12155 results for "cancer rna-seq"

in 15.44 milliseconds.

• APOBEC Mutagenesis, Kataegis, Chromothripsis in EGFR-Mutant Osimertinib-Resistant Lung Adenocarcinomas

  Expanding on studies investigating apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like (APOBEC) mutagenesis in histological transformation of epidermal growth factor receptor (EGFR)-mutant lung cancers, it has been hypothesized that mutational signature analysis may help better understand acquired resistance to targeted therapies. Using mutational signature analysis in Receptor Tyrosine Kinase (RTK) driven lung adenocarcinomas, more specifically EGFR mutant lung cancer, APOBEC dominant mutational signatures were noted more frequently in subclonal post Tyrosine Kinase Inhibitor (TKI) treatment biospecimen samples and in the presence of large-scale genomic rearrangements. This is hypothesized to be due to the pressure of treatment with TKIs; a fact that should be further explored and can be potentially manipulated in order to overcome drug resistance.

  Study phs003812

• Longitudinal analysis of bone marrow heterogeneity reveals the co-evolution of malignant B cells and their T-cell niche supporting follicular lymphoma persistence

  Follicular Lymphoma (FL) is an indolent lymphoid malignancy characterized by cycles of remission and relapse, reflecting the inability of current therapies to fully eradicate tumor cells. Our hypothesis is that rare cancer precursor/persister cells (CPCs) evade treatment by homing to a protective tumor microenvironment, particularly within the bone marrow (BM), and/or by adopting specific cellular states, and form a rare reservoir of residual cells seeding lymphoma recurrence. To adress this, we collected paired BM samples at diagnosis and one year post-therapy from a clinical trial (FLIRT trial, NCT02303119) and applied multi-modal single-cell analysis to dissect the transcriptomics determinants of rare drug-tolerant persister cells and their surrounding T-cell niche.

  Study EGAS50000001295

• Development of Novel Chondrosarcoma Organoid Models for Drug Discovery

  Chondrosarcoma is a rare and aggressive malignant bone tumor characterized by resistance to conventional chemotherapy and radiotherapy. Its pathogenesis remains poorly understood, although recurrent mutations such as IDH1 have been implicated in tumor development. We treated patients with chondrosarcoma at the Osaka International Cancer Institute and established two organoid cultures from resected tumor specimens using a modified air-liquid interface method. After serial passaging, the organoids were successfully xenografted into NOD-scid IL2Rgnull (NSG) mice. The established organoids retained key histological features and genetic characteristics of the original tumors. These organoid models provide a novel and reliable platform for studying the biology of chondrosarcoma and may facilitate the development of effective therapeutic strategies for this treatment-resistant tumor.

  Study JGAS000834

• Whole-exome sequencing identifies new pathogenic germline variants in patients with colorectal polyposis

  Adenomatous polyposis confers an increased risk of colorectal cancer development. Here, we investigated probably underlying predisposition variants in patients with suspected colorectal polyposis without variants in APC and MUTYH genes by whole exome sequencing (WES). Twenty-seven patients were included and subjected to germline WES. After filtering out variants for sequencing quality, variant allele fraction frequency, and population frequency, variants were manually prioritized by the ACMG criteria. Among the variants identified, 17 were classified as pathogenic or likely pathogenic (in 12 patients). This study gives information of probably associated polyposis variants in Brazilian patients without germline pathogenic variants in APC and MUTYH genes, supporting the utilization of next-generation sequencing for screening in these patients beyond these genes.

  Study EGAS50000000591

• Mutational_landscape_in_haemochromatosis__WGS_

  Somatic mutation has recently been shown to play a role in disease other than cancer. Driver mutations associated with lipid metabolism and insulin pathway have been identified in non-alcoholic fatty liver disease (NAFLD). It is plausible that driver mutations seen in NAFLD are a consequence of selection pressure exerted on hepatocytes in the context of excess fat accumulation. It has not been investigated whether selection pressure and driver landscape varies between chronic liver diseases of different aetiologies. This study aims to investigate mutational landscape in haemochromatosis, which is a disorder caused by a build-up of iron in the liver. We aim to use data generated by whole-genome sequencing of laser-dissected microbiopsies from diseased livers to characterize driver landscape and mutational signatures in haemochromatosis patients.

  Study EGAS00001005157

• Genome-wide analysis of HPV integration in human cancers reveals recurrent, focal genomic instability

  Genomic instability is a hallmark of human cancers, including the 5% caused by human papillomavirus (HPV). Here we report a striking association between HPV integration and adjacent host genomic structural variation in human cancer cell lines and primary tumors. Whole genome sequencing revealed HPV integrants flanking and bridging extensive host genomic amplifications and rearrangements, including deletions, inversions and chromosomal translocations. We present a model of ³looping² by which HPV integrant-mediated DNA replication and recombination may result in viral-host DNA concatemers, frequently disrupting genes involved in oncogenesis and amplifying HPV oncogenes E6 and E7. Our high-resolution results shed new light on a catastrophic process, distinct from chromothripsis and other mutational processes, by which HPV directly promotes genomic instability.

  Study EGAS00001000599

• Targeting PTPRK-RSPO3 colon tumours promotesdifferentiation and loss of stem-cell function

  Colorectal cancer remains a major unmet medical need, promptinglarge-scale genomics efforts in the field to identify moleculardrivers for which targeted therapies might be developed. Wepreviously reported the identification of recurrent translocationsin R-spondin proteins present in a subset of colorectal tumours.Here we show that targeting RSPO3 in PTPRK-RSPO3-fusion positivehuman tumour xenografts inhibits tumour growth andpromotes differentiation. Notably, genes expressed in the stem-cellcompartment of the intestine were among those most sensitive toanti-RSPO3 treatment. This observation, combined with functionalassays, suggests that a stem-cell compartment drives PTPRK-RSPO3colorectal tumour growth and indicates that the therapeutictargeting of stem-cell properties within tumours may be a clinicallyrelevant approach for the treatment of colorectal tumors.

  Study EGAS00001001462

• Understanding_the_multicellular_dynamics_of_clear_cell_renal_cell_carcinoma___DNA_sequencing

  This study will reconstruct the single cellular phylogeny of tumour and immune cells in relation to both genomic, functional, and spatial location. 20 tumours in total will be studied, including non-progressing small renal masses, progressing small renal masses, relatively indolent larger tumours, and high risk tumour with metastatic sampling. We aim to: Generate a focused, comprehensive phylogenetic characterisation of tumour cells Understand the dependencies of the cancer genome, transcriptome, tissue architecture and the single cellular micro-environment Quantify the single cellular composition and functional intra- and inter- tumoural heterogeneity Determine the phylogeny of tumour associated lymphocytes and their relationship to neo-epitopes and the immune microenvironment Investigate the mechanisms by which the tumour-normal interface constrains tumoural growth

  Study EGAS00001003517

• Understanding_the_multicellular_dynamics_of_clear_cell_renal_cell_carcinoma___single_cell_RNA_sequencing

  This study will reconstruct the single cellular phylogeny of tumour and immune cells in relation to both genomic, functional, and spatial location. 20 tumours in total will be studied, including non-progressing small renal masses, progressing small renal masses, relatively indolent larger tumours, and high risk tumour with metastatic sampling. We aim to: Generate a focused, comprehensive phylogenetic characterisation of tumour cells Understand the dependencies of the cancer genome, transcriptome, tissue architecture and the single cellular micro-environment Quantify the single cellular composition and functional intra- and inter- tumoural heterogeneity Determine the phylogeny of tumour associated lymphocytes and their relationship to neo-epitopes and the immune microenvironment Investigate the mechanisms by which the tumour-normal interface constrains tumoural growth

  Study EGAS00001003519

• Genomic characterization of esophageal squamous cell carcinoma reveals critical genes underlying tumorigenesis and poor prognosis

  The genetic mechanisms underlying the poor prognosis of esophageal squamous cell carcinoma (ESCC) are not well understood. In this study, we comprehensively characterized somatic mutations, copy number alterations (SCNAs)/structural variants (SVs) found in ESCC from sequencing 10 whole-genome and 57 whole-exome matched tumor-normal pairs. We identified multiple somatic mutations seen previously in known cancer pathways and identified candidate genes for ESCC including VANGL1 and MIR4707. A survival analysis based on the expression profiles of 321 ESCC individuals indicated that the somatically altered genes we found were significantly associated with ESCC poorer survival. Subsequently, we performed functional studies to validate the roles of the altered genes in tumor proliferation and metastasis.

  Study EGAS00001001723