17489 results for "the best way to get coins in fc 26 Navštivte Buyfc26coins.com Společnost známá transparentními transakcemi..CQ2q"

in 19.65 milliseconds.

• NRG-GY017: Atezolizumab before and/or with Chemoradiotherapy in Immune System Activation in Patients with Node Positive Stage IB2, II, IIIB, or IVA Cervical Cancer

  Locally advanced cervical cancer remains an area of high therapeutic unmet need, with ~50% of patients developing disease recurrence despite treatment with chemotherapy combined with radiation. Combination of immune checkpoint blockade with chemoradiation has been explored in this setting, but optimal sequencing of these modalities is unknown. To address this question, we developed and conducted the NCI sponsored trial “Anti PD-L1 (Atezolizumab) as an Immune Primer and Concurrently with Extended Field Chemoradiotherapy for Node Positive Locally Advanced Cervical Cancer”, randomizing patients to atezolizumab administration prior to and concurrent with chemoradiation therapy (CRT) vs. concurrent with CRT (NRG-GY017; N=40, ClinicalTrials.gov Identifier: NCT03738228). Patients were randomized to atezolizumab neoadjuvant and concurrent (Arm A) or concurrent with CRT (Arm B). The study closed to successful accrual of 36 evaluable patients in June 2020. Out of 40 patients consented patients, 4 were never treated. The reasons for that are: 2 were screen failures, 1 withdrew consent, and 1 was not treated due to physician preference. The study incorporated comprehensive collection of pre- and on-treatment tumor biopsies as well as multitime point blood collections. T cell receptor (TCR) sequencing was performed on the tumors as well as pre- and on-treatment peripheral blood, and the data are included with dbGaP submission. Among the 36 eligible and treated patients, there were 30 (17 on Arm A and 13 on Arm B) with pre- and on-treatment peripheral TCR sequencing data. Twenty-five patients (14 in Arm A and 11 in Arm B) had additional tumor TCR sequencing data available, which enabled tracking of tumor-associated TCR clones in peripheral blood. We demonstrate that neoadjuvant atezolizumab administration results in peripheral expansion of higher proportion of tumor-associated TCR clones in Arm A than in Arm B and is associated with favorable 2-year disease-free survival (DFS). No new safety signals were identified. These findings support further evaluation of the neoadjuvant IO and CRT sequencing strategy in locally advanced cervical cancer.

  Study phs003833

• Hereditary Gastric Cancer Syndromes: An Integrated Genomic and Clinicopathologic Study of the Predisposition to Gastric Cancer

  Gastric cancers are cancers of the stomach. Hereditary cancers are passed from parent to child. Researchers want to gather data about hereditary gastric cancers. Bulk RNA sequencing (RNA-seq) of signet ring cells (SRCs) and adjacent non-SRC epithelium (NEP) was performed on laser-capture microdissected (LCM) regions of interest found in risk-reducing total gastrectomy specimens from hereditary diffuse gastric cancer (HDGC) patients (Clinicaltrials.gov ID: NCT03030404). Twenty patients (6 male, 14 female) with confirmed HDGC were identified. Analysis of differentially expressed genes (DEGs) demonstrated upregulation of certain individual epithelial–mesenchymal transition (EMT) and proliferation genes. SRC regions had significant enrichment in pathways involved in T cell signaling. CIBERSORTx predicted significant increases in the presence of regulatory T cells (Tregs) specific to SRC regions.

  Study phs003422

• RNA-seq analysis of transcriptome variation with human ESC subclones

  Many studies over the past 10 years, culminating in the recent report of the International Stem Cell Initiative (ISCI, 2011) have shown that hPSC acquire genetic and epigenetic changes during their time in culture. Many of the genetic changes are non-random and recurrent, probably because they provide a selective growth advantage to the undifferentiated cells. Some are shared by embryonal carcinoma cells, the malignant counterparts of ES cells. The origins of these growth advantages are poorly understood, but may come from altered cell cycle dynamics, resistance to apoptosis or altered patterns of differentiation. Less is known about the nature and consequences of epigenetic changes, but it is likely that these similarly affect hPSC behaviour; e.g., enhanced expression of DLK1, an imprinted gene, is associated with altered hPSC growth (Enver et al 2005). Inevitably, these genetic and epigenetic changes will impact on our ability to use hPSC for regenerative medicine, either because malignant transformation of the undifferentiated cells or their differentiated derivatives to be used for transplantation compromises safety, or because they impede the function of those differentiated derivatives, or because they affect the efficiency with which the undifferentiated cells can be expanded and differentiated into desired cell types. Focusing initially upon the existing clinical grade hESC lines, later moving to iPSC, we will Consolidate and extend knowledge of the rate, type and functional impact of the genetic variations that occur during hPSC culture. We will use whole genome and exome sequencing as well as SNP arrays, together with clonal analysis and other cytogenetics techniques. Common changes will be compared with those found in the normal human population, at low frequency in the original cell population or observed during iPSC generation in the HIPSCI project currently based at the WTSI. These studies will provide a better understanding of the range of genetic changes that occur in hPSC beyond the CNVs already identified. In conjunction with cancer genome resources and expertise at WTSI, bioinformatic analyses of these hPSC data will allow us to assess potential impact on hPSC behaviour pertinent to applications in regenerative medicine, notably the likelihood that specific changes arising in undifferentiated PSC cultures may be associated with potential malignant transformation of differentiated progeny This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/ .

  Dataset EGAD00001004266

• National Cancer Institute (NCI) Non-Hodgkin Lymphoma Genome-wide Association Study (GWAS)

  Within the framework of the International Lymphoma Epidemiology Consortium (InterLymph) Consortium and NCI-sponsored Cohort Consortium, investigators from 22 studies came together to conduct a genome-wide association study (GWAS) of non-Hodgkin lymphoma (NHL). The goal of the study was to identify common genetic variants associated with the risk of NHL. As described previously (Berndt SI et al., Nature Genetics, 2013, PMID: 23770605 ), cases and controls from 22 studies, including nine prospective cohort studies, eight population-based case-control studies, and five clinic or hospital-based case-control studies were included in this effort. Cases of NHL were ascertained from cancer registries, clinics or hospitals, or through self-report verified by medical and pathology reports. The phenotype information for all NHL cases was reviewed centrally at the InterLymph Data Coordinating Center and harmonized according to the hierarchical classification proposed by the InterLymph Pathology Working Group based on the World Health Organization (WHO) classification (2008). Controls were frequency matched to cases on age and gender by study, and the study was limited to subjects of European ancestry. Participants were genotyped using the Illumina Omni Express. The NCI Non-Hodgkin Lymphoma GWAS is utilized in the following dbGaP sub-studies. To view genotypes and derived variables collected in these sub-studies, please click on the following sub-studies below or in the "Sub-studies" box located on the right hand side of this top-level study page phs000801 NCI Non-Hodgkin Lymphoma GWAS. phs000802 NCI Non-Hodgkin Lymphoma GWAS: CLL phs000818 NCI Non-Hodgkin Lymphoma GWAS: Controls phs000889 NCI Non-Hodgkin Lymphoma GWAS: DLBCL phs000890 NCI Non-Hodgkin Lymphoma GWAS: FL phs000891 NCI Non-Hodgkin Lymphoma GWAS: MZL

  Study phs000801

• Dynamics of Tumor Heterogeneity from Primary to Metastatic Dissemination in Prostate Cancer

  PRO-SPeCT: PROstate cancer heterogeneity deconvolution through Single cell Profiling of Chromatin accessibility and Transcriptomic output Identifying drivers of cancer progression to guide treatment selection is hindered by limited abilities to understand tumor heterogeneity’s impact on evolution. Here, we delineated the phenotypic variability across ~300,000 prostate tumor cells collected from multiple loci in primary and matched locoregional metastases. We found inter-patient heterogeneity to be confined to malignant populations. While malignant cell populations exhibit intra-locus heterogeneity, they maintain inter-loci phenotypic similarity within a patient’s prostate gland. In addition, the intra-locus heterogeneity between malignant cell populations is paired with a common clonal architecture. Lastly, we show that malignant cell populations disseminating to locoregional lymph nodes mirror the clonal architecture and phenotypic heterogeneity observed across primary tumor loci while showcasing cell state transition toward inflammatory phenotypes. These findings provide insights into distinct measures of tumor heterogeneity, revealing diverse evolutionary paths across patients converging to common phenotypic adaptations in early prostate cancer progression.

  Study EGAS50000000524

• Indonesian Genome Diversity Project 3

  Low coverage whole genome sequences were collected to study the population history in Eastern Indonesia, in particular Wallacea and Papua region. We have sequenced the genomes of 254 individuals from 12 Wallacean and 3 Papuan populations spanning this geographical region.

  Study EGAS50000000447

• Comprehensive molecular and clinicopathological profiling of desmoid tumors

  Previous studies have not clearly identified a prognostic factor for desmoid tumors (DT). Whole-exome sequencing and/or RNA sequencing were performed in 64 cases of DT to investigate the molecular profiles in combination with the clinicopathological characteristics.

  Study JGAS000270

• Sample Multiplexing Oligo Comparison

  In this study, we compared various multiplexing reagents, including MULTI-Seq, Hashtag antibody, and CellPlex, in patient-derived xenografts (PDXs). We found that all multiplexing reagents worked well in cell types robust to ex vivo manipulation but suffered from signal-to-noise issues in more delicate sample types. We also compared the performance of fixed scRNA-Seq kits and CRISPR-based destruction of non-informative genes.

  Study EGAS50000000153

• The Immunogenetics of Measles Immunity - Measles (MMR) vaccination (NIAID/NIH)

  To examine the role of gene polymorphisms (including functional studies of SNPs) on variations in vaccine-induced immune responses, in approximately 3,000 healthy school-age children, adolescents and young adults/adults, who were vaccinated with measles-containing vaccine (MMR). To achieve greatest power to detect SNPs associated with measles-specific immune response phenotypes, we pooled our data across three genotyping platforms and three cohorts (US cohort, San Diego cohort and Rochester cohort).

  Study phs001630

• Multi-Omic Profiling of Glioma Patient Tumors and Patient-Derived Model Systems

  We have created a resource of transcriptomic (RNAseq), genomic (whole-exome seq), and lipidomic (untargeted shotgun) profiling data from over 175 molecularly diverse glioma tumors and derivative models in orthotopic mouse xenografts and gliomasphere cultures from over 110 unique patient tumor lines. Provided in this dataset are matched bulk RNA and whole-exome paired-end sequencing data from resected gliomas and derived model systems performed on Illumina HiSeq and NovaSeq sequencing instruments. This comprehensive dataset powers multiple studies aiming to derive molecular signatures of intertumoral heterogeneity and perturbation responses in glioma. Through integrative multi-omic analyses in Minami, et al., 2023, PMID: 37236196, we identified that CDKN2A deletion remodels the GBM lipidome and consequently primes CDKN2A-deleted tumors for ferroptosis. Lipidomics data related to this study are publicly available here. In another study, we used a combination of molecular profiling and functional profiling of apoptotic potential to stratify patients into groups with differential vulnerability to the current standard-of-care in gliomas, and in combination with drugs targeting intrinsic apoptosis, largely informed but not limited to TP53 mutation status.

  Study phs003286

• Molecular dissection of germline chromothripsis in a developmental context

  Complex germline genomic rearrangements can affect many genes and regulatory elements, but the precise mechanisms that caused the phenotype of patients with such rearrangements are often unknown. To dissect the impact of germline chromothripsis in a relevant developmental context, we performed trio-based RNA expression analysis on blood cells,induced pluripotent stem (iPS) cells and iPS-cell derived neuronal cells from a patient with de novo germline chromothripsis and both healthy parents. In addition, we performed Hi-C on iPS cell-derived neural progenitors of the patient and the father to study the effects of the chromothripsis rearrangements on the architecture of the derivative chromosomes. We demonstrate that a combination of patient-derived iPS cell differentiation and trio-based molecular profiling is a powerful approach to improve the interpretation of pathogenic complex genomic rearrangements.

  Study EGAS00001001896

• The Mutational Landscape of Head and Neck Squamous Cell Carcinoma

  This study was the first-known large-scale effort to uncover the mutational spectrum of head and neck cancers. We analyzed whole-exome sequence from 92 tumor-normal pairs and retained 74 of them for significance analysis. The majority exhibited a mutational profile consistent with tobacco exposure; human papilloma virus sequence was detectable in 15% of cases. In addition to identifying previously known HNSCC genes (TP53, CDKN2A, PTEN, PIK3CA, and HRAS), the analysis revealed many genes not previously implicated in this malignancy. At least 30% of cases harbor mutations in genes (such as NOTCH1, IRF6, TP63) that regulate squamous differentiation, implicating alterations in this process as a major driver of HNSCC carcinogenesis. Altogether, the results suggest that large-scale exome sequencing may illuminate fundamental tumorigenic mechanisms with important therapeutic implications.

  Study phs000370

• Melanoma_brain_metastases

  This is a whole exome study of brain metastases in melanoma. We are studying the genomic evolution of primary cutaneous melanoma to brain met in patients with brain-only metastatic disease. We are also looking at the genomic heterogeneity in patients with temporally, anatomically and regionally separated brian metastases.

  Study EGAS00001002107

• Whole-genome sequencing across 449 samples spanning 47 ethnolinguistic groups provides insights into genetic diversity in Nigeria

  African populations have been drastically underrepresented in genomics research and failure to capture the genetic diversity across the numerous ethnolinguistic groups (ELGs) found in the continent has hindered the equity of precision medicine initiatives globally. Here, we describe the whole-genome sequencing of 449 Nigerian individuals across 47 unique self-reported ELGs. Population structure analysis reveals genetic differentiation amongst our ELGs, consistent with previous findings. From the 36 million SNPs and indels discovered in our dataset, we provide a high-level catalog of both novel and medically-relevant variation present across the ELGs. These results emphasize the value of this resource for genomics research, with added granularity by representing multiple ELGs from Nigeria. Our results also underscore the potential of using these cohorts with larger sample sizes to improve our understanding of human ancestry and health in Africa.

  Study EGAS00001007036

• An analysis of humoral and cellular immune responses following COVID-19 vaccination.

  Two dose mRNA vaccination provides excellent protection against SARS-CoV-2. However, there are few data on vaccine efficacy in elderly individuals above the age of 801. Additionally, new variants of concern (VOC) with reduced sensitivity to neutralising antibodies have raised fears for vulnerable groups. Here we assessed humoral and cellular immune responses following vaccination with mRNA vaccine BNT162b22 in elderly participants prospectively recruited from the community and younger health care workers. Median age was 72 years and 51% were females amongst 140 participants. Neutralising antibody responses after the first vaccine dose diminished with increasing age, with a steep drop in participants over 80 years old. Sera from participants below and above 80 showed significantly lower neutralisation potency against B.1.1.7, B.1.351 and P.1. variants of concern as compared to wild type. Those over 80 were more likely to lack any neutralisation against VOC compared younger participants following first dose. Binding IgG and IgA antibodies were lower in the elderly, as was the frequency of SARS-CoV-2 Spike specific B- cells. We observed a trend towards lower somatic hypermutation in participants with suboptimal neutralisation, and elderly participants demonstrated clear reduction in class switched somatic hypermutation, driven by the IgA1/2 isotype. SARS-CoV-2 Spike specific T- cell IFN?? and IL-2 responses were secreted primarily by CD4 T cells, and impaired in the older age group. We conclude that the elderly are a high risk population that warrant specific measures in order to mitigate against vaccine failure, particularly where variants of concern are circulating. Specifically, the dosing interval should not be extended in this group.

  Study EGAS00001005380

• MutWP5__CRUK_Mutographs_of_Cancer__Lung__PD37920__WG_

  Sequencing of LCM-derived microbiopsies from explanted lung from COPD patient. Goal to assess the mutational burden, spectrum, and clonal dynamics within the tissue. Deep sampling throughout multiple regions of the lung will determine whether there are differences in smoking-related mutation burden in different portions of the lung. Whole-genome sequencing will be conducted on samples identified as promising from the initial targeted data. Results from this portion of the study will be compared to other individuals with smoking-related diseases (COPD, pulmonary fibrosis, lung cancer), and normal, non-smoking lungs.

  Study EGAS00001003320

• MutWP5__CRUK_Mutographs_of_Cancer__Lung__PD38233__WG_

  Sequencing of LCM-derived microbiopsies from explanted lung from COPD patient. Goal to assess the mutational burden, spectrum, and clonal dynamics within the tissue. Deep sampling throughout multiple regions of the lung will determine whether there are differences in smoking-related mutation burden in different portions of the lung. Whole-genome sequencing will be conducted on samples identified as promising from the initial targeted data. Results from this portion of the study will be compared to other individuals with smoking-related diseases (COPD, pulmonary fibrosis, lung cancer), and normal, non-smoking lungs.

  Study EGAS00001003322

• MutWP5__CRUK_Mutographs_of_Cancer__Lung__PD38234__WG_

  Sequencing of LCM-derived microbiopsies from explanted lung from pulmonary fibrosis patient. Goal to assess the mutational burden, spectrum, and clonal dynamics within the tissue. Deep sampling throughout multiple regions of the lung will determine whether there are differences in smoking-related mutation burden in different portions of the lung. Whole-genome sequencing will be conducted on samples identified as promising from the initial targeted data. Results from this portion of the study will be compared to other individuals with smoking-related diseases (COPD, pulmonary fibrosis, lung cancer), and normal, non-smoking lungs.

  Study EGAS00001003324

• MutWP5__CRUK_Mutographs_of_Cancer__Lung__PD43291_Novaseq__Exome_

  Sequencing of LCM-derived microbiopsies from explanted lung from COPD patient. Goal to assess the mutational burden, spectrum, and clonal dynamics within the tissue. Deep sampling throughout multiple regions of the lung will determine whether there are differences in smoking-related mutaiton burden in different portions of the lung. Whole-genome sequencing will be conducted on samples identified as promising from the initial targeted data. Results from this poriton of the study will be compared to other individuals with smoking-related diseases (COPD, pulmonary fibrosis, lung cancer), and normal, non-smoking lungs.

  Study EGAS00001003503

• RNA stability controlled by m6A methylation contributes to X-to-autosome dosage compensation in mamals

  In mammals, X-chromosomal genes are expressed from a single copy since males (XY) possess a single X chromosome, while females (XX) undergo X inactivation. To compensate for this reduction in dosage compared to two active copies of autosomes, it has been proposed that genes from the active X chromosome exhibit dosage compensation. However, the existence and mechanism of X-to-autosome dosage compensation are still under debate. Here, we show that X-chromosomal transcripts are reduced in m6A modifications and more stable compared to their autosomal counterparts. Acute depletion of m6A selectively stabilises autosomal transcripts, resulting in perturbed dosage compensation in mouse embryonic stem cells. We propose that higher stability of X-chromosomal transcripts is directed by lower levels of m6A, indicating that mammalian dosage compensation is partly regulated by epitranscriptomic RNA modifications.

  Dataset EGAD00001010194

• Identification and characterization of tertiary lymphoid structures in brain metastases

  Brain metastases (BrM) are the most common cancers in the brain. We performed transcriptome-wide gene expression profiling combined with spatial immune cell profiling to characterize the tumor immune microenvironment in BrM from different primary tumors. We found that BrM from lung carcinoma and malignant melanoma showed overall higher immune cell infiltration as compared to BrM from breast carcinoma. RNA sequencing-based immune cell deconvolution revealed gene expression signatures indicative of tertiary lymphoid structures (TLS) in subsets of BrM from lung cancer and melanoma. This finding was corroborated by multiplex immunofluorescence staining of immune cells in BrM tissue sections. Detection of TLS signatures was associated with prolonged survival after BrM diagnosis in lung cancer patients. Our findings highlight the cellular diversity of the tumor immune microenvironment in BrM of different cancer types and suggest a role of TLS formation for BrM patient outcome.

  Study EGAS50000000563

• A mechanistic classification of clinical phenotypes in neuroblastoma

  Clinical courses of the pediatric tumor neuroblastoma range from fatal progression to spontaneous regression. To gain insights into the pathogenesis of these divergent subtypes, we performed massively parallel sequencing of 416 pretreatment neuroblastomas and assessed telomere maintenance mechanisms in 208/416 cases. We observed that telomere maintenance and mutations in RAS or p53 pathway genes strongly affected disease courses. Fatal outcome occurred only in the presence of telomere maintenance, whereas patients whose tumors lacked such mechanisms had excellent outcome. In patients with telomere maintenance-positive tumors, survival was dramatically inferior when additional RAS/p53 pathway mutations were present. By contrast, spontaneous regression occurred both in the presence and absence of RAS/p53 pathway mutations in patients with telomere maintenance-negative tumors. Together, our data provide a precise mechanistic classification of clinical neuroblastoma phenotypes based on telomere maintenance mechanisms and genetic alterations of the tumor.

  Study EGAS00001003244

• Gabriella Miller Kids First Pediatric Research Program: An Integrated Clinical and Genomic Analysis of Treatment Failure in Pediatric Osteosarcoma

  The Gabriella Miller Kids First Pediatric Research Program (Kids First) is a trans-NIH effort initiated in response to the 2014 Gabriella Miller Kids First Research Act and supported by the NIH Common Fund. This program focuses on gene discovery in childhood cancers and structural birth defects and the development of the Gabriella Miller Kids First Pediatric Data Resource (Kids First Data Resource). Both childhood cancers and structural birth defects are critical and costly conditions associated with substantial morbidity and mortality. Elucidating the underlying genetic etiology of these diseases has the potential to profoundly improve preventative measures, diagnostics, and therapeutic interventions. All of the WGS and phenotypic data from this study are accessible through dbGaP and kidsfirstdrc.org, where other Kids First datasets can also be accessed. Although the survival of children with relapsed osteosarcoma is very poor, little is known about the etiology of treatment failure in this disease. The purpose of this project is to perform whole genome sequencing on serial samples from patients with osteosarcoma obtained before treatment, after treatment, and at relapse/metastasis in order to identify the mutations and pathways that are drivers of drug resistance. If successful, our results may help identify patients at high risk for treatment failure and may yield new treatments for children who cannot currently be cured.

  Study phs001714

• Rapid Acceleration of Diagnostics - Underserved Populations (RADx-UP): COVID-19 Testing and Vaccination Social Network Diffusion for Diverse Criminal Legal Involved Communities

  This RADx-UP Phase II proposal, "Social network diffusion of COVID-19 prevention for diverse Criminal Legal Involved Communities", will implement a situation appropriate COVID-19 testing and vaccination social network diffusion intervention - C3 - building upon RADx-UP Phase I lessons and successful social network prevention interventions developed previously by the research team. C3 Criminal Legal Involved (CLI) populations encompass those non-incarcerated who have experienced recent arrest, incarceration, probation, parole or diversion programs such as drug courts. While increases in COVID-19 testing have been observed among this group, there remain members with limited testing history as well as individuals who are vaccine hesitant. COVID-19 prevention messaging can no longer be simplified to "everyone test and/or everyone vaccinate" as testing and vaccination decisions among community members are sensitive to personal histories (i.e., prior infection), local infection rates (i.e., low rates) and testing/vaccination availability. As COVID-19 prevention efforts have become more complicated (i.e., test if exposed), people tend to focus on the messenger, and particularly those that are close to them. Personal connections and communications within existing personal network structures, such as families, friends and other trusted acquaintances represent the cornerstone to increase situation appropriate testing and overcoming COVID-19 vaccine hesitancy. C3 builds upon RADx-UP I, by using a network diffusion approach facilitated through motivational interviewing purposefully geared to mobilize one's own organic social network to increase context appropriate testing and vaccine uptake. Through this process we will maximize the primary benefit and impact of this type of intervention which also has the intended effect of increasing likelihood that the messenger themselves will undergo the same behavior change that they have been trained to promote. We will leverage infrastructure developed in RADx-UP Phase I, which includes 4 high-impact sites across the Central US from Phase I: Baton Rouge LA, Little Rock AR, Indianapolis IN, and Chicago IL. We will utilize established engagement efforts already in place and continue to fully integrate communities in the strategic application of the intervention. We will use the RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) framework to guide implementation. C3 aims to: Aim 1a. Test the efficacy (3-month situation appropriate testing or vaccination) of a network diffusion intervention (C3) versus an existing COVID-19 testing and vaccine linkage to care intervention among: 1) primary study participants (primary outcome); and 2) secondary study participants connected to primary participants (secondary outcome) using a RCT design. Aim 1b. Explore the mechanisms for differential intervention effects at the individual and network-level that may increase situation appropriate testing and/or vaccination uptake. Aim 2. Examine key RE-AIM components in real time tied to the implementation of the network diffusion intervention (C3).

  Study phs003234

• Maintenance of Brain Tumor Profile on Organotypic Brain Slice Culture (OBSC)

  We used uncultured tumor resection tissue from an NF2 mutation-driven grade II meningioma (MG-II) to investigate whether tumors engrafted onto organotypic brain slice cultures (OBSCs) maintained the genetic profile of the parent tumor. We prepared three groups of samples for whole exome sequencing (WES) from the same pool of dissociated MG-II tissue. Group HT is the original uncultured human tumor tissue (n = 3). Group CL is the parent tumor tissue expanded in standard in vitro cell culture until the minimum number of cells required for WES had grown. Because of initial cell loss and subsequent clonal expansion, this required six passages over the span of approximately one month (n = 3). Group BSHT is the uncultured tumor resection tissue engrafted onto OBSCs and subsequently dissected from the OBSCs at the conclusion of our standardized assay length (4 days; n = 4). WES analysis showed that tumor tissue engrafted onto OBSCs maintained a significant genetic resemblance to the parent tumor, while tumor tissue expanded in vitro displayed a distinctly different profile. Furthermore, the mutational profiles of all four BSHT biological replicates were markedly similar, indicating that each OBSC-engrafted tumor indeed contained a representative sample of the original patient tumor. A closer look at the hallmark NF2 mutations existing within all samples revealed that while all samples from the original tumor (HT1-3) and the OBSC-engrafted tumor (BSHT1-4) maintain the frame shift deletion at V24, this mutation was lost in all samples expanded in vitro (CL1-3) and replaced by mutations in other areas. Together, this data suggests that the rapid assay design and tumor-accommodating niche of our OBSC platform enables effective maintenance of the original patient tumor profile. The BBsplit algorithm from the BBtools suite was run on all samples to eliminate rat DNA contamination in the BSHT samples as well as to account for any biases that may result as a part of that process. Only the reads that were binned to the human reference were used for subsequent analysis. Reads were then mapped to the GRCh38 version of the human genome with BWA v0.7.17 and realigned together with ABRA2 v.23. Quality control was implemented using the GATK/Picard v4.1.7.0 toolkit. Somatic variants were called for each sample using the MuTect2 algorithm v4.1.7.0. Variants were merged into a single cohort variant call file and then converted to MAF via vcf2maf v1.6.21 tool. Variants were annotated using VEP v87. To identify mutations with potentially high biological impact, multiple filtering steps were applied to somatic mutation calling. First, we selected only the somatic variants that passed all filters from the MuTect2 FilterMutectCalls algorithm and second, only high/moderate impact (change coding) variants as defined by the VEP annotation were further analyzed. Over 1900 single nucleotide variants (SNVs) were detected across all samples. Figures that summarized the results were generated using maftools.

  Study phs003268