12291 results for ""statistically+reactive"+taxa+in+microbial+community"

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• Immunomodulatory effects and improved outcomes with cisplatin- vs carboplatin-based chemotherapy plus atezolizumab in urothelial cancer

  In metastatic urothelial cancer (mUC), cisplatin versus carboplatin leads to durable disease control in a subset of patients. The IMvigor130 trial reveals more favorable effects with atezolizumab combined with gemcitabine and cisplatin (GemCis) versus gemcitabine and carboplatin (GemCarbo). This study investigates the immunomodulatory effects of cisplatin as a potential explanation for these observations. Our findings indicate that improved outcomes with GemCis versus GemCarbo are primarily observed in patients with pretreatment tumors exhibiting features of restrained adaptive immunity. Additionally, GemCis versus GemCarbo ± atezolizumab induces transcriptional changes in circulating immune cells, including upregulation of antigen presentation and T-cell activation programs. In vitro experiments demonstrate that cisplatin, compared with carboplatin, exerts direct immunomodulatory effects on cancer cells, promoting dendritic cell activation and antigen-specific T cell killing. These results underscore the key role of immune modulation in cisplatin's efficacy in mUC and highlight the importance of specific chemotherapy backbones in immunotherapy combination regimens.

  Study EGAS50000000104

• Intervention with Micronutrients and Long-Term Impact in Brazil-RECODISA

  Intervention with Micronutrients and Long-Term Impact in Brazil, a partnership between the Federal University of Ceará, Brazil and the University of Virginia, USA, enrolled infants in the age group of 2-36 months to investigate trends in gastrointestinal infections and their effects on growth and development and to identify genetic factors contributing to these diseases.A total of 1044 children from six urban communities in Brazil's semiarid region, were enrolled during active surveillance; those with diarrhea (three or more liquid stools in the last 24 hours at enrollment) were defined as a cases and matched with controls having no diarrhea during the past two weeks (at enrollment) to evaluate their growth and development. A subset of 664 children with their genetic and associated phenotypic data is included in this submission. More information on this project and its related projects can be found here: Studies of diarrheal susceptibility, growth, and development, in pediatric populations in Northeastern Brazil

  Study phs003174

• Somatic Mutations and Cell Lineage in the Human Brain

  Genetic mutations causing human disease are conventionally thought to be inherited from one's parents and present in all somatic (body) cells. Increasingly however, somatic mutations are implicated in neurological diseases. Somatic mutations that arise during the cell divisions of prenatal brain development are inherited in clonal fashion and can cause neurodevelopmental diseases, even when present at low levels of mosaicism. In this study we use whole genome, RNA, and ATAC sequencing of single cells and bulk tissue to identify somatic mutations in control, and some disease, brains to: 1) identify and catalogue the mutations which shape the somatic neuronal genome; 2) perform a cell lineage analysis of the human brain using clonal somatic mutations in cortical neurons; 3) determine patterns of somatic mutations at different ages and in aging related disease phenotypes; and 4) relate cell lineage patterns to cell phenotype in the human brain through cell type-specific analyses.

  Study phs001485

• Integrative Age-Related Changes in Genome and Epigenome in Human Lung in Relation to Smoking

  The Integrative Age-Related Changes in Genome and Epigenome in Human Lung in Relation to Smoking study was designed to assess DNA methylation and gene expression profiles in cytologically normal bronchial progenitor "basal" cells. The cells were collected from 54 consented bronchoscopy specimen donors at standard airway locations during clinically indicated bronchoscopy, and then outgrown in primary cultures. DNA methylation profiles were assessed using Enzymatic-Methyl sequencing (EM-seq: 96% genomic coverage, 7.5x depth) in all 54 donors' samples. The gene expression profile was evaluated by bulk RNA-Seq in 39 donors' samples. The study participants were at the ages of 33 - 81 years old at enrollment. Of the 54 donors, 31 were newly diagnosed with lung cancer. As for tobacco smoke exposure, there were 19 current, 18, former, and 17 never smokers. There are 26 subjects whose specimens were used for single cell whole-genome sequencing study phs002758.

  Study phs003317

• A Translational, Pharmacodynamic and Pharmacokinetic Phase IB Clinical Study of Everolimus in Resectable Non-Small Cell Lung Cancer

  This phase IB clinical trial studied the pharmacodynamic changes induced by everolimus in patients with previously untreated, resectable non small cell lung cancer. Using a combination of in vivo and ex vivo assessments with FDG PET, immunohistochemistry and genomic assays, evidence of mTOR pathway perturbation was assessed in patients treated with everolimus, an allosteric mTOR inhibitor. Untreated patients served as controls for comparison. Key results from this work include a dose-dependent biologic effect of everolimus, signal of activity in RAS mutant tumors as well as near complete metabolic and pathologic response in a case of sarcomatoid lung cancer. These findings represent novel translational insights that can guide future development of mTOR inhibitors in lung cancer and other tumor types. Additionally, metabolic response and anatomic tumor shrinkage observed in a significant proportion of patients following a short of duration of therapy with everolimus suggests potential clinical utility of this agent in carefully-selected lung cancer patients.

  Study phs000829

• Hofer et al., A specific subpopulation of cancer-associated fibroblasts promotes resistance to chemotherapy in triple-negative breast cancer by upregulating G0S2 protein

  Chemotherapy is the standard of care for patients with triple-negative breast cancer (TNBC), but the mechanisms of chemoresistance remain poorly understood. Here, we investigated the role of cancer associated fibroblasts (CAFs) in the chemotherapy response of TNBC, by combining in vivo analyses of TNBC patients with ex vivo cancer modeling, using tumor-on-chip (ToC) technology. Transcriptomic analysis revealed that the proportion of a specific CAF population, the extracellular matrix-producing myofibroblasts (ECM-myCAFs), is reduced after chemotherapy in chemo-sensitive, but not in chemo-resistant TNBC patients. In ToC devices, primary ECM-myCAFs promoted TNBC cell survival under Doxorubicin and Paclitaxel treatment. The mechanism of chemoresistance was elucidated by using single-cell RNA sequencing, advanced cell imaging and functional assays: ECM-myCAFs upregulate the G0/G1 switch 2 (G0S2) protein in TNBC cells, via activation of SRC family kinases. Altogether, our work identifies G0S2 as a new player in CAF mediated chemotherapy resistance in TNBC.

  Study EGAS50000000886

• 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

• Novel mutational mechanisms and drivers in Pancreatic Neuroendocrine Tumours

  Pancreatic neuroendocrine tumours (PanNETs) are increasing in prevalence due to earlier detection, consequently creating challenges in clinical care, as current classification permits unsatisfactory therapeutic stratification. We performed whole genome sequencing of 102 primary PanNETs and defined the genomic events underlying their pathogenesis. We describe the mutational signatures they harbour, including a novel G:C>T:A Base-Excision-Repair-deficiency signature due to MUTYH inactivation. We uncover a larger than expected proportion of germline mutations in clinically sporadic PanNETs. These include previously unreported mutations in DNA repair genes MUTYH, CHEK2, BRCA2, and PALB2, which together with MEN1 and VHL occur in 16% of patients. Somatic mutations (point mutations and structural rearrangements) commonly occurred in genes involved in 4 main pathways: chromatin remodelling, DNA damage repair, activation of mTOR signalling (including novel EWSR1 gene fusions) and telomere maintenance. Aberrations in these mechanisms are associated with subtypes of PanNET with potential clinical application for prognostic and therapeutic stratification.

  Study EGAS00001001732

• CTCF/cohesin-binding sites are frequently mutated in cancer

  Cohesin is present in almost all active enhancer regions, where it is associated with transcription factors. Cohesin frequently colocalizes with CTCF (CCCTC-binding factor), affecting genomic stability, expression and epigenetic homeostasis. Cohesin subunits are mutated in cancer, but CTCF/cohesin-binding sites (CBSs) in DNA have not been examined for mutations. Here we report frequent mutations at CBSs in cancers displaying a mutational signature where mutations in A•T base pairs predominate. Integration of whole-genome sequencing data from 213 colorectal cancer (CRC) samples and chromatin immunoprecipitation sequencing (ChIP-exo) data identified frequent point mutations at CBSs. In contrast, CRCs showing an ultramutator phenotype caused by defects in the exonuclease domain of DNA polymerase ɛ (POLE) displayed significantly fewer mutations at and adjacent to CBSs. Analysis of public data showed that multiple cancer types accumulate CBS mutations. CBSs are a major mutational hotspot in the noncoding cancer genome.

  Study EGAS00001003010

• MGMT genomic rearrangements contribute to chemotherapy resistance in gliomas

  Temozolomide (TMZ) is an oral alkylating agent used for the treatment of glioblastoma and is now becoming a chemotherapeutic option in patients diagnosed with high-risk low-grade gliomas1. The O-6-methylguanine-DNA methyltransferase (MGMT) is responsible for the direct repair of the main TMZ-induced toxic DNA adduct, the O6-Methylguanine lesion. MGMT promoter hypermethylation is currently the only known biomarker for TMZ response in glioblastoma patients2. Here we show that a subset of recurrent gliomas carry MGMT genomic rearrangements that lead to MGMT overexpression, independently from changes in its promoter methylation. By leveraging the CRISPR/Cas9 technology we generated some of these MGMT rearrangements in glioma cells and demonstrated that they lead to TMZ resistance both in vitro and in vivo. Lastly we showed that such fusions can be detected in tumor-derived exosomes and could potentially represent an early detection marker of tumor recurrence in a subset of patients treated with TMZ.

  Study EGAS00001004544