5628 results for "*oma"

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• Molecular Attributes Underlying Central Nervous System and Systemic Relapse in Diffuse Large B-cell Lymphoma

  Central nervous system (CNS) relapse in diffuse large B-cell lymphoma remains a significant conundrum. While clinical risk scores and biomarkers allow the identification of patients with higher risk of CNS relapse, their predictive ability is low. Herein, we report findings from a comprehensive study examining gene expression changes, mutations and clonal evolution. Firstly, considering diagnostic samples from patients with CNS relapse, systemic relapse or no relapse, we found a striking enrichment of gene expression changes reflecting protein biosynthesis in patients who experienced CNS or systemic relapse. Furthermore, diagnostic specimens of relapsing cases were characterized by low immune infiltrates. The most discriminative gene feature in our analysis was SLAMF1, high expression of which was associated with favourable outcomes. Next, we assessed whether specific gene mutations were associated with subsequent CNS or systemic relapse. Activated B-cell-like genes such as PIM1, CD79B and PRDM1 were more frequently mutated in cases with CNS relapse, whereas TP53, BCL2 and FOXO1 mutations were associated with systemic relapse. Lastly, we performed tumor evolution analysis in five patients, identifying significant clonal divergence that accompanied CNS relapse. In summary, we identified both common biology underlying both CNS and systemic relapse, independent of cell-of-origin (COO), and specific COO-enriched gene mutations that conferred a higher risk of either CNS or systemic relapse. Moreover, we identified a pattern of clonal evolution that can explain difficulties in both predicting and treating CNS relapse.

  Study EGAS00001004057

• Molecular and Clonal Evolution in Recurrent Metastatic Gliosarcoma

  We present a rare case of a 37-year-old woman who was initially diagnosed with IDH wild-type gliosarcoma in the frontal lobe and later developed two local recurrences and extracranial metastases to the vertebral and pelvic bones. In order to understand the clonal relationships between the four tumor instances and the origin of metastasis, we performed whole genome sequencing of the intracranial tumors and the tumor located in the right iliac bone. Mutational and copy number profile comparisons of the metastatic to intracranial tumors highlighted a high similarity in molecular profile, but contrasting evidence regarding the origin of the metastasis. Subclonal reconstruction suggested a parallel evolution of the recurrent tumors, and that the metastatic tumor was largely derived from the first recurrence. We conclude that metastasis in glioma can be a late event in tumorigenesis.

  Study EGAS00001004076

• glioblastoma and glioblastoma stem cells (GSCs), RNA-seq and WGS

  Characterization of glioblastoma tumors and glioblastoma stem cells (GSCs) lines via RNA-seq and/or WGS profiling.

  Study EGAS00001004395

• Molecular profiling of EBV associated diffuse large B-cell lymphoma

  We describe distinct molecular mechanisms leading to recurrent activation of JAK-STAT signaling, perturbation of epigenetic regulators as well as other direct targetable alterations such as PD-L1 amplification and overexpression contributing to immune evasion of lymphoma cells. Using the LymphGen 2.0 classifier, we combine data of recurrent mutations, somatic copy number alterations, and structural variants in an integrative analysis . For the first time, we reveal that less than 20% of primary EBV+ DLBCLs can be attributed to established molecular clusters of DLBCL NOS emphasizing the unique molecular character of this disease.

  Study EGAS00001006400

• 71 Whole-exome sequencing of Esophageal Squamous Cell Carcinoma on Chinese Patients

  Esophageal Squamous Cell Carcinoma (ESCC) is one of the deadliest cancers worldwide. We performed 71 Whole-exome sequencing of Esophageal Squamous Cell Carcinoma on Chinese Patients.

  Study EGAS00001001475

• Somatic mutations predict an aggressive phenotype in meningioma but do not drive grade progression

  A subset of meningiomas progress in histopathological grade and drivers of progression are poorly understood. We aimed to identify somatic mutations and copy number alterations (CNAs) associated with grade progression in a unique matched tumour dataset. Utilising a prospective database, we identified 10 patients with meningiomas that had undergone grade progression and for whom matched pre- and post-progression tissue (n=50 samples) was available for targeted next-generation sequencing. Mutations in NF2 were identified in 4/10 patients, 94% were non-skull base tumours. In one patient, three different NF2 mutations were identified in four tumours. NF2 mutated tumours showed large scale CNAs, with highly recurrent losses in 1p, 10, 22q, and frequent CNAs on chromosomes 2, 3 and 4. There was a correlation between grade and CNAs in a subset of patients. In two patients with sphenoid wing Grade III tumours without detected NF2 mutations, a STAT6-NAB2 inversion was identified. Two patients with tumours without detected NF2 mutations showed a combination of loss and high gain on chromosome 17q. Mutations in SETD2, TP53, TERT promoter and NF2 were not uniform across recurrent tumours and did not correspond with grade progression. Meningiomas that progress in grade generally have a mutational profile already detectable in the pre-progressed tumour, suggesting an aggressive phenotype . CNA profiling shows frequent alterations in NF2 mutated tumours compared to non NF2 mutated tumours and the pattern of CNAs may be associated with grade progression in a subset of cases.

  Study EGAS00001006585

• Angiosarcoma_targeted_pulldown_cancer_gene_panel

  Extension of angiosarcoma whole genome sequencing study

  Study EGAS00001000589

• NIBIT-M4 Clinical Trial samples

  Patients (N=14) with unresectable stage III/IV melanoma received escalating doses of guadecitabine 30, 45, or 60 mg/m2/day subcutaneously on days 1 to 5 every 3 weeks, and ipilimumab 3 mg/kg intravenously on day 1 every 3 weeks, starting 1 week after guadecitabine, for four cycles. Patient-wise genome-wide DNA methylation, Whole Exome and RNA sequencing were then performed for samples obtained by surgical removal or fine-needle biopsy at baseline (W0), week 4 (W4) and week 12 (W12) after treatment. For Whole Exome Sequencing profiling, normal matched skin tissue was available only for the first eight patients.

  Study EGAS00001006736

• Multiomic profiling of early-passage melanoma cell lines.

  This study utilises multiomic profiling of early-passage melanoma cell lines to explore the interactions between distinct modalities of molecular regulation influencing melanoma cellular phenotype.

  Study EGAS00001004536

• 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