543 results for "Daguerre+Crater+floor+materials+origin+nearby+crater+Chinese+name"

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• Esophageal Squamous Cell Carcinoma Precursor Study

  Esophageal cancer is the sixth most common cause of cancer death in the world. High-risk areas occur across central Asia and from eastern to southern Africa, and in these populations, nearly all of the cases are esophageal squamous cell carcinoma (ESCC). ESCC has a dismal prognosis, largely because symptoms usually appear late in the course of the disease, when the tumors are incurable. Early detection and treatment of curable precursor lesions and early invasive ESCC in asymptomatic high-risk adults offers the potential for long-term survival and reduced mortality from this disease. Previous studies have shown that routine cytology of non-endoscopically collected esophageal cell samples is not sensitive and specific enough to be clinically useful, so we are now looking for molecular markers of high-grade esophageal squamous dysplasia (HGD), the proven clinically important precursor lesion of ESCC, that can be used to increase the accuracy and utility of this initial screening exam. National Cancer Institute (NCI) and Cancer Institute and Hospital, Chinese Academy of Medical Sciences (CAMS) began collaborative studies of ESCC since the mid-1980s in China. The present proposal is designed to characterize the type and prevalence of DNA mutations in tissue samples of HGD and to establish biologic and questionnaire resources for further study. The proposed study has two components, a field study to obtain questionnaire data and biological samples, and a genomic analysis to perform sequencing of the biological samples and bioinformatics analysis of the sequencing. 

  Study phs002814

• RNA-Seq data of hepatoma (Huh7 derived) and Ph5CH cells and primary hepatocytes

  The innate immune response of cells of hepatic origin (Huh7, Huh7.5, PH5CH and primary human hepatocytes (PHH), 66 samples) was analyzed by transcriptome analysis (RNAseq) upon supernatant delivery or transfection of synthetic dsRNA (poly(I:C)). Expression of TLR3 and RIG-I was reconstituted by lentiviral transduction in Huh7 and Huh7.5 cells. The sequencing is single RNA-Seq on an Illumina HiSeq 4000 with the Illumina TruSeq stranded mRNA kit.

  Dataset EGAD00001007083

• Exploiting New Patterns of Genome Damage in Triple Negative Breast Cancer

  Genomic instability, a feature of triple negative breast cancers (TNBC), represents an opportunity for discovery of biologic and clinically relevant subgroups of patients. Owing to TP53 mutation in the majority of cases, DNA repair deficiency through loss of BRCA1 and BRCA2, and by expression features patterning a basal cell of origin, TNBC represents a molecularly and clinically distinct group of breast cancer patients. Unfortunately, targetable molecular features of TNBC remain elusive and TNBC patients suffer the poorest outcomes amongst clinical subgroups. Within TNBC patients, responses to treatment vary and although gene expression patterns within TNBC have been identified, little progress has been made in developing biomarkers; effective stratification as a route to directing patients to more targeted therapy is lacking. In this study, we exploit mutational processes in TNBC as a new opportunity to stratify patients and to understand the evolutionary progression of TNBC cells harboring specific DNA repair properties.

  Study phs003038

• Inactivation of TGFβ receptors in stem cells drives cutaneous squamous cell carcinoma - 30 whole exomes

  Melanoma patients treated with oncogenic BRAF inhibitors can develop cutaneous squamous cell carcinoma (cSCC) within weeks of treatment, driven by paradoxical RAS/RAF/MAPK pathway activation. Here, we identify frequent TGFBR1 and TGFBR2 mutations in human vemurafenib-induced skin lesions and in sporadic cSCC. Functional analysis reveals these mutations ablate canonical TGFβ Smad signaling which is localised to bulge stem cells in both normal human and murine skin. MAPK pathway hyperactivation (through BrafV600E or KrasG12D knockin) and TGFβ signaling ablation (through Tgfbr1 deletion) in LGR5+ve stem cells enables rapid cSCC development in the mouse. Mutation of Tp53 (which is commonly mutated in sporadic cSCC) coupled with Tgfbr1 deletion in LGR5+ve cells also results in cSCC development. These findings indicate that LGR5+ve stem cells can act as cells of origin for cSCC and that RAS/RAF/MAPK pathway hyperactivation or Tp53 mutation, coupled with loss of TGFβ signaling, are driving events of skin tumorigenesis.

  Study EGAS00001001892

• Transcriptional and functional profiling defines human small intestinal macrophage subsets

  Macrophages (Mf) are instrumental in maintaining immune homeostasis in the intestine, yet studies on origin and heterogeneity of human intestinal Mf are scarce. Here, we identified four distinct Mf subpopulations in human small intestine (SI). Assessment of their turnover in duodenal transplants revealed that all Mf subsets were completely replaced over time; Mf1 and Mf2, phenotypically similar to peripheral blood monocytes (PBMo), were largely replaced within 3 weeks, whereas two subsets with features of mature Mf, Mf3 and Mf4, exhibited significantly slower replacement. Mf3 and Mf4 localized differently in SI; Mf3 formed a dense network in mucosal lamina propria, whereas Mf4 was enriched in submucosa. Transcriptomic analysis showed that all Mf subpopulations subsets were markedly distinct from PBMo and dendritic cells (DC). Compared to PBMo, Mf subpopulations showed reduced responsiveness to proinflammatory stimuli, but were proficient at endocytosis of particulate and soluble material. These data provide a comprehensive analysis of human SI Mf population and suggest a precursor-progeny relationship with PBMo.

  Study EGAS00001002093

• Genomic analyses of gynecologic carcinosarcomas reveal frequent mutations in chromatin remodeling genes

  Malignant Mixed Müllerian Tumors, also known as carcinosarcomas, are rare tumors of gynecological origin. Here we perform whole exome analyses of 22 tumors using massively parallel sequencing to determine the mutational landscape of this tumor type. On average, we identify 43 mutations per tumor, excluding four cases with a mutator phenotype that harbored inactivating mutations in mismatch repair genes. In addition to mutations in TP53 and KRAS, we identify genetic alterations in chromatin remodeling genes, ARID1A and ARID1B, in histone methyltransferase MLL3, in histone deacetylase modifier SPOP, and in chromatin assembly factor BAZ1A, in nearly two thirds of cases. Alterations in genes with potential clinical utility are observed in more than three quarters of the cases and included members of the PI 3-kinase and homologous DNA repair pathways. These findings highlight the importance of the dysregulation of chromatin remodeling in carcinosarcoma tumorigenesis and suggest new avenues for personalized therapy.

  Study EGAS00001000941

• Methylome sequencing of cell-free DNA and RRBS of solid tissue

  Early cancer detection by cell-free DNA (cfDNA) faces multiple challenges: low fraction of tumor cfDNA, molecular heterogeneity of cancer, and sample sizes not sufficient to reflect diverse patient population. We develop a cancer detection approach to address these challenges. It consists of an assay, cfMethyl-Seq, for cost-effective sequencing of cfDNA methylome (with >12-fold enrichment over whole genome bisulfite sequencing in CpG islands), and a computational method to extract methylation information and diagnose patients. Applying our system to 408 colon, liver, lung, and stomach cancer patients and controls, at 97.9% specificity we achieve 80.7% and 74.5% sensitivity in detecting all-stage and early-stage cancer, and 89.1% and 85.0% accuracy for locating tissue-of-origin of all-stage and early-stage cancer, respectively. Our approach cost-effectively retains methylome profiles of cancer abnormalities, thereby permitting the classification models to learn new features as training cohorts grow, and expanding their scope to other cancer types.

  Study EGAS00001006020

• Ductal keratin 15+ luminal progenitors in normal breast exhibit a basal-like breast cancer transcriptomic signature

  Normal breast luminal epithelial progenitors have been implicated as cell of origin in basal-like breast cancer, but their anatomical localization remains understudied. Here, we combine micro-collection of uncultured organoids and single cell mRNA sequencing (scRNA-seq) of FACS-sorted luminal epithelial cells with multicolor imaging to profile ducts and terminal ductal lobular units (TDLUs) and compare them with breast cancer subtypes. Unsupervised clustering reveals eleven distinct clusters and a differentiation trajectory starting with keratin 15+ (K15+) progenitors enriched in ducts. Spatial mapping of luminal progenitors is confirmed at the protein level by staining with critical duct markers. Comparison of the gene expression profiles of normal luminal cells with those of breast cancer subtypes reveals a strong correlation between normal breast K15+ ductal progenitors and basal-like breast cancer. We propose that K15+ basal-like breast cancers originate in ductal progenitors, which emphasizes the importance of not only lineages but also cellular position within the ductal-lobular tree.

  Study EGAS00001005963

• Chromosomal copy number heterogeneity predicts survival rates across cancers

  Survival rates of cancer patients vary widely within and between malignancies. While genetic aberrations are at the root of all cancers, individual genomic features cannot explain these distinct disease outcomes. In contrast, intra-tumour heterogeneity (ITH) has the potential to elucidate pan-cancer survival rates and the biology that drives cancer prognosis1,2. Unfortunately, a comprehensive and effective framework to measure ITH across cancers is missing3. Here, we introduce a scalable measure of chromosomal copy number heterogeneity that predicts patient survival across cancers. We show that the level of ITH can be derived from a single-sample copy number profile. Using gene-expression data we demonstrate that ongoing chromosomal instability underlies the observed heterogeneity. Analysing 11,534 primary cancer samples from 35 different malignancies, we find that copy number heterogeneity can be accurately deduced and predicts cancer survival across tissues of origin and stages of disease. Our results provide a unifying molecular explanation for the different survival rates observed between cancer types.

  Study EGAS00001004702

• Rna-Seq Leiomyosarcoma subtypes

  Leiomyosarcomas (LMS) are genetically heterogeneous tumors differentiating along smooth muscle lines. Currently, LMS treatment is not informed by molecular subtyping and is associated with highly variable survival. While disease site continues to dictate clinical management, the contribution of genetic factors to LMS subtype, origins, and timing are unknown. Here we analyzed 70 genomes and 130 transcriptomes of LMS, including multiple tumor regions and paired metastases. Molecular profiling highlighted the extremely early origins of LMS. Three specific subtypes of LMS develop from distinct lineages of smooth muscle cells. Of these, dedifferentiated LMS with high immune infiltration and tumors primarily of gynaecological origin acquired the highest burden of genomic mutation and are associated with worse survival. Homologous recombination defects lead to genome-wide mutational signatures, and a corresponding sensitivity to PARP and other DNA damage response inhibitors, suggesting a novel therapeutic strategy for LMS. Finally, by phylogenetic reconstruction, we present evidence that clones seeding lethal metastases arise decades prior to LMS diagnosis.

  Study EGAS00001004783