GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 80, No. 14_Supplement ( 2020-07-15), p. B06-B06
    Abstract: The purpose of our study was to elucidate the molecular mechanisms by which the histone H3 K27M mutation drives tumorigenesis of pediatric gliomas. Though it has potential implications on the treatment of diffuse midline glioma as a disease driver, the timing, cell type of origin, and effect of the H3K27M mutation on early embryonic brain development are not fully characterized. Here, we performed differential expression analysis on a cohort of H3K27M and H3WT pediatric gliomas, revealing that genes in the epithelial-mesenchymal transition (EMT) pathway were significantly differentially expressed. SNAI1, the EMT master regulator, was significantly overexpressed in the H3K27M tumor cohort. Overall, pre-EMT genes were overexpressed in H3K27M tumors while post-EMT genes were underexpressed. We hypothesized that H3K27M may lead to gliomagenesis by stalling an EMT in early brain development and employed single-cell and bulk RNA sequencing data from cerebral organoids at multiple developmental timepoints to test this hypothesis. We observed that a long noncoding RNA (lncRNA) signature identified as transiently expressed in early brain development was preferentially expressed in H3K27M tumors. Cell type-specific lncRNA signatures had higher expression in H3K27M tumors for pre-EMT cell types, and higher expression in H3WT tumors for post-EMT cell types. Finally, t-SNE clustering of single-cell glioma RNA sequencing data with single-cell organoid data revealed transcriptional similarities between H3K27M and pre-EMT neural stem cells. In conclusion, we observed aberrant activity of the EMT in H3K27M gliomas. Our data suggest that the H3K27M mutation is associated with a pre-EMT cell phenotype, and that this mutation may cause EMT arrest or de-differentiation. Citation Format: Allison R. Cheney, Lauren M. Sanders, Lucas Seninge, Holly C. Beale, Ellen Towle Kephart, Jacob Pfeil, Katrina Learned, A. Geoffrey Lyle, Isabel Bjork, David Haussler, Sofie R. Salama, Olena M. Vaske. Candidate differentiation stall in epithelial mesenchymal transition in H3K27M diffuse midline glioma [abstract]. In: Proceedings of the AACR Special Conference on the Advances in Pediatric Cancer Research; 2019 Sep 17-20; Montreal, QC, Canada. Philadelphia (PA): AACR; Cancer Res 2020;80(14 Suppl):Abstract nr B06.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2020
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 80, No. 16_Supplement ( 2020-08-15), p. 6154-6154
    Abstract: Pediatric diffuse midline gliomas are lethal cancers, the majority of which harbor the H3 p.K27M mutations. Although it has potential implications on the treatment of diffuse midline glioma as a disease driver; the timing, cell type of origin, and effect of the H3 p.K27M mutation on early embryonic brain development is poorly understood. The purpose of our study is to elucidate the molecular mechanisms by which the histone H3 p.K27M mutation drives tumorigenesis of pediatric diffuse midline gliomas using the analysis of genomic datasets. Here, we performed differential RNA sequencing gene expression analysis of a cohort of H3K27M and H3 wild type (WT) pediatric diffuse midline gliomas, revealing that genes in the epithelial-mesenchymal transition (EMT) pathway were significantly differentially expressed between the mutant and WT tumors. Several EMTs are required for normal brain development. Overall, pre-EMT genes, including the master regulator of EMT SNAI1, were overexpressed in H3K27M tumors compared to the WT tumors, while post-EMT genes were underexpressed. We hypothesized that the H3 p.K27M mutation may lead to gliomagenesis by inducing a stall in the EMT in early brain development. To test this hypothesis, we examined published single-cell RNA sequencing data from pediatric diffuse midline gliomas alongside similar data from organoid models of neural development, collected from multiple developmental timepoints. This analysis revealed transcriptional similarities between H3K27M and pre-EMT neural stem cells. Currently, we are investigating the expression of EMT markers in H3K27M and WT pediatric glioma primary cell lines, using Western blotting, RT-PCR, and CRISPRi screening. In conclusion, we observed aberrant expression of genes involved in EMT in H3K27M pediatric gliomas. Our observations are consistent with a model in which the p.H3K27M mutation is associated with a pre-EMT cell phenotype, potentially due to an arrest in the EMT pathway or de-differentiation of mature astrocytes. Citation Format: ALLISON R. CHENEY, Lauren M. Sanders, Lucas Seninge, Holly C. Beale, Ellen Towle Kephart, Jacob Pfeil, Katrina Learned, A. Geoffrey Lyle, Isabel Bjork, David Haussler, Sofie R. Salama, Olena M. Vaske. H3K27M gliomas are characterized by a stall in the epithelial-mesenchymal transition [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6154.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2020
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Molecular Case Studies, Cold Spring Harbor Laboratory, Vol. 5, No. 5 ( 2019-10), p. a004317-
    Abstract: Gliomatosis peritonei is a rare pathologic finding that is associated with ovarian teratomas and malignant mixed germ cell tumors. The occurrence of gliomatosis as a mature glial implant can impart an improved prognosis to patients with immature ovarian teratoma, making prompt and accurate diagnosis important. We describe a case of recurrent immature teratoma in a 10-yr-old female patient, in which comparative analysis of the RNA sequencing gene expression data from the patient's tumor was used effectively to aid in the diagnosis of gliomatosis peritonei.
    Type of Medium: Online Resource
    ISSN: 2373-2865 , 2373-2873
    Language: English
    Publisher: Cold Spring Harbor Laboratory
    Publication Date: 2019
    detail.hit.zdb_id: 2835759-0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 81, No. 13_Supplement ( 2021-07-01), p. 3035-3035
    Abstract: Synovial sarcoma (SS) is an aggressive soft-tissue malignancy, accounting for 10% of all soft-tissue sarcomas. These tumors can occur at any age but most often affect young adults and adolescents, developing deep in the distal extremities. The prognosis of SS tumors is poor, with a 5-year survival rate of 36-76%, a high rate of metastasis and few treatments. The purpose of this study was to identify novel overexpressed oncogenes that could serve as druggable targets for treating synovial sarcoma patients. We compared the RNA-Seq expression profiles of a cohort of 36 synovial sarcomas to our compendium of RNA-Seq expression data from 12,236 tumor samples (treehousegenomics.ucsc.edu) from pediatric and adult cancer patients. In comparing gene expression in the synovial sarcoma cohort samples against the compendium samples, gene expression outliers were defined as having expression above the gene-specific outlier threshold as defined by the Tukey's outlier method. Among the overexpression outliers, pathway enrichment analysis was used to identify common and druggable pathways, with implications for potential therapeutics for patients with SS. Our analysis identified the overexpression of members of the Sonic Hedgehog pathway in the majority of synovial sarcoma samples. For example, GLI1 expression exceeded the outlier threshold in 35 out of 36 samples. This pathway can be targeted by available small molecule inhibitors. Ongoing work focuses on evaluating the role of Sonic Hedgehog signaling in the pathogenesis of SS using pharmacological inhibition, CRISPRi studies in cell line models of the disease and nanopore sequencing. We currently have 4 patient-derived synovial sarcoma cell lines (HSSY-II, SYO-1, YAMATO, and ASKA) that we can grow in both adherent conditions and in 3D cell culture as sarcospheres. We detected the expression of the SYT-SSX fusion transcript in each of the cell lines by RT-PCR to confirm the cell lines maintained expression of the pathogenic fusion. This work has implications for using comparative tumor RNA-seq derived gene expression data for nominating novel druggable targets specific to synovial sarcoma tumors. Citation Format: Yvonne A. Vasquez, Jacob Pfeil, Letitia Mueller, Holly Beale, Alfred G. Lyle, Lauren Sanders, Katrina Learned, Ellen Kephart, Anouk van den Bout, Allison Cheney, Sahar Hosseinzadeh, Isabel Bjork, Sofie R. Salama, Olena Vaske. Identifying potential druggable targets for synovial sarcoma using comparative RNA-seq analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3035.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2021
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    In: GigaScience, Oxford University Press (OUP), Vol. 9, No. 12 ( 2020-12-15)
    Abstract: Diffuse midline gliomas with histone H3 K27M (H3K27M) mutations occur in early childhood and are marked by an invasive phenotype and global decrease in H3K27me3, an epigenetic mark that regulates differentiation and development. H3K27M mutation timing and effect on early embryonic brain development are not fully characterized. Results We analyzed multiple publicly available RNA sequencing datasets to identify differentially expressed genes between H3K27M and non-K27M pediatric gliomas. We found that genes involved in the epithelial-mesenchymal transition (EMT) were significantly overrepresented among differentially expressed genes. Overall, the expression of pre-EMT genes was increased in the H3K27M tumors as compared to non-K27M tumors, while the expression of post-EMT genes was decreased. We hypothesized that H3K27M may contribute to gliomagenesis by stalling an EMT required for early brain development, and evaluated this hypothesis by using another publicly available dataset of single-cell and bulk RNA sequencing data from developing cerebral organoids. This analysis revealed similarities between H3K27M tumors and pre-EMT normal brain cells. Finally, a previously published single-cell RNA sequencing dataset of H3K27M and non-K27M gliomas revealed subgroups of cells at different stages of EMT. In particular, H3.1K27M tumors resemble a later EMT stage compared to H3.3K27M tumors. Conclusions Our data analyses indicate that this mutation may be associated with a differentiation stall evident from the failure to proceed through the EMT-like developmental processes, and that H3K27M cells preferentially exist in a pre-EMT cell phenotype. This study demonstrates how novel biological insights could be derived from combined analysis of several previously published datasets, highlighting the importance of making genomic data available to the community in a timely manner.
    Type of Medium: Online Resource
    ISSN: 2047-217X
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2020
    detail.hit.zdb_id: 2708999-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    In: JAMA Network Open, American Medical Association (AMA), Vol. 2, No. 10 ( 2019-10-25), p. e1913968-
    Type of Medium: Online Resource
    ISSN: 2574-3805
    Language: English
    Publisher: American Medical Association (AMA)
    Publication Date: 2019
    detail.hit.zdb_id: 2931249-8
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    In: GigaScience, Oxford University Press (OUP), Vol. 10, No. 3 ( 2021-03-13)
    Abstract: The reproducibility of gene expression measured by RNA sequencing (RNA-Seq) is dependent on the sequencing depth. While unmapped or non-exonic reads do not contribute to gene expression quantification, duplicate reads contribute to the quantification but are not informative for reproducibility. We show that mapped, exonic, non-duplicate (MEND) reads are a useful measure of reproducibility of RNA-Seq datasets used for gene expression analysis. Findings In bulk RNA-Seq datasets from 2,179 tumors in 48 cohorts, the fraction of reads that contribute to the reproducibility of gene expression analysis varies greatly. Unmapped reads constitute 1–77% of all reads (median [IQR], 3% [3–6%] ); duplicate reads constitute 3–100% of mapped reads (median [IQR], 27% [13–43%] ); and non-exonic reads constitute 4–97% of mapped, non-duplicate reads (median [IQR], 25% [16–37%] ). MEND reads constitute 0–79% of total reads (median [IQR], 50% [30–61%] ). Conclusions Because not all reads in an RNA-Seq dataset are informative for reproducibility of gene expression measurements and the fraction of reads that are informative varies, we propose reporting a dataset's sequencing depth in MEND reads, which definitively inform the reproducibility of gene expression, rather than total, mapped, or exonic reads. We provide a Docker image containing (i) the existing required tools (RSeQC, sambamba, and samblaster) and (ii) a custom script to calculate MEND reads from RNA-Seq data files. We recommend that all RNA-Seq gene expression experiments, sensitivity studies, and depth recommendations use MEND units for sequencing depth.
    Type of Medium: Online Resource
    ISSN: 2047-217X
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2021
    detail.hit.zdb_id: 2708999-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 80, No. 14_Supplement ( 2020-07-15), p. A44-A44
    Abstract: Here we describe the utility of comparative RNA sequencing (RNA-seq) analysis in identifying cancer driver pathways and relevant therapeutics in childhood cancer, and we introduce a novel system for prioritizing gene targets based on analytical and published evidence. The purpose of our study was to evaluate the clinical utility of comparative N-of-1 gene expression analysis in identifying therapeutic options for pediatric patients with relapsed or recurrent cancers. The comparative analysis framework and large cancer background cohorts were developed at the Treehouse Childhood Cancer Initiative at UC Santa Cruz. We employed this analysis in a pilot study of 26 patients at the Lucile Packard Children’s Hospital. We analyzed RNA-seq data from 30 biopsied samples from 26 patient donors, including 16 sarcomas, 5 CNS tumors, 3 hematopoietic cancers, 1 liver, and 1 colon cancer. We compared gene expression from each child’s tumor biopsy to a background cohort of RNA-seq data from over 11,000 cancer patients, and also to a smaller cohort defined by molecular and histopathologic similarity to the child’s tumor biopsy. This comparison yielded outlier gene activations in the child’s biopsy compared to those in the background cohorts, reflecting cancer driver pathways in the child’s tumor that are actionable. We stratified each of the resulting therapeutic leads into 5 baskets: RTK activation, JAK/STAT signaling, PI3K/AKT/mTOR signaling, Cell Cycle activation, or Other. Because 27 of the 30 samples had more than one lead, we developed a novel scoring system to prioritize each sample’s therapeutic gene targets based on the analytical strength of the gene expression analysis result, and on published literature evidence for each gene as a biomarker indicative of drug response. We presented the results of our analysis in genomic consensus meetings at Stanford and surveyed the responses of clinicians and families on the utility of our analysis for treatment decisions. Here we report our experience with the method and highlight case studies in which this analysis informed treatment decisions. Citation Format: Lauren M. Sanders, A. Geoffrey Lyle, Holly C. Beale, Ellen Towle Kephart, Katrina Learned, Jennifer Peralez, Norman Lacayo, Arun Rangaswami, Sheri L. Spunt, Isabel Bjork, David Haussler, Sofie R. Salama, Olena M. Vaske. Comparative gene expression analysis for identification and prioritization of therapeutic targets in a cohort of childhood cancers [abstract]. In: Proceedings of the AACR Special Conference on the Advances in Pediatric Cancer Research; 2019 Sep 17-20; Montreal, QC, Canada. Philadelphia (PA): AACR; Cancer Res 2020;80(14 Suppl):Abstract nr A44.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2020
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 80, No. 16_Supplement ( 2020-08-15), p. 5464-5464
    Abstract: Gene expression analysis of single samples shows increasing promise for clinical applications. However, obtaining high quality RNA from a human tumor sample can be challenging because medical, surgical, and pathological requirements often lead to sparse or degraded RNA. The variability in RNA quality presents challenges for defining input sample requirements, which are required to calculate sensitivity, specificity and reference ranges as required for a Clinical Laboratory Improvement Amendments (CLIA)-approved test. Clinical analysis of a single RNA-Seq dataset for the purpose of gene expression profiling involves not only the patient's sample, but a comparison cohort. We use 12,236 total tumor samples and require at least 20 samples for within-disease comparisons. Many of these samples do not have associated metadata about the quality of the sample, and so we have prioritized quality measures that can be derived from the sequence data alone. In order to characterize variability present in RNA-Seq datasets, we analyzed paired-end Illumina RNA sequencing (RNA-Seq) data from 1088 tumor samples from 29 data providers. We categorized reads based on where and how well they map to the genome, as well as by their PCR duplicate status. We defined reference ranges for five types of reads found in sequencing data: unmapped (0-13%); multi-mapped (2-15%); mapped duplicate (2-66%); mapped non exonic (0-26%) and mapped, exonic, non-duplicate (MEND, 27-76%). Only 64% of the 1088 tumor samples had read type fractions within the reference ranges. Of the remainder, most exceeded the reference ranges of more than one type of read. We then measured the relationship of sensitivity and specificity to input MEND read depth. We subsampled 5 deeply sequenced samples. With each subsample, we identified exceptionally highly expressed genes and samples with similar gene expression profiles. With subsampling to 20 million MEND reads, we detected over-expressed genes (“up-outlier” genes) with a median sensitivity of 96.1% and specificity of 99.8%; sample similarity had 96.6% sensitivity and 100.0% specificity. We estimate that a sample sequenced to a depth of 70 million total reads will typically have sufficient data for the up-outlier and sample-similarity gene expression analysis assays described here. With this analysis, we have identified a conservative approach to measuring the quality of RNA-Seq read data, which can then be used to define the sensitivity and specificity of single-sample assays to support their ultimate clinical adoption. Citation Format: Holly C. Beale, Jacquelyn M. Roger, Matthew A. Cattle, Liam T. McKay, Katrina Learned, Geoff Lyle, Ellen T. Kephart, Rob Currie, Du Linh Lam, Lauren Sanders, Jacob Pfeil, John Vivian, Isabel Bjork, Sofie R. Salama, David Haussler, Olena M. Vaske. Determining accuracy of RNA sequencing data for gene expression profiling of single samples [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5464.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2020
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 77, No. 13_Supplement ( 2017-07-01), p. LB-338-LB-338
    Abstract: Genomic data sharing is increasingly recognized as critical to genomic research. The need is acute in pediatric cancer research due to the rarity of pediatric tumor types and paucity of pediatric cancer data, and in translational research to assess the impact of genomic research on human health. However, genomic data sharing is hindered by an absence of standards regarding timing, patient privacy, use agreement standards, and data characterization and quality. At UC Santa Cruz Treehouse Childhood Cancer Initiative (treehousegenomics.soe.ucsc.edu), we examine individual pediatric cancer tumor RNA sequencing profiles against a database of over 11,000 tumor RNA sequencing profiles from public genomic datasets such as The Cancer Genome Atlas, Therapeutically Applicable Research To Generate Effective Treatments, International Cancer Genome Consortium, and Medulloblastoma Advanced Genomics International, and pediatric cancer clinical trials with which we partner, such as those at Stanford University, UC San Francisco, Children’s Hospital of Orange County, and British Columbia Children’s Hospital. For over 18 months, we have worked systematically to enhance the Treehouse dataset by adding pediatric cancer data and presently underrepresented tumor types. The NIH and other leading funding agencies now regularly require grantees to make genomic data generated available to the research community, either post-publication or after an embargo period. We have combed websites and public repositories, searched PubMed, and contacted researchers directly. Finding data requires a mining of literature, often with limited information, and initiating the many different processes for requesting permission for these datasets, with different and often cumbersome data use obligations. The combination of cryptically named datasets, multiple data types and the practice of grouping datasets from multiple papers under a single study accession makes zeroing in on the correct dataset challenging. Downloading the genomic data is time-consuming, such that a dataset of under a 100 files can take up to a week to download under optimal conditions. Matching metadata is inconsistently available, often vague, sparse or error ridden. Only after months of identifying, permissioning for use, committing to use- and sharing-restricting terms, and downloading the genomic and metadata, is it possible to assess the quality, often discovering that data quality is low. We evaluate the barriers to data sharing based on the Treehouse experience and offer guidelines for timing, use agreement standards, and data characterization and quality, to enhance data sharing and outcomes for all pediatric cancer patients. Citation Format: Katrina Learned, Ann Durbin, Robert Currie, Holly Beale, Du Linh Lam, Theodore Goldstein, Sofie R. Salama, David Haussler, Olena Morozova, Isabel Bjork. A critical evaluation of genomic data sharing: Barriers to accessing pediatric cancer genomic datasets: a Treehouse Childhood Cancer Initiative experience [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-338. doi:10.1158/1538-7445.AM2017-LB-338
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2017
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...