4836 results for "*oma"

in 19.06 milliseconds.

• Y90 radioembolization followed by intravenous Nivolumab for advanced hepatocellular carcinoma

  To evaluate the efficacy of combination therapy with ICI and RT in patients, a Phase II trial (CA209-678) was conducted to investigate the efficacy and safety of Y90-RE followed by nivolumab in patients with advanced HCC (NCT03033446, n = 36). Interestingly, the ORR was found to be 30.6% in all patients and 43.5% when restricted to patients with only intrahepatic tumors, suggesting possible synergism between Y90-RE and ICI. Here we present whole exome sequencing (WES) and RNA-seq data for 33 patients treated with Y90 radioembolization followed with Nivolumab.

  Study EGAS00001006834

• Identification and functional characterisation of a rare MTTP variant underlying familial non-alcoholic fatty liver disease

  We identified a rare causal variant in MTTP, c.1691T>C p.I564T (rs745447480) encoding microsomal triglyceride transfer protein (MTP) causing progressive non-alcoholic fatty liver disease with cirrhosis and hepatocellular carcinoma unrelated to metabolic syndrome, without manifestations of abetalipoproteinemia, in a four generation family with South Asian ancestry. Variant-expressing hepatocyte-like-cells (HLCs) derived from human induced pluripotent stem cells generated from homozygous donor skin fibroblasts had lower lipoprotein ApoB secretion, compared to wild type cells. Cytoplasmic triglyceride accumulation in HLCs triggered endoplasmic reticulum stress, secretion of pro-inflammatory mediators, production of reactive oxygen species, delineating the progression of disease associated with homozygosity for MTTP p.I564T

  Study EGAS00001005254

• TK-EPN862 - Patient-dervied xenograft model of Posterior Fossa A Ependymoma - RNAseq

  Ependymomas (EPN) are the third most common malignant brain cancer in children. Treatment strategies for pediatric EPN have remained unchanged over recent decades, with 10-year survival rates stagnating at just 67% for children aged 0-14 years. Moreover, patients who survive treatment for the most common subtype of pediatric EPN (posterior fossa A (PFA)), often suffer long-term neurological side effects as a result of therapy. It is evident that there is a need for safer, more effective treatments for pediatric EPN patients. There are ten distinct subgroups of EPN, each with their own molecular and prognostic features. To identify and facilitate the testing of new treatments for EPN, in vivo laboratory models representative of the diverse molecular subtypes are required. Here, we describe the establishment of a patient-derived orthotopic xenograft (PDOX) model of PFA EPN, derived from a metastatic cranial lesion. Patient and PDOX tumors were analyzed using immunohistochemistry, DNA methylation profiling, whole genome sequencing (WGS) and RNA sequencing. Both patient and PDOX tumors classified as PFA EPN by methylation profiling, and shared similar histological features consistent with this molecular subgroup. RNA sequencing revealed that gene expression patterns were maintained across the primary and metastatic tumors, as well as the PDOX. Copy number profiling revealed gains of chromosomes 7, 8 and 19, and loss of chromosomes 2q and 6q in the PDOX and matched patient tumor. No clinically significant single nucleotide variants were identified, consistent with the low mutation rates observed in PFA EPN. Overexpression of EZHIP RNA and protein, a common feature of PFA EPN, was also observed. Despite the aggressive nature of the tumor in the patient, this PDOX was unable to be maintained past two passages in vivo. Others who have successfully developed PDOX models report some of the lowest success rates for EPN compared to other pediatric brain cancer types attempted, with loss of tumorigenicity not uncommon, highlighting the challenge in propagating these tumors in the laboratory. Here, we discuss our collective experiences with PFA EPN PDOX model generation and propose potential approaches to improve future success in establishing preclinical EPN models

  Study EGAS00001006844

• Population_based_analysis_of_POT1_variants_in_a_cutaneous_melanoma_case_control_cohort

  Pathogenic germline variants in the protection of telomeres 1 gene (POT1) have been associated with predisposition to a range of tumor types, including melanoma, glioma, leukemia and cardioangiosarcoma. We sequenced all coding exons of the POT1 gene in 2,929 European-descent melanoma cases and 3,298 controls, identifying 43 protein-changing genetic variants. We performed functional studies on each of these variants and explored their possible contribution to disease risk.

  Study EGAS00001006870

• WGS of MAPKi acquired resistant samples from patients and PDX models

  Blocking cancer genomic instability, which generates diverse variants that enable rapid adaptations, may prevent tumor escape from therapies. We show that, after MAPK inhibitor (MAPKi) therapy in patients and patient-derived xenografts, acquired-resistant genomes of metastatic cutaneous melanoma accumulate amplicons of resistance-driver, non-homologous end-joining (NHEJ), and homologous recombination repair (HRR) genes within complex genomic rearrangements (CGRs) and extrachromosomal circular DNAs (ecDNAs). Also, chromothriptic genomic regions enrich for mutations and may engender ecDNAs and CGRs. Overall, somatic mutations within ecDNA- and CGR-amplicons enrich for HRR signatures, and, in acquired resistance, ecDNA (versus CGR) mutations enrich for APOBEC3 signatures. Breakpoint-sequence analysis suggests NHEJ as critical to double-stranded DNA break repair underlying CGR and ecDNA formation. In vivo, NHEJ-targeting by a DNA-PKCS inhibitor prevented acquired MAPKi-resistance by reducing the size of ecDNAs and CGRs early on combination treatment. Thus, targeting the cause(s), as opposed to the consequences, of genomic instability prevents acquired resistance.

  Study EGAS00001006874

• Tracing early predictors of glioma evolution under therapy

  Clonal evolution drives cancer progression and therapeutic resistance. Recent studies revealed divergent longitudinal trajectories in gliomas, but early molecular traits steering post-treatment cancer evolution remain unclear. We analyzed sequencing data of 544 initial-recurrent adult diffuse glioma pairs to identify genomic and transcriptomic early predictors of tumor evolution in each molecular subtype.

  Study EGAS00001006894

• Vitamin C boosts DNA demethylation in TET2 germline mutation carriers

  We recently identified a family with lymphoma predisposition where a heterozygous truncating germline mutation in TET2 segregated with nodular lymphocyte predominant Hodgkin lymphoma. In a clinical trial of one year, we investigated the effects of oral 1 g/day vitamin C supplementation on DNA methylation by analyzing genome-wide DNA methylation and gene expression patterns from the family members.

  Study EGAS00001006916

• Genomic profiling of localized (lFL) and systemic follicular lymphoma (sFL) reveals novel insights into FL pathogenesis

  At diagnosis, the majority of FL presents with symptomatic disease in advanced/systemic stages of FL (sFL). In contrast only around 10 to 15% of cFL are diagnosed in localized stages (lFL). The biological knowledge is mainly based on data derived from global sFL analysis and only small cohorts of lFL were characterized intensively so far. It is well-known that the hallmark BCL2 translocation is less frequently observed in lFL. Furthermore, lFL differs from sFL concerning their gene expression and their N-glycosylation profiles. In consequence, comprehensive global analysis with CNA profiling and whole exome sequencing was performed in a large cohort of lFL. Additionally, the mutational profile as well as the CNA landscape of lFL and sFL, as well as for BCL2 translocation-positive and -negative was compared.

  Study EGAS00001006927

• Multiome_HB

  Hepatoblastoma (HB) cells display strong phenotypic heterogeneity with a major impact on drug response, but the underlying mechanisms are poorly understood. Here, we use a single-cell multi-omic strategy to unravel the molecular determinants of this plasticity. HB display a continuum of single-cell states between hepatocytic (scH), liver progenitor (scLP) and mesenchymal (scM) differentiation poles, with an intermediate scH/LP population bordering scLP and scH areas in spatial transcriptomics. Chromatin accessibility landscapes reveal the gene regulatory networks of each differentiation pole, and the sequence of transcription factor activation underlying cell state transitions. Single-cell mapping of somatic alterations reveals the clonal architecture of each tumor, showing that each genetic subclone displays its own range of cellular plasticity across differentiation poles. The most scLP subclones, overexpressing stem cell and DNA repair genes, proliferate faster after neo-adjuvant chemotherapy. These results highlight how the interplay of clonal evolution and epigenetic plasticity shapes the potential of HB subclones to respond to chemotherapy.

  Study EGAS00001006932

• The immunological characterization of expanded tumor-infiltrating lymphocytes in renal cell carcinoma patients

  In this study, we comprehensively characterized the non-expanded and expanded tumor-infiltrating lymphocytes (TILs) from treatment-naïve RCC patients, as well as the corresponding “young” TILs (pre-REP TILs) and “rapidly expanded” TILs (REP TILs) following a clinical-grade TIL production protocol. From our scRNA+TCRαβ-seq and TCRβ-seq analyses, we show that the REP protocol preferentially favors the expansion CD4+ T-cells that originate from small T-cell clones in the tumor microenvironment (TME), indicating that the large, exhausted T-cell clones in the tumor do not expand during the protocol. We further identified RCC-associated TCR motifs that were validated in multiple TCRαβ-seq and scRNA+TCRαβ-seq datasets, as well as quantified the RCC-associated TCRs from the REP protocol. Overall, the T-cells carrying the RCC-associated TCRs remained high in the tumors and corresponding pre-REP TILs, but the frequency was reduced in the REP TILs. Furthermore, the overall anti-viral TCRs remained low throughout the REP protocol. Our results provide an in-depth understanding of the origin, phenotype, and specificity of the TCRs in RCC TILs.

  Study EGAS00001006952