4911 results for "*oma"

in 15.29 milliseconds.

• Exome Sequencing to Define the Landscape of Plasma Cells in Systemic Light chain Amyloidosis

  Systemic light chain amyloidosis (AL) is characterized by the deposition of immunoglobulin light chains as amyloid fibrils in different organs, where they form toxic protein aggregates. The underlying disease is a plasma cell disorder, but limited whole exome data are available. We report the findings of an exome sequencing study in AL to define a plasma cell signature and compare this to monoclonal gammopathy of undefined significance (MGUS) and myeloma (MM). Twenty-four samples from unselected newly diagnosed untreated AL patients were analysed. CD138+ cells were isolated from bone marrow cells using MACSorting (Miltenyi Biotech, Bisley, UK). Cells were lysed in RLT+ buffer and DNA/RNA extracted using the AllPrep kit (Qiagen, Manchester, UK). Peripheral blood was isolated from patients, white blood cells purified by Ficoll-Pacque and DNA extracted using the QIAamp DNA mini kit (Qiagen). There were a median of 47 acquired nonsynonymous variants (range 4-253) per patient. Thirty percent of patients yielded a mutation in a myeloma driver gene. These mutations were either clonal or sub-clonal. There was evidence of MAPK activation with NRAS mutations, NF-κB activation and DNA repair pathway alterations. Exome data were used to determine the cytogenetic groups of AL samples and identified hyperdiploidy in 33% of cases and t(11;14) in 33% of cases. All translocations were generated via class switch recombination and breakpoints on chromosome 11 fell into the expected regions. A novel translocation, unlikely to be driving disease progression was identified involving RCC1. Finally, further analysis of the APCS gene encoding for the SAP protein did not show any biased genotype in the AL population in comparison to the general population. We conclude that exome sequencing identifies a genetic make-up of AL that is similar to other plasma cell disorders such as MM and MGUS. This not only includes copy number abnormalities and translocations but also nonsynonymous mutations.

  Study EGAS00001001418

• Integrative genomic and transcriptomic analysis of adult leiomyosarcoma (HIPO-028, HIPO-018, HIPO-021)

  Leiomyosarcoma (LMS) is an aggressive mesenchmyal malignancy with few therapeutic options. The mechanisms underlying LMS development, including clinically actionable genetic vulnerabilities, are largely unknown. We performed genomic and transcriptomic profiling of a large cohort of LMS tumors and identified substantial mutational heterogeneity, near-universal inactivation of TP53 and RB1, widespread DNA copy number alterations, chromothripsis, and frequent whole-genome duplication. Furthermore, we discovered recurrent alterations in telomere maintenance genes such as ATRX, RBL2, and RPA1, resulting in alternative lengthening of telomeres in 78% of cases. Finally, most tumors displayed hallmarks of “BRCAness”, including alterations in various homologous recombination DNA repair genes, multiple structural rearrangements, and enrichment of specific mutational signatures, and cultured LMS cells were sensitive towards olaparib and cisplatin treatment. This first comprehensive study of genetic alterations in LMS has uncovered key biological features that may inform future experimental research and enable the design of novel therapeutic strategies for this disease.

  Study EGAS00001002437

• Clonal_expansion_of_mutated_cell_population_in_bladder_urothelium_

  1cm biospies of from patients undergoing bladder cystectomy will be collected. The underlying muscle and stroma will be removed and the remaining epithelia dissected into small sequential areas which will be sent for ultra-deep exome sequencing using a panel of known cancer and viral genes. Sequence analysis using similar methods to Martincorena I et al (Science 2015, 348:880) will provide an idea of the somatic mutational landscape in these patient samples. Individual patient muscle samples will also be sequenced as a reference.

  Study EGAS00001001687

• Successful BRAF/MEK-inhibition in a young patient with BRAF V600E-mutated extrapancreatic acinar cell carcinoma (HIPO-021)

  Pancreatic acinar cell carcinoma (PAC) is a rare disease with a poor prognosis. Treatment options for metastatic PAC are limited and often follow chemotherapeutic regimens for pancreatic ductal adenocarcinoma. Although recurrent genomic alterations, such as BRAF fusions and defects in genes involved in homologous recombination DNA repair, have been described in PAC, data on the clinical efficacy of molecularly guided, targeted treatment are scarce. Here we describe the case of a 27-yr-old patient with BRAF V600E-mutated PAC who was successfully treated with a combination of BRAF and MEK inhibitors. The patient presented to our clinic with abdominal pain and weight loss. Imaging showed extensive retroperitoneal disease as well as mediastinal lymphadenopathy. Because of elevated alpha-fetoprotein (AFP) levels and inconclusive histologic findings, a germ cell tumor was suspected; however, PEI chemotherapy was unsuccessful. A repeat biopsy yielded the diagnosis of PAC and treatment with FOLFIRINOX was initiated. Comprehensive molecular profiling within the MASTER (Molecularly Aided Stratification for Tumor Eradication Research) precision oncology program revealed a somatic BRAF V600E mutation and a germline PALB2 stop-gain mutation. Therapy was therefore switched to BRAF/MEK inhibition, resulting in almost complete remission and disease control for 12 mo and a remarkable improvement in the patient's general condition. These results indicate that BRAF alterations are a valid therapeutic target in PAC that should be routinely assessed in this patient population.

  Study EGAS00001004282

• Melanoma_C32_ENU_Resistance_to_Single_Agent_Therapy

  This study involves mutagenizing C32, a melanoma cell line, with ENU to identify those mutations which engender resistance to a targeted treatment.

  Study EGAS00001001697

• Linking genes, genomic instability and molecular subgroups in medulloblastoma

  Brain tumors are the second most common pediatric cancer and carry the highest mortality rates in this age group. Medulloblastoma is the most frequent malignant brain tumor of childhood. Recent studies indicate that medulloblastoma comprises at least four sub-entities (SHH-signaling, WNT-signaling, Group-C, Group-D) that differ in molecular alterations, cell of origin, clinicopathological features and outcome. Further characterization of the entire spectrum of genomic alterations underlying the formation of these distinct groups is urgently needed to identify diagnostic and prognostic biomarkers for clinical management and uncover novel therapeutic targets.

  Study EGAS00001000085

• H3K27ac and RNA-seq data of neuroblastoma PDXs and/or primary tumors

  This study includes H3K27ac ChIP-seq and RNA-seq data of 6 neuroblastoma PDXs. It also contains RNA-seq data of 3 pairs of neuroblastoma tumors obtained at diagnosis and relapse. The MAP-GR-B25-NB-1 PDX was derived from the relapse of pair 1.

  Study EGAS00001002505

• 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

• Somatic_Variation_Angiosarcoma

  Through whole genome sequencing, this study will explore the mutational profiles and signatures within an angiosarcoma tumour from a patient with xeroderma pimentosum. Very little information is known about this tumour type and it has not previously been studied within the context of xerogerma pigmentosum.

  Study EGAS00001002610

• Myeloma_Follow_up_Pilot

  Targeted capture of exonic and intronic regions of interest for the study of genomic alterations in multiple myeloma.

  Study EGAS00001000743