the highest binding capacity, was knocked-in iPSCs using CRISPR/Cas9, which showed severe telomere shortening and impaired hematopoietic differentiation. Furthermore, in the RPA1E240K patient, stable blood counts over two decades due coincided with clonal rescue hematopoiesis with an RNA-degrading truncating RPA1 mutation and a uniparental isodisomy 17p with loss of RPA1E240K allele. Using single cell DNA sequencing, the two somatic genetic rescue events were proven to be independently acquired in hematopoietic stem cells. In summary, we describe the first human disease caused by germline RPA1 variants in individuals with TBD.

  Study EGAS00001005761

• Massachusetts General Hospital (MGH)/Broad Hurthle cell carcinoma whole exome sequencing study

  In this study, we performed whole-exome sequencing of 41 patients with Hurthle cell carcinoma, a thyroid cancer variant with abundant mitochondria. We were able to identify recurrent somatic mutations in both the nuclear and mitochondrial genomes of Hurthle cell carcinoma. Our study identifies mutations in DAXX (GeneID: 1616), TP53 ( GeneID:7157), NF1(GeneID:4763) , NRAS (GeneID:4893), CDKN1A (GeneID:1026), ARHGAP35 (GeneID:2909), the TERT (GeneID:7015) promoter, and mitochondrial-encoded complex I genes to be candidate driver events in Hurthle cell carcinoma. Furthermore, copy number analysis revealed widespread chromosomal losses, resulting in loss-of-heterozygosity and a near-haploid state, to be a defining feature of these tumors. Finally, by analyzing locoregional recurrences and metastases, we were able to identify that widespread chromosomal losses and mitochondrial complex I mutations appear to be early driver events that are selected during clonal evolution.

  Study phs001580

• Identification of 22 Novel Loci Associated with Susceptibility to Testicular Germ Cell Tumors

  Testicular germ cell tumors (TGCT) are the most common cancers in young men of European ancestry aged 20 to 39 years. The Testicular Cancer Consortium (TECAC) has brought together the largest genome-wise association study (GWAS) study of TGCT to date. We conducted a GWAS of 5,602 cases and 5,006 controls aggregated from 12 locations in the US and Europe. Logistic regression models adjusted for study center and genomic ancestry. Genotypes were imputed against the Human Haplotype Reference Consortium. Meta-analysis was performed to combine GWAS results with summary statistics from five previously published TGCT studies, UK Biobank, deCODE Genetics, and an independent set of cases and controls, for a total of 10,156 cases and 179,683 controls. 22 novel and 45 previously reported loci associated with TGCT surpassed genome-wide significance (p < 5e-08).

  Study phs001349

• Genomic Predictors of Response to Immune Checkpoint Therapy

  Immune checkpoint therapies, including monoclonal antibodies to programmed cell death-1 (PD-1) and cytotoxic % lymphocyte associated protein-4 (CTLA-4), yield durable clinical responses across many tumor types, including metastatic melanoma, non-small cell lung cancer (NSCLC), and renal cell carcinoma (RCC). However, predictors of response to these therapies in RCC are still unknown. Genomic characterization of large clinical cohorts of patients treated with anti-CTLA-4 and anti-PD-1 agents in melanoma and NSCLC have suggested that high mutational burden, high neoantigen burden, and high expression of certain genes in pre-treatment tumors may be associated with patient response to these therapies. In this study, we sought to investigate genomic predictors of response to anti-PD1 therapy in metastatic RCC in two independent clinical cohorts using whole exome and whole transcriptome sequencing.

  Study phs001493

• MP2PRT: Identification of Genetic Changes Associated with Relapse and/or Adaptive Resistance in Patients Registered as Favorable Histology Wilms Tumor on AREN03B2

  The Molecular Profiling to Predict Response to Treatment (MP2PRT) program is part of the NCI's Cancer Moonshot Initiative. The aim of this program is the retrospective characterization and analysis of biospecimens collected from completed NCI-sponsored trials of the National Clinical Trials Network and the NCI Community Oncology Research Program. This study, titled "Identification of Genetic Changes Associated with Relapse and/or Adaptive Resistance in Patients Registered as Favorable Histology Wilms Tumor on AREN03B2", performs genomic characterization (WGS 30X, Total RNAseq, miRNAseq) on a discovery set of 70 trio cases (normal tissue, tumor tissue at time of diagnosis, tumor tissue at time of relapse) from patients who relapsed with Favorable Histology Wilms Tumor. Prioritized findings from the discovery set will be validated using Targeted Sequencing in an independent validation set of 47 relapse samples.

  Study phs001965

• The Ultrasound Study of Tamoxifen

  The Ultrasound Study of Tamoxifen is a 12-month longitudinal study to describe volumetric breast density change over time among women with and without tamoxifen exposure. Women were enrolled at the Karmanos Cancer Institute and Henry Ford Health Systems in Detroit, Michigan between 2011-2014. Enrollment included women prescribed tamoxifen for clinical indication (n=82) and a comparison group of women frequency matched on age, race, and menopausal status (n=165). Whole breast ultrasound tomography (UST) scans were used to measure volume averaged sound speed (m/s) as a surrogate of volumetric breast density. Ultrasound tomography (UST) scans were completed at baseline prior to tamoxifen initiation and were repeated at 1-3 months, 4-6 months, and 12 months after tamoxifen initiation. For the comparison group, UST scans were completed at baseline and 12 months. Questionnaires were completed at each scan.

  Study phs003183

• National Institutes of Health H3Africa African Collaborative Center for Microbiome and Genomics Research (ACCME)

  The African Collaborative Center for Microbiome and Genomics Research is a multi-institutional collaborative research project. The objectives of the project are to collaborate and implement high impact integrative epidemiology and genomics research into discovery of biomarkers associated with cervical carcinogenesis. Specifically ACCME links and leverages existing funded research and program activities at the collaborating institutions to study the interaction between vaginal microbiome, host genetic factors and molecular variants of Human Papilloma Virus (HPV) to determine correlates of viral persistence in the causal pathway of cervical cancer, a major cause of preventable mortality in Nigeria and other parts of sub-Saharan Africa. This research offers several opportunities to advance understanding of cervical carcinogenesis, viral oncogenesis, new biomarker discovery and risk stratification by genotype in a cohort of African women. Sponsorship: This project is sponsored by the National Institutes of Health (NIH)

  Study phs001945