14970 results for "cancer studies using rna-seq"

in 18.68 milliseconds.

• Identification of neoantigen from MSI-CRC patient derived organoids and its application for targeting by autologous T cells

  Targeting neoantigens expressed only by tumor cells enable tumor destruction without unexpected damages to healthy tissues. Here, we identified neoantigens from microsatellite instable (MSI) colorectal cancer (CRC) patient-derived organoids by genomics and immunopeptidomics approches. The neoantigens in this study were predicted from frame-shift mutation by whole-genome sequencing and confirmed its presentation on organoids surface class I HLA molecules by mass spectrometry. We utilized these neoantigens to isolate neoantigen-specific CD8 T cells from autologous PBMC, and proved tumor organoids killing ability of the CD8 T cells, whereas it did not attack normal organoids. This study provides a platform to identify neoantigen from patient-derived cancer organoids and a model to validate T cell recognition, which could be useful for adoptive CD8 T cell transfer treatment for MSI-CRC patient.

  Study EGAS00001006633

• Convergent evolution towards CD38 biallelic loss is a recurrent mechanism of resistance to anti-CD38 antibodies in multiple myeloma.

  Monoclonal antibodies directed against CD38 are a therapeutic mainstay in multiple myeloma (MM). While they have contributed to improved outcomes, most patients will still experience disease relapse. Despite their ubiquity, little is known about tumor-intrinsic mechanisms of resistance to these drugs. Antigen escape, whereby tumor cells alter expression of cell surface immunotherapy targets, has been proposed as a potential avenue, and has been seen with other immunotherapies in MM. Yet, it is unknown whether MM cells can develop permanent resistance to anti-CD38 antibodies by acquiring genomic events leading to biallelic disruption of the CD38 gene locus. Here, by using whole genome and whole exome sequencing data from 701 newly diagnosed patients, 72 patients at relapse with naivety to anti-CD38 antibodies, and 52 patients collected at relapse following anti-CD38 antibodies, we report biallelic inactivation of CD38 as a recurrent mechanism of resistance in 6% of patients, often via convergent evolution where distinct subclones are advantaged towards the same selective endpoint within the same patient. Monoallelic loss of the CD38 locus was seen in another 14% post-CD38-directed therapy. Three of the cases with biallelic events on CD38 presented with missense mutations and retained CD38 expression. Functional work demonstrated that two of these mutations decreased binding affinity and antibody-dependent cellular cytotoxicity of commercial antibodies Daratumumab and Isatuximab. However, the third mutation (R140G) provided relative resistance only towards one commercial product. Given that patients are often rechallenged with CD38 antibodies following disease progression, these data support the need for next generation sequencing to guide treatment selection.

  Study EGAS50000000709

• Biomarker Screen for Efficacy of Oncolytic Virotherapy in Patient-derived Pancreatic Cancer Cultures

  Pancreatic ductal adenocarcinoma (PDAC) is a tumour entity with unmet medical need. To assess the therapeutic potential of oncolytic virotherapy (OVT) against PDAC, different oncolytic viruses (OVs) are currently investigated in clinical trials. However, systematic comparisons of these different OVs in terms of efficacy against PDAC and biomarkers predicting therapeutic response are lacking. We screened fourteen patient-derived PDAC cultures for their sensitivity to five clinically relevant OVs, namely serotype 5 adenovirus Ad5-hTERT, herpes virus T-VEC, measles vaccine strain MV-NIS, reovirus jin-3, and protoparvovirus H 1PV using live cell analysis, quantification of viral genome/gene expression, cell viability as well as cytotoxicity assays. Sensitivity was correlated with transcriptome profiles to identify potential predictive biomarkers for response to OVT. Patient-derived PDAC cultures showed individual response patterns to OV treatment. Twelve of fourteen cultures were responsive to at least one OV, with no single OV proving superior or inferior across all cultures. Known host factors for distinct viruses were retrieved as potential biomarkers. Compared to the basal-like molecular subtype, the quasi-mesenchymal subtype of PDAC was more sensitive to H-1PV, jin-3, and T-VEC. Expression of viral entry receptors did not correlate with sensitivity to OV treatment. Rather, cellular pathways controlling immunological, metabolic, and proliferative signalling appeared to determine outcome. For instance, high baseline expression of interferon-stimulated genes (ISGs) correlated with relative resistance to oncolytic measles virus, whereas cGAS expression was associated with exceptional response. Combination treatment of MV-NIS with a cGAS inhibitor improved tumour cell killing in several PDAC cultures.

  Study EGAS00001007001

• Reference epigenomes generated as part of the International Human Epigenomics Consortium (IHEC)

  The Centre for Epigenome Mapping Technologies (CEMT) is an epigenome sequencing platform funded by the Canadian Institutes of Health Research (CIHR) and Genome BC as part of the Canadian Epigenetics, Environment and Health Research Consortium (CEEHRC). CEMT aims to produce 100 human reference epigenomes, each comprising the following datasets: whole genome; whole genome bisulfite and oxidative bisulfite; transcriptome; microRNA; and chromatin immunoprecipitation (ChIP)-seq for the core chromatin marks (H3K4me1, H3K4me3, H3K9me3, H3K27me3, H3K36me3, and H3K27ac).CEEHRC is a full member of the International Human Epigenomics Consortium (IHEC), which aims to coordinate the production of 1,000 reference maps of human epigenomes for key cellular states relevant to health and diseases. As such, all datasets submitted by the CEMT platform conform to IHEC assay standards and metadata guidelines.

  Study EGAS00001000552

• A cycling, progenitor-like cell population at the root of atypical teratoid rhabdoid tumor subtype differentiation trajectories.

  Background: Atypical teratoid rhabdoid tumors (ATRTs), characterized by the loss of SMARCB1, are among the most lethal pediatric central nervous system (CNS) tumors. Three molecular subtypes have been identified, each defined by distinct molecular and clinical features. No subtype-specific treatments are available, highlighting the necessity to better understand inter- and intra-subtype heterogeneity. Methods: We generated a single-nucleus transcriptome atlas of ATRTs, validated by single-cell ATAC-seq and spatial transcriptomics, to study subtype-specific differentiation trajectories. Results: We identified brain progenitor-like expression profiles within unique subtype-specific differentiation lineages. A shared cycling, progenitor-like cell population, interspersed throughout tumors, was observed across all ATRT samples. Moreover, we demonstrate that subtype-specific differentiation trajectories can be induced pharmacologically in ATRT tumoroids directing tumor cells towards a non-proliferative, mature phenotype. Conclusions: Our study reveals that ATRT subtypes exhibit signaling trajectories mirroring normal fetal brain development, enabling the development of maturation therapies tailored towards ATRTs.

  Study EGAS00001008108

• Novel driver variants in the histone 3.3 genes, H3F3A and H3F3B, define bone and cartilage cancer sub-types

  A selection of human cancers harbours somatic driver mutations in genes encoding histones, most notably childhood brain tumours with K27M substitutions of the histone 3.3 gene, H3F3A. We performed whole genome sequencing of the benign cartilage tumour, chondroblastoma, and targeted sequencing of histone 3.3 genes, H3F3A and H3F3B, in seven further skeletal tumour types. We identified an exceptionally high prevalence of novel histone 3.3 driver mutations at glycine 34 and at lysine 36. Histone 3.3 gene mutations were found in 91% in giant cell tumours of bone (48/53), mainly H3F3A G34W variants, and in 92% of chondroblastoma (73/79), predominantly K36M mutations in H3F3B. H3F3B is paralogous to the cancer gene H3F3A. However, H3F3B driver variants have not previously been reported in human cancer. Our observation demonstrate remarkable tumour-specificity of mutations, with respect to which histone 3.3 gene and residue is mutated, indicating that the advantage these mutations confer is tumour dependent. Moreover, tumour-specific mutation of H3F3A and H3F3B suggests, that although both genes encode identical proteins, they are likely non-redundant and employed differentially during skeletal development.

  Dataset EGAD00001000646

• Genomic Characterization of Patient-Derived Xenograft Models to Improve Targeted Therapy for HER2+ Breast Cancer Brain Metastases Treatments

  We have developed orthotopic patient-derived xenograft models of HER2 positive breast cancer metastasized into the brain of patients to test novel therapeutic strategies. In this study, we identified a novel combinatorial therapeutic strategy that has resulted in a durable remission and markedly increased overall survival in majority of patient-derived xenograft (PDX) models tested. We performed whole exome sequencing analysis of these PDX tumors and their matched blood and patient samples to investigate drug sensitive and resistance mechanisms. Our sequencing data revealed an interesting association of genotyping and phenotyping with tumors responses to drug treatment.

  Study phs001063

• Multiregion Sequencing of Localized Prostate Cancer

  Ten patients with treatment-naïve, locally advanced or localized prostate cancer underwent radical prostatectomy. Pathological stage ranged from T2aN0 to T3bN1, and Gleason scores from 3+4 to 4+5. Tumor foci were mapped, and DNA was extracted from multiple (5-9) regions from a single, contiguous index focus. Whole exome sequencing was performed to identify single nucleotide variants and indels, and low coverage whole genome sequencing was performed to estimate copy number variation. Phylogenetic relationships between foci was determined, and alterations associated with advanced disease or response to targeted therapy were identified.

  Study phs001465

• Combined Targeting of CDK4/6 and HER2 Signaling in Orthotopic Patient-Derived Xenografts of HER2-Positive Breast Cancer Brain Metastases

  Patients with metastatic HER2-positive (HER2+) breast cancer will frequently develop brain metastases (BCBMs). Here, we report that p16INK4A, a tumor suppressor, is deficient in the majority of HER2+ BCBMs. Furthermore, p16INK4A deficiency, as measured by protein immunohistochemistry, can be a predictive marker associated with response to combined treatment with tucatinib and abemaciclib in our orthotopic patient-derived xenografts (PDXs) models of HER2+ BCBMs. Our findings provide the rationale for a biomarker-driven clinical trial of combined treatment with CDK4/6- and HER2-targeted agents for patients with HER2+ BCBM.  

  Study phs002482

• Tumor Infiltrating Lymphocytes (TIL) Recognize Unique Somatic Mutations and Mediate Objective Clinical Responses in Metastatic Breast Cancer

  The purpose of this study is to investigate the immunogenicity of tumor mutations in patients with metastatic cancer. Harvest and analysis of progressing metastatic lesions are used for generation of tumor infiltrating lymphocyte (TIL) cultures and the detections of somatic mutations. In vitro T cell activation assays are used to examine the immune recognition of tumor mutations by autologous TIL. Once a candidate is determined to have a cell product that meets the requirements of one of the Surgery Branch clinical trials, the candidate is evaluated for enrollment in a prospective adoptive cell therapy trial.

  Study phs002735

• ERBB2/HER2 alterations in ctDNA and metachronous tissues of patients with metastatic urothelial cancer - WGS

  Whole genome sequencing data related to the publication "ERBB2/HER2 alterations in ctDNA and metachronous tissues of patients with metastatic urothelial cancer." ERBB2 alterations, usually amplifications or activating mutations, are seen in up to 20% of urothelial carcinoma and can be targeted by monoclonal antibodies, small molecule inhibitors, and most recently, antibody-drug conjugates. Here, we perform targeted and whole-genome sequencing of cell-free DNA and archival FFPE of mUC with and without ERBB2 alterations to identify unique genomic and clinical features of ERBB2-altered cancers, accompanied by IHC, FISH, and detailed clinical outcomes.

  Study EGAS50000001082

• WES analysis of paired tumor and non-tumoral DNA of 4 patients with non-muscle-invasive bladder cancer

  We performed WES of tumor DNA and non-tumoral DNA (extracted from PBMC) of 4 patients with non-muscle invasive bladder cancer, who after the tumor resection went on to receive BCG treatment as they had high-risk disease. In order to identify tumor-specific mutations that could give rise to patient-specific neo-epitopes, we performed paired WES of tumor and non-tumoral DNA for each patient. For patient UC2, 3 different tumors were resected at the same time and DNA from these 3 tumors were sent separately for WES.

  Study EGAS50000001382

• Clinical validity of post-surgery circulating tumor DNA (ctDNA) in stage III colon cancer patients treated with adjuvant chemotherapy: the PROVENC3 study

  The PROVENC3 study aimed to determine the clinical validity of post-surgery ctDNA testing in patients with stage III colon cancer treated with adjuvant chemotherapy (ACT). Blood was collected pre-surgery, post-surgery and post-adjuvant chemotherapy. Tumor-informed plasma ctDNA detection was performed through integrated whole genome sequencing (WGS) analyses of formalin-fixed paraffin-embedded tumor tissue DNA (80x), white blood cell germline DNA (40x) and plasma cell-free DNA (30x). These raw WGS data for 209 patients are shared in .cram format in this EGA submission.

  Study EGAS50000000804

• Breast Cancer - Subtype defined by an amplification of the HER2 gene

  Clinically positive HER2 (cHER2+) breast cancers (BC) are defined by the amplification and overexpression of the human epidermal growth factor receptor (HER2/ERBB2) gene on chromosome region 17q12 and represent 15% of all BCs. Although anti-HER2 targeted therapies have improved BC’s natural history, the magnitude of their benefit varies widely between patients and deciphering the genomic heterogeneity of cHER2+ BC may provide a basis to better understand patients’ outcome. As part of the ICGC Breast Cancer Working Group effort, we combined whole genome sequencing and transcriptomic analyses of 64 cHER2+ primary invasive carcinomas.

  Study EGAS00001001431

• Structural rearrangements generate cell-specific, gene-independent CRISPR-Cas9 loss of fitness effects.

  CRISPR-Cas9 genome editing is widely used to study gene function, from basic biology to biomedical research. Structural rearrangements are a ubiquitous feature of cancer cells and their impact on the functional consequences of CRISPR-Cas9 gene-editing has not yet been assessed. Utilizing CRISPR-Cas9 knockout screens for 250 cancer cell lines, we demonstrate that targeting structurally rearranged regions, in particular tandem or interspersed amplifications, is highly detrimental to cellular fitness in a gene independent manner. In contrast, amplifications caused by whole chromosomal duplications have little to no impact on fitness. This effect is cell line specific and dependent on the ploidy status. We devise a copy-number ratio metric that substantially improves the detection of gene-independent cell fitness effects in CRISPR-Cas9 screens. Furthermore, we develop a computational tool, called Crispy, to account for these effects on a single sample basis and provide corrected gene fitness effects. Our analysis demonstrates the importance of structural rearrangements in mediating the effect of CRISPR-Cas9-induced DNA damage, with implications for the use of CRISPR-Cas9 gene-editing in cancer cells.

  Dataset EGAD00001004124