2638 results

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• Genome-wide expression profiles to compare array-based, RNAseq and NanoString technologies in patients with resected pancreatic ductal carcinoma.

  Using formalin-fixed paraffin embedded (FFPE) tissues collected prospectively in patients with resected pancreatic ductal carcinoma (PDC) we generated genome-wide expression profiles to compare array-based, RNAseq and NanoString technologies. Samples included in the study were collected 17 patients. After careful selection by the pathologist of 17 malignant cells-enriched, 7 stroma-enriched, and 6 normal (normal pancreas in 4 cases and normal duodenum in 2 cases) regions, sections were macrodissected, and total RNA extracted. Two additional FFPE-frozen matched-paired PDAC from our local Biobank were included. Our study represents the most extensive work comparing three technologies to generate gene expression profiles from FFPE samples, and provides technical guidance for future biomarker studies in samples collected prospectively in the context of clinical trials.

  Study EGAS00001002501

• Pharmacogenomic landscape of patient-derived cells informs precision oncology therapy

  Outcomes of anticancer therapy vary dramatically among patients, which may be caused by the specific molecular alterations in each patient’s tumor. Precision oncology aims to apply optimal therapies for each tumor based on its molecular characteristics. We have established a resource reporting the genomic and transcriptomic profiles of 462 patient tumor-derived cells (PDCs) across 14 cancer types, together with responses to 60 targeted agents. Compared with long-term cultured cancer cell lines, PDCs better recapitulate the molecular profiles of the original tumors. Among other unreported associations, we identify molecular factors inducing resistance to EGFR inhibitors in glioblastoma, and we suggest repurposing ibrutinib (currently used in hematological malignancies) for EGFR-specific therapy in gliomas. Lastly, using a retrospective clinical study, we find that PDC-derived sensitivities can be used to predict patient responses.

  Study EGAS00001002515

• Orthotopic Patient-Derived Xenografts of Pediatric Solid Tumors

  Pediatric solid tumors arise from endodermal, ectodermal, or mesodermal lineages. Although the overall survival of children with solid tumors is 75%-80%, that of children with recurrent disease is below 30%. To capture the complexity and diversity of pediatric solid tumors and establish new models of recurrent disease, we developed a protocol to produce orthotopic patient-derived xenografts (O-PDXs) at diagnosis, recurrence, and autopsy. Tumor specimens were received from 168 patients, and 64 O-PDXs were established for 12 types of pediatric solid tumors. The origins of the O-PDX tumors were reflected in their gene-expression profiles and epigenomes. Genomic profiling of the tumors, including detailed clonal analysis, was performed to determine whether the clonal population in the xenograft recapitulated the patient’s tumor. We identified several drug vulnerabilities and showed that the combination of a WEE1 inhibitor (AZD1775), irinotecan, and vincristine can lead to complete response in multiple rhabdomyosarcoma O-PDX tumors in vivo.

  Study EGAS00001002528

• Integrative single-cell and cell-free plasma RNA transcriptomics elucidates placental cellular dynamics

  The human placenta is a dynamic and cellular heterogeneous organ, which is critical in fetomaternal homeostasis and the development of preeclampsia. Previous work has shown that placenta-derived cell-free RNA increases during pregnancy. We applied large-scale microfluidic single-cell transcriptomic technology to comprehensively characterize cellular heterogeneity of the human placentas and identified multiple placental cell-type–specific gene signatures. Analysis of the cellular signature expression in maternal plasma enabled noninvasive delineation of the cellular dynamics of the placenta during pregnancy and the elucidation of extravillous trophoblastic dysfunction in early preeclampsia.

  Study EGAS00001002449

• Whole genome sequencing identified biomarker of response to PD1 blockade in Natural-killer/T-cell lymphoma

  WGS data of 13 and TCS data of 8 NKTCL patients. Significant association of PD-L1 rearrangements with objective response to anti-PD1 (pembrolizumab).

  Study EGAS00001002420

• The DNA methylation landscape of glioblastoma disease progression shows extensive heterogeneity in time and space

  Glioblastoma is characterized by widespread genetic and transcriptional heterogeneity, yet little is known about the role of the epigenome in glioblastoma disease progression. Here, we present genome-scale maps of DNA methylation in matched primary and recurring glioblastoma tumors, using data from a highly annotated clinical cohort that was selected through a national patient registry. We demonstrate the feasibility of DNA methylation mapping in a large set of routinely collected FFPE samples, and we validate bisulfite sequencing as a multipurpose assay that allowed us to infer a range of different genetic, epigenetic, and transcriptional characteristics of the profiled tumor samples. On the basis of these data, we identified subtle differences between primary and recurring tumors, links between DNA methylation and the tumor microenvironment, and an association of epigenetic tumor heterogeneity with patient survival. In summary, this study establishes an open resource for dissecting DNA methylation heterogeneity in a genetically diverse and heterogeneous cancer, and it demonstrates the feasibility of integrating epigenomics, radiology, and digital pathology for a national cohort, thereby leveraging existing samples and data collected as part of routine clinical practice.

  Study EGAS00001002538

• Inhibiton of the GABPB1L-containing GABP tetramer is sufficient to reverse replicative immortality in TERT promoter mutant glioblastoma cells.

  Over 50 types of cancer acquire TERT promoter mutations. These single point mutations reactivate telomerase, allowing for indefinite maintenance of telomere length and enabling cellular immortalization. The transcription factor binding site created by the point mutations specifically recruit the ETS factor GABP, a multimeric transcription factor composed of the GABPα and GABPβ subunits. GABP can form two functionally independent transcription factor species – a dimer or a tetramer – depending on which of the structurally distinct GABPβ isoforms is incorporated into the complex. In this study, we show that genetic disruption of GABPβ1L, a tetramer forming isoform of GABPβ that is dispensable in normal development, results in TERT silencing in a TERT promoter mutation dependent manner. Failure to activate TERT expression by GABPβ1L culminates in telomere dysfunction, DNA damage, and mitotic cell death exclusively in TERT promoter mutant cells. Furthermore, exogenous expression of TERT is sufficient to prevent telomere degradation and loss of cell viability in GABPβ1L-reduced lines bearing the mutant TERT promoter. Orthotopic injection of tetramer-deficient mutant TERT promoter GBM cells rendered lower tumor burden and prolonged the overall survival of the tumor-bearing mice. These results highlight the potentially widespread role of GABPB1L in enabling replicative immortality of TERT promoter cancers.

  Study EGAS00001002582

• Identification of a Fumarate-Hydratase Deficient-like RCC Subtype with Convergent Pathway Alterations

  The development of molecularly targeted therapies builds upon the identification of tumor clades with shared molecular abnormalities. Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a familial syndrome resulting from germline mutation of the two-hit tumor suppressor gene, Fumarate Hydratase (FH). HLRCC renal tumors present often in young adults, exhibit unique histological features and are particularly aggressive. HLRCC is uncommon and poorly understood, and whether there are sporadic renal tumors with similar characteristics, is unclear. Notably, FH can also be inactivated somatically in RCC, and should be included among FH-deficient (FHD) kidney tumors. We identified a tumor clade without FH mutations but with similar morphological and molecular characteristics as well as aggressive clinical behavior, which we name FHDL (FHD-like). We show that FHD/FHDL tumors represent a unique subtype of CIMP (CpG Island Methylator Phenotype) with the highest levels of overall genome methylation and CDKN2A silencing. FHD/FHDL tumors are characterized by convergent activation of the Hippo pathway as determined by frequent and mutually exclusive mutations in NF2 and PTPN14. AKR1B10, an NRF2 target, was upregulated in FHD/FHDL tumors as well as GATA3, which suggests a shared origin in the renal medulla and is consistent with topological studies. There is loss of 5-hydroxymethylcytosine in both FHD and FHDL tumors. These data define a group of particularly aggressive renal cancers with shared molecular features and potential targets for therapeutic intervention.

  Study EGAS00001002646

• DEEP IHEC release 2017

  Raw data files for DEEP's IHEC/EpiRR submission of 2017. metadata available at: http://deep.dkfz.de/#/experiments

  Study EGAS00001002655

• Spatial tumor microenvironment characterization and outcome of relapsed/refractory classic Hodgkin lymphoma

  About half of relapsed or refractory classic Hodgkin lymphoma (r/r CHL) patients succumb to their disease after high dose chemotherapy followed by autologous stem cell transplantation (HDT/ASCT). Here, we aimed at describing spatially resolved tumor microenvironment (TME) ecosystems to establish novel biomarkers associated with treatment failure in r/r CHL.

  Study EGAS00001007261