5706 results for "canc*"

in 43.77 milliseconds.

• Infant Glioma Molecular Subtype

  Infant gliomas have completely different clinical behavior than gliomas in children and adults. Low-grade tumors are more aggressive with a higher mortality rate, while high-grade tumors are more benign. However, we have little understanding of their biology and so cannot explain this behavior and what constitutes optimal clinical management. To solve this enigma, we performed a comprehensive genetic analysis of the largest cohort to date of infantile gliomas. We uncovered several important findings which dramatically change the management of these cancers. Infant hemispheric gliomas harbor unique alterations in ROS, ALK, MET and other genes found in adult carcinomas. Unlike in adults, they are typically the only alteration present and some of these tumors regress from high- to low-grade partially explaining their favorable clinical outcome. Midline gliomas harbor RAS/MAPK pathway mutations, progress rapidly, and do not respond to current chemoradiation approaches, partially explaining their poorer outcome. These data suggest that infant gliomas require different therapeutic approaches including early use of targeted therapies.

  Study EGAS00001003714

• DNA Methylation loss coupled with mitotic cell division promotes immune evasion of tumours with high mutation load

  Mitotic cell division increases tumour mutation burden and copy number load with a positive and inverse correlation, respectively, with the clinical benefit of immunotherapy. Markers of cell division correlate also with genomic demethylation involving methylation loss in late-replicating partial methylation domains. Here we find that immunomodulatory pathway genes are concentrated in these domains and transcriptionally repressed in demethylated tumours with CpG island promoter hypermethylation. Global methylation loss correlated with immune evasion signatures independently of mutation burden and aneuploidy. Methylome data of our cohort (n = 60) and a published cohort (n = 81) in lung cancer and a melanoma cohort (n = 40) consistently demonstrated that genomic methylation alterations counteract the contribution of high mutation burden and increase immunotherapeutic resistance. Higher predictive power was observed for methylation loss than mutation burden. We also found that genomic hypomethylation correlates with the immune escape signatures of aneuploid tumours. Hence, DNA methylation alterations implicate epigenetic modulation as a combination regimens for precision immunotherapy.

  Study EGAS00001003731

• Measuring minimal residual disease in acute myeloid leukemia with MASQ

  Study EGAS00001003732

• IBD-dysplasia

  Study EGAS00001003767

• Dual-mTOR inhibitor Rapalink-1 reduces prostate cancer patient-derived xenograft growth and alters tumor heterogeneity

  Bone metastasis is the leading cause of prostate cancer (PCa) mortality, frequently marking the progression to castration-resistant PCa. In this study, we compared the molecular pathways enriched in a set of bone metastasis from breast and prostate cancer from snap-frozen tissue. To further model PCa drug resistance mechanisms, we used two patient-derived xenografts (PDX) models of bone-metastatic PCa, BM18 and LAPC9.

  Study EGAS00001004431

• Landscape and significance of multiple mutations in oncogenes.

  This study is a comprehensive pan-cancer study of oncogenic multiple mutations (MMs) which includes long-read whole-genome sequencing data (n = 3).

  Study EGAS00001003763

• WXS of 147 lung cancer patients treated with immunotherapy

  We first attempted to predict MHC-binding neoantigens at high accuracy with convolutional neural networks. This prediction model outperformed previous methods in > 70% of test cases. Importantly, our method remarkably increased the predictive value of neoantigen load especially in combination with known resistance parameters. We then developed a classifier that can predict resistance from point mutations that are deleterious to protein function. Notably, genes involved in the adaptive immune response, cytokine signaling,and EGFR signaling held high explanatory power. Furthermore, when integrated with our neoantigen profiling, these anti-immunogenic mutations revealed significantly higher predictive power than known resistance factors.

  Study EGAS00001003781

• Polyomavirus-positive Merkel cell carcinoma derived from a trichoblastoma suggests an epithelial origin of Merkel cell carcinoma

  Study EGAS00001003784

• Patient-Derived Lung Cancer Organoid

  Lung cancer shows substantial genetic and phenotypic heterogeneity across individuals, driving a need for personalized medicine. Here we report lung cancer organoids and normal bronchial organoids established from patients tissues comprising five histological subtypes of lung cancer and non-neoplastic bronchial mucosa as in vitro models representing individual patient. The lung cancer organoids recapitulate the tissue architecture of the primary lung tumours and maintain the genomic alterations of the original tumours during long-term expansion in vitro. The normal bronchial organoids maintain cellular components of normal bronchial mucosa. Lung cancer organoids respond to drugs based on their genomic alterations: a BRCA2 mutant organoid to olaparib, an EGFR mutant organoid to erlotinib, and an EGFR mutant/MET amplified organoid to crizotinib. Considering the short length of time from organoid establishment to drug testing, our newly developed model may prove useful for predicting patient-specific drug responses through in vitro patient-specific drug trials.

  Study EGAS00001003786

• Molecular profiling reclassifies adult astroblastoma into known and clinically distinct tumor entities with frequent MAPK pathway alterations

  Study EGAS00001003798

• Cell-free DNA analysis reveals POLR1D-mediated resistance to bevacizumab in colorectal cancer

  Bevacizumab is an approved anti-angiogenic drug for patients with metastasized colorectal cancer (mCRC) targeting VEGF. The survival benefit of anti-VEGF therapy in mCRC patients is limited to a few months and acquired resistance mechanisms are greatly unknown. Using plasma DNA, we studied the evolution of tumor genomes in a cohort of patients with mCRC (n=150) and observed a recurrent focal amplification (8.7% of cases) on chromosome 13q12.2. Analysis of TCGA data (n=619) suggested an association with later stages, which we confirmed by longitudinal plasma analyses. We defined the minimally amplified region and studied the mechanistic consequences of copy number gain of the involved genes. The amplification of one gene, POLR1D, impacted cell proliferation, resulting in upregulation of VEGFA, an important regulator of angiogenesis which has been implicated in the resistance to bevacizumab. In several patients, we observed the emergence of this 13q12.2 amplicon under bevacizumab treatment, which was invariably associated with evolution of therapy resistance. Hence, we describe a novel resistance mechanism against a widely applied treatment in mCRC patients which will impact clinical management

  Study EGAS00001003791

• Whole-exome sequencing of Fanconi anemia-like inherited bone marrow failure syndrome

  We identified three fibroblast cultures derived from aplastic anemia patients in the Japanese Cancer Research Resources Bank (JCRB) Cell Bank that showed high levels of sister chromatid exchanges (SCEs) in PHA-stimulated lymphoblasts. To elucidate the genetic basis of the high SCE, we carried out whole exome sequencing of these samples. Subsequently, germline variants were analysed for these patients.

  Study EGAS00001003809

• Epigenomics and Single-cell Sequencing Define a Developmental Hierarchy in Langerhans Cell Histiocytosis

  Langerhans cell histiocytosis (LCH) is a rare neoplasm predominantly affecting children. It occupies a hybrid position between cancers and inflammatory diseases, and it provides an attractive model for studying cancer development. To explore the molecular mechanisms underlying the pathophysiology of LCH and its characteristic clinical heterogeneity, we investigated the transcriptomic and epigenomic diversity in primary LCH lesions. Using single-cell RNA sequencing, we identified multiple recurrent types of LCH cells within these biopsies, including putative LCH progenitor cells and several subsets of differentiated LCH cells. We confirmed the presence of proliferative LCH cells in all analysed biopsies using immunohistochemistry, and we defined an epigenomic and gene-regulatory basis of the different LCH cell subsets by chromatin accessibility profiling. In summary, our single-cell analysis of LCH uncovered an unexpected degree of cellular, transcriptomic, and epigenomic heterogeneity among LCH cells, indicative of complex developmental hierarchies in LCH lesions.

  Study EGAS00001003822

• Immunopeptidomics of colorectal cancer organoids reveals a sparse HLA class I neoantigen landscape and no increase in neoantigens with interferon or MEK-inhibitor treatment

  Study EGAS00001003886

• Multimodal Genomic Features Predict Outcome of Immune Checkpoint Blockade in Non-small Cell Lung Cancer

  Despite progress in immunotherapy, identifying patients that respond has remained a challenge. Through analysis of whole-exome and targeted sequence data from 5,449 tumors, we found a significant correlation between tumor mutation burden (TMB) and tumor purity, suggesting that low tumor purity tumors are likely to have inaccurate TMB estimates. We developed a new method to estimate a corrected TMB (cTMB) that was adjusted for tumor purity and more accurately predicted outcome to immune checkpoint blockade (ICB). To identify improved predictive markers together with cTMB, we performed whole-exome sequencing for 104 lung tumors treated with ICB. Through comprehensive analyses of sequence and structural alterations, we discovered a significant enrichment in activating mutations in receptor tyrosine kinase (RTK) genes in non-responding tumors in three immunotherapy-treated cohorts. An integrated multivariable model incorporating cTMB, RTK mutations, smoking-related mutational signature, and HLA status provided an improved predictor of response to immunotherapy that was independently validated.

  Study EGAS00001003892

• Identification of hypermutation and defective mismatch repair in ctDNA from metastatic prostate cancer

  DNA mismatch repair defects (MMRd) and tumor hypermutation are rare and under-characterized in metastatic prostate cancer. Furthermore, since hypermutated MMRd prostate cancers can respond to immune checkpoint inhibitors, there is an urgent need for practical detection tools. We analyzed cell-free DNA targeted sequencing data from 434 metastatic prostate cancer patients with circulating tumor DNA (ctDNA) purity above 2%. Samples with somatic hypermutation were subjected to 150x whole exome sequencing. These data allowed us to interrogate the salient genomic properties of this rare prostate cancer subtype and correlate findings with patient clinical outcomes.

  Study EGAS00001003899