Search Results - EGA European Genome-Phenome Archive

Stromal-induced epithelial-mesenchymal transition induces drug resistance in acute lymphoblastic leukemia

Bone marrow (BM) microenvironment-induced drug resistance in acute lymphoblastic leukemia (ALL) is thought to be mediated by intercellular interaction of leukemic cells with BM niches, but the mechanistic basis of resistance is poorly understood. Here, we genomic and functional analyses, we show that ALL-BM mesenchymal stromal cells (MSC) interactions encompass direct cell-cell adhesion via integrin α4β1, uni-directional secretion of soluble factors from MSC to ALL, and bidirectional transfer of cellular vesicles through tunneling nanotubes. We show that this crosstalk drives an epithelial-mesenchymal transition (EMT)-like program in ALL cells adhering to MSC, thereby triggering stem cell-like features including drug resistance and survival advantage. Moreover, single-cell RNA sequencing of cell line and primary ALL samples identified a hybrid cell state derived from B-ALL adhered to MSC, that exhibits both B-ALL and MSC gene signatures that are orchestrated by an EMT-like program. Multiple EMT-activating pathways including WNT/β-catenin, cytokine/STAT3, TGFβ, NOTCH1, and NF-κB-dependent signaling pathways are activated in MSC-adherent ALL cells; however, only the inhibition of either WNT/β-catenin or cytokine/STAT3 pathway could attenuate the survival and drug resistance of ALL cells adherent to MSC. Notably, we identified that this hybrid cell state exhibited elevated WNT/β-catenin-mediated transcriptional activity. Finally, we show that blocking of the interaction of β-catenin and CBP interaction abrogates the survival and drug resistance of ALL cells adhered to MSC, indicating that targeting of an EMT-like program is potential therapeutic regimen in targeting cell extrinsically acquired drug resistance in ALL.

Study EGAS00001006120

Molecular and clinical diversity in primary central nervous system lymphoma: a LOC Network study

Primary central nervous system lymphoma (PCNSL) is a distinct extranodal lymphoma presenting with limited stage disease but variable response rates to treatment despite homogenous pathological presentation. The likely underlying molecular heterogeneity and its clinical impact is poorly understood. We performed a comprehensive genome-wide analysis of 147 PCNSL from fresh-frozen tumor tissue from immunocompetent, treatment naïve PCNSL patients, employing whole-exome sequencing, assessment of somatic copy number alterations and DNA methylation, and RNA expression. These data were integrated and correlated with the clinico-radiological characteristics and outcomes of the patients. We validated our results in an independent series of 93 PCNSL formalin-fixed, paraffin-embedded (FFPE) samples. Consensus clustering of multi-omics data identified four robust, non-overlapping, prognostically significant clusters (CS) within PCNSL. The CS1 group, characterized by high proliferation and Polycomb Repressive Complex 2 (PRC2) complex activity had an intermediate outcome between CS2/CS3 and CS4. Patients who had PCNSL with an “immune-hot” (CS4) profile had the most favorable clinical outcome. In contrast, patients with the immune-cold hypermethylated CS2 and the heterogenous-immune CS3 groups had a poor prognosis. Nearly all PCNSL patients with meningeal infiltration harbored HIST1H1E mutations, enriched in the CS3 group. The integrated analysis suggests that the CS4 group may be more susceptible to immunotherapy. The integration of genome-wide data from multi-omics data revealed four molecular patterns in PCNSL with a distinctive prognostic impact that significantly improved the current clinical stratification. This molecular classification using FFPE samples facilitates routine use in clinical practice and provides potential precision-medicine strategies in PCNSL.

Study EGAS00001006191

DNA methylation-based prognostic subtypes of chordoma tumors in tissue

Chordomas are rare malignant bone cancers of the skull-base and spine. Patient survival is variable and not reliably predicted using clinical factors or molecular features. This study identifies prognostic epigenetic chordoma subtypes that are detected noninvasively using plasma methylomes. Methylation profiles of 68 chordoma surgical samples were obtained between 1996 and 2018 across three international centers along with matched plasma methylomes where available. Consensus clustering identified two stable tissue clusters with a disease-specific survival difference that was independent of clinical factors in a multivariate Cox analysis (HR = 14.2, 95%CI: 2.1–94.8, P = 0.0063). Immune-related pathways with genes hypomethylated at promoters and increased immune cell abundance were observed in the poorperforming “Immune-infiltrated” subtype. Cell-to-cell interaction plus extracellular matrix pathway hypomethylation and higher tumor purity were observed in the better-performing “Cellular” subtype. The findings were validated in additional DNA methylation and RNA sequencing datasets as well as with immunohistochemical staining. Plasma methylomes distinguished chordomas from other clinical differential diagnoses by applying fifty chordoma-versusother binomial generalized linear models in random 20% testing sets (mean AUROC = 0.84, 95%CI: 0.52–1.00). Tissue-based and plasma-based methylation signals were highly correlated in both prognostic clusters. Additionally, leave-one-out models accurately classified all tumors into their correct cluster based on plasma methylation data. Here, we show the first identification of prognostic epigenetic chordoma subtypes and first use of plasma methylome based biomarkers to noninvasively diagnose and subtype chordomas. These results may transform patient management by allowing treatment aggressiveness to be balanced with patient risk according to prognosis.

Study EGAS00001006406

Multi-omic analysis of the tumor microenvironment shows clinical correlations in Ph1 study of atezolizumab +/- SoC in MM

Multiple myeloma (MM) remains incurable, and treatment of relapsed/refractory (R/R) disease is challenging. There is an unmet need for more targeted therapies in this setting; deep cellular and molecular phenotyping of the tumor and microenvironment in MM could help guide such therapies. This phase 1b study (NCT02431208) evaluated the safety and efficacy of the anti-programmed death-ligand 1 monoclonal antibody atezolizumab (Atezo) alone or in combination with the standard of care (SoC) treatments lenalidomide (Len) or pomalidomide (Pom) and/or daratumumab (Dara) in patients with R/R MM. Study endpoints included incidence of adverse events (AEs) and overall response rate (ORR). A novel unsupervised integrative multi-omic analysis was performed using RNA sequencing, mass cytometry immunophenotyping, and proteomic profiling of baseline and on-treatment bone marrow samples from patients receiving Atezo monotherapy or Atezo+Dara. A similarity network fusion (SNF) algorithm was applied to preprocessed data. Eighty-five patients were enrolled. Treatment-emergent deaths occurred in 2 patients; both deaths were considered unrelated to study treatment. ORRs ranged from 11.1% (Atezo+Len cohorts, n=18) to 83.3% (Atezo+Dara+Pom cohort, n=6). High-dimensional multi-omic profiling of the tumor microenvironment and integrative SNF analysis revealed novel correlations between cellular and molecular features of the tumor and immune microenvironment, patient selection criteria, and clinical outcome. Atezo monotherapy and SoC combinations were safe in this patient population and demonstrated some evidence of clinical efficacy. Integrative analysis of high dimensional genomics and immune data identified novel clinical correlations that may inform patient selection criteria and outcome assessment in future immunotherapy studies for myeloma.

Study EGAS00001007286

GeneScreen, a Population Based, Targeted Genomic Screening Study

The GeneScreen research study was based at the University of North Carolina (UNC) at Chapel Hill. It brought together researchers from different disciplines, including genetics, clinical medicine, bioethics, sociology, anthropology, psychology, and public health, to study the best ways to offer targeted genetic screening to the general adult population. DNA samples were collected from people who joined GeneScreen to look at a targeted panel of 17 genes. It tested for genetic differences (called mutations) that can cause one of 11 rare, but preventable or treatable conditions, including certain types of cancer and heart disease. Each condition has specific medical advice people can follow with their doctors to prevent or treat a serious health problem. The GeneScreen study was approved by the UNC Institutional Review Board and by the Kaiser Permanente Center for Health Research Institutional Review Board. GeneScreen is funded by the National Human Genome Research Institute of the National Institutes of Health.

Study phs001817

A Genome-wide Association Study (GWAS) of Risk for Osteosarcoma

This is a genome-wide association study (GWAS) of osteosarcoma, the most common primary bone malignancy. Osteosarcoma typically occurs in adolescents and young adults. It occurs at increased frequency in several inherited cancer predisposition syndromes but the genetic contribution to sporadic osteosarcoma is largely unexplored. The objective of this study was to identify genetic risk factors for osteosarcoma by conducting a genome-wide association study. We developed collaborations with multiple institutions in order to attain the necessary sample size required to discover novel loci in the genome associated with osteosarcoma using the GWAS approach. Genomic DNA (either blood or buccal in source) derived from osteosarcoma cases was obtained from each participating institution or research group. De-identified blood or buccal cell DNA samples from osteosarcoma cases were derived from existing biobanks at the collaborative institutions. Control subjects were derived from existing NCI cohorts and matched by gender and ethnicity.

Study phs000734

Metastatic Colorectal Adenocarcinoma Tumor Purity Assessment from Whole Exome Sequencing Data

As molecular medicine wields greater and greater influence on cancer patient care, including therapeutic selection, it becomes increasingly important to understand the power and deficiencies of computational tools used in decision making processes. Here we use a set of unselected metastatic colorectal tumor samples in a head-to-head comparison between the calculation of stromal content by a board certified pathologist, versus that derived from whole exome sequencing and purity assessment by a variety of common computational methods. We find that in about 1/2 of the samples the computational methods each do a poor job of assessing the percent stromal contamination, and as a result, tumor variant allele frequencies (VAFs) are low or undetected, whereas analysis of organoids derived from the same tumors yielded much higher VAFs in keeping with their lower stromal content. The whole exome sequence of our samples is available via dbGaP, accession phs003059.v1.p1.

Study phs003059

Structure of the Mucosal and Stool Microbiome in Lynch Syndrome

The gut microbiota has been associated with colorectal cancer (CRC), but causal alterations preceding CRC have not been elucidated. To prospectively assess microbiome changes prior to colorectal neoplasia, we investigated samples from 100 Lynch syndrome patients using 16S rRNA gene sequencing of colon biopsies, coupled with metagenomic and metatranscriptomic sequencing of feces. Colectomy and CRC history represented the largest effects on microbiome profiles. A subset of Clostridiaceae were depleted in stool corresponding with baseline adenomas, while Desulfovibrio was enriched in both stool and mucosal biopsies. A classifier leveraging stool metatranscriptomes resulted in modest power to predict interval development of preneoplastic colonic adenoma. Predictive transcripts corresponded with a shift in flagellin contributors and oxidative metabolic microenvironment, potentially factors in local CRC pathogenesis. This suggests that the effectiveness of prospective microbiome monitoring for adenomas may be limited but supports the potential causality of these consistent, early microbial changes in colonic neoplasia.

Study phs002343

MP2PRT: Genomic and Molecular Characterization of Biomarkers Associated with Tumor Angiogenesis, DNA Repair, and Immunologic Tolerance using Samples from the NRG Oncology Phase 3 Randomized Trial, GOG-0240 (NCT00803062)

The Molecular Profiling to Predict Response to Treatment (MP2PRT) program is part of the NCI's Cancer Moonshot Initiative. The aim of this program is the retrospective characterization and analysis of biospecimens collected from completed NCI-sponsored trials of the National Clinical Trials Network and the NCI Community Oncology Research Program. This study is one of the selected studies under this program. For this study, genomic characterization (WGS, WXS, Total RNAseq, miRNAseq) has been performed on cervical tumor tissue from patients with advanced disease (persistent, recurrent, and metastatic) and matching germline samples. It is hypothesized that the characterization of these tissues using next generation sequencing will lead to the identification of relevant novel genetic aberrations within the immunologic, DNA repair, and tumor angiogenesis domains that dichotomize the study population into exceptional responders and non-responders to systemic therapy, with a spectrum of response manifesting between the two extremes.

Study phs002293

California Teachers Study (CTS): Whole Genome Sequences From Under-Represented Populations

The California Teachers Study (CTS) is a prospective observational cohort of N=133,477 adult women who have been followed since 1995. Participants completed up to six surveys and have been linked with cancer, hospitalization, and mortality data. In 2013-2016, over 14,000 CTS participants donated blood samples for future research. For this project, DNA was extracted in 2023 from 1694 buffy coats and 56 blood clots from N=1750 CTS participants whose self-reported race/ethnicity was Asian (398), Asian or Pacific Islander (18), Black or African American (189), Native American (128), Native Hawaiian or Other Pacific Islander (66), White Hispanic (719), or more than one race (232). Whole genome sequencing (WGS) was performed at CIDR in 2023-2024. WGS data and accompanying phenotype data are available through dbGaP. In addition, all CTS data are available to the research community via the CTS Researcher Platform (www.calteachersstudy.org), a secure cloud-based environment that includes data, software, documentation, and collaboration workspaces.

Study phs002918

12298 results for "cancer rna-seq"

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