Bioinformatics (Oxford, England), 2019
Authors
Nieuwoudt, Christina, Brooks-Wilson, Angela, Graham, Jinko
Publication Abstract
We present the R package SimRVSequences to simulate sequence data for pedigrees. SimRVSequences allows for simulations of large numbers of SNVs and scales well with increasing numbers of pedigrees. Users provide a sample of pedigrees and single-nucleotide variant data from a sample of unrelated individuals.

The Journal of pathology, 2019
Authors
Negri, Gian Luca, Grande, Bruno M, Delaidelli, Alberto, El-Naggar, Amal, Cochrane, Dawn, Lau, Ching C, Triche, Timothy J, Moore, Richard A, Jones, Steven Jm, Montpetit, Alexandre, Marra, Marco A, Malkin, David, Morin, Ryan D, Sorensen, Poul H
Publication Abstract
Despite being the most common childhood bone tumor, the genomic characterization of osteosarcoma remains incomplete. In particular, very few osteosarcoma metastases have been sequenced to date, critical to better understand mechanisms of progression and evolution in this tumor. We performed an integrated whole genome and exome sequencing analysis of paired primary and metastatic pediatric osteosarcoma specimens to identify recurrent genomic alterations. Sequencing of 13 osteosarcoma patients including 13 primary, 10 metastatic, and 3 locally recurring tumors revealed a highly heterogeneous mutational landscape, including cases of hypermutation and microsatellite instability positivity, but with virtually no recurrent alterations except for mutations involving the tumor suppressor genes RB1 and TP53. At the germline level, we detected alterations in multiple cancer related genes in the majority of the cohort, including those potentially disrupting DNA damage response pathways. Metastases retained only a minimal number of short variants from their corresponding primary tumors, while copy number alterations showed higher conservation. One recurrently amplified gene, KDR, was highly expressed in advanced cases and associated with poor prognosis. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Bioinformatics (Oxford, England), 2019
Authors
Jackman, Shaun D, Mozgacheva, Tatyana, Chen, Susie, O'Huiginn, Brendan, Bailey, Lance, Birol, Inanc, Jones, Steven J M
Publication Abstract
The ORCA bioinformatics environment is a Docker image that contains hundreds of bioinformatics tools and their dependencies. The ORCA image and accompanying server infrastructure provide a comprehensive bioinformatics environment for education and research. The ORCA environment on a server is implemented using Docker containers, but without requiring users to interact directly with Docker, suitable for novices who may not yet have familiarity with managing containers. ORCA has been used successfully to provide a private bioinformatics environment to external collaborators at a large genome institute, for teaching an undergraduate class on bioinformatics targeted at biologists, and to provide a ready-to-go bioinformatics suite for a hackathon. Using ORCA eliminates time that would be spent debugging software installation issues, so that time may be better spent on education and research.

Bioinformatics (Oxford, England), 2019
Authors
Warren, René L, Coombe, Lauren, Mohamadi, Hamid, Zhang, Jessica, Jaquish, Barry, Isabel, Nathalie, Jones, Steven J M, Bousquet, Jean, Bohlmann, Joerg, Birol, Inanç
Publication Abstract
In the modern genomics era, genome sequence assemblies are routine practice. However, depending on the methodology, resulting drafts may contain considerable base errors. Although utilities exist for genome base polishing, they work best with high read coverage and do not scale well. We developed ntEdit, a Bloom filter-based genome sequence editing utility that scales to large mammalian and conifer genomes.

Microbial genomics, 2019
Authors
Cochrane, Kyla, Robinson, Avery V, Holt, Robert A, Allen-Vercoe, Emma
Publication Abstract
Here, we report comprehensive transcriptomic profiles from under conditions that mimic the first stages of bacterial infection in a highly differentiated adenocarcinoma epithelial cell line. Our transcriptomic adenocarcinoma approach allows us to measure the expression dynamics and regulation of bacterial virulence and response factors in real time, and is a novel strategy for clarifying the role of infection in colorectal cancer (CRC) progression. Our data show that: (i) infection alters metabolic and functional pathways in , allowing the bacterium to adapt to the host-imposed milieu; (ii) infection also stimulates the expression of genes required to help induce and promote a hypoxic and inflammatory microenvironment in the host; and (iii) invasion occurs by a haematogenous route of infection. Our study identifies novel gene targets from that are activated during invasion and which may aid in determining how this species invades and promotes disease within the human gastrointestinal tract. These invasion-specific genes may be useful as biomarkers for CRC progression in a host and could also assist in the development of new diagnostic tools and treatments (such as vaccines or small molecule drug targets), which will be able to combat infection and inflammation in the host while circumventing the potential problem of tolerization.

Blood, 2019
Authors
Hilton, Laura K, Tang, Jeffrey, Ben-Neriah, Susana, Alcaide, Miguel, Jiang, Aixiang, Grande, Bruno M, Rushton, Christopher K, Boyle, Merrill, Meissner, Barbara, Scott, David W, Morin, Ryan D
Publication Abstract

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High-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements (HGBL-DH/THs) include a group of diffuse large B-cell lymphomas (DLBCLs) with inferior outcomes after standard chemoimmunotherapy. We recently described a gene expression signature that identifies 27% of germinal center B-cell DLBCLs (GCB-DLBCLs) as having a double-hit-like expression pattern (DHITsig) and inferior outcomes; however, only half of these cases have both MYC and BCL2 translocations identifiable using standard breakapart fluorescence in situ hybridization (FISH). Here, 20 DHITsig+ GCB-DLBCLs apparently lacking MYC and/or BCL2 rearrangements underwent whole-genome sequencing. This revealed 6 tumors with MYC or BCL2 rearrangements that were cryptic to breakapart FISH. Copy-number analysis identified 3 tumors with MYC and 6 tumors with MIR17HG gains or amplifications, both of which may contribute to dysregulation of MYC and its downstream pathways. Focal deletions of the PVT1 promoter were observed exclusively among DHITsig+ tumors lacking MYC translocations; this may also contribute to MYC overexpression. These results highlight that FISH fails to identify all HGBL-DH/THs, while revealing a range of other genetic mechanisms potentially underlying MYC dysregulation in DHITsig+ DLBCL, suggesting that gene expression profiling is more sensitive for identifying the biology underlying poor outcomes in GCB-DLBCL.

Nature communications, 2019
Authors
Sharma, Govinda, Rive, Craig M, Holt, Robert A
Publication Abstract

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Cytotoxic CD8+ T cells recognize and eliminate infected or malignant cells that present peptide epitopes derived from intracellularly processed antigens on their surface. However, comprehensive profiling of specific major histocompatibility complex (MHC)-bound peptide epitopes that are naturally processed and capable of eliciting a functional T cell response has been challenging. Here, we report a method for deep and unbiased T cell epitope profiling, using in vitro co-culture of CD8{{sup}}+{{/sup}} T cells together with target cells transduced with high-complexity, epitope-encoding minigene libraries. Target cells that are subject to cytotoxic attack from T cells in co-culture are isolated prior to apoptosis by fluorescence-activated cell sorting, and characterized by sequencing the encoded minigenes. We then validate this highly parallelized method using known murine T cell receptor/peptide-MHC pairs and diverse minigene-encoded epitope libraries. Our data thus suggest that this epitope profiling method allows unambiguous and sensitive identification of naturally processed and MHC-presented peptide epitopes.

Proceedings of the National Academy of Sciences of the United States of America, 2019
Authors
Shen, Yaoqing, Grisdale, Cameron J, Islam, Sumaiya A, Bose, Pinaki, Lever, Jake, Zhao, Eric Y, Grinshtein, Natalie, Ma, Yussanne, Mungall, Andrew J, Moore, Richard A, Lun, Xueqing, Senger, Donna L, Robbins, Stephen M, Wang, Alice Yijun, MacIsaac, Julia L, Kobor, Michael S, Luchman, H Artee, Weiss, Samuel, Chan, Jennifer A, Blough, Michael D, Kaplan, David R, Cairncross, J Gregory, Marra, Marco A, Jones, Steven J M
Publication Abstract
Glioblastoma multiforme (GBM) is the most deadly brain tumor, and currently lacks effective treatment options. Brain tumor-initiating cells (BTICs) and orthotopic xenografts are widely used in investigating GBM biology and new therapies for this aggressive disease. However, the genomic characteristics and molecular resemblance of these models to GBM tumors remain undetermined. We used massively parallel sequencing technology to decode the genomes and transcriptomes of BTICs and xenografts and their matched tumors in order to delineate the potential impacts of the distinct growth environments. Using data generated from whole-genome sequencing of 201 samples and RNA sequencing of 118 samples, we show that BTICs and xenografts resemble their parental tumor at the genomic level but differ at the mRNA expression and epigenomic levels, likely due to the different growth environment for each sample type. These findings suggest that a comprehensive genomic understanding of in vitro and in vivo GBM model systems is crucial for interpreting data from drug screens, and can help control for biases introduced by cell-culture conditions and the microenvironment in mouse models. We also found that lack of expression in pretreated GBM is linked to hypermutation, which in turn contributes to increased genomic heterogeneity and requires new strategies for GBM treatment.

Annual review of genomics and human genetics, 2019
Authors
Garrison, Nanibaa' A, Hudson, Māui, Ballantyne, Leah L, Garba, Ibrahim, Martinez, Andrew, Taualii, Maile, Arbour, Laura, Caron, Nadine R, Rainie, Stephanie Carroll
Publication Abstract
Indigenous scholars are leading initiatives to improve access to genetic and genomic research and health care based on their unique cultural contexts and within sovereign-based governance models created and accepted by their peoples. In the past, Indigenous peoples' engagement with genomicresearch was hampered by a lack of standardized guidelines and institutional partnerships, resulting in group harms. This article provides a comparative analysis of research guidelines from Canada, New Zealand, Australia, and the United States that pertain to Indigenous peoples. The goals of the analysis are to identify areas that need attention, support Indigenous-led governance, and promote the development of a model research policy framework for genomic research and health care that has international relevance for Indigenous peoples.

The journals of gerontology. Series A, Biological sciences and medical sciences, 2019
Authors
Tindale, Lauren C, Thiessen, Nina, Leach, Stephen, Brooks-Wilson, Angela R
Publication Abstract
The genetic basis of healthy aging and longevity remains largely unexplained. One hypothesis as to why long-lived individuals do not appear to have a lower number of common-complex disease variants, is that despite carrying risk variants, they express disease-linked alleles at a lower level than the wild-type alleles. Allele-specific abundance (ASA) is the different transcript abundance of the two haplotypes of a diploid individual. We sequenced the transcriptomes of four healthy centenarians and four mid-life controls. CIBERSORT was used to estimate blood cell fractions: neutrophils were the most abundant source of RNA, followed by CD8+ T cells, resting NK cells, and monocytes. ASA variants were more common in noncoding than coding regions. Centenarians and controls had a comparable distribution of ASA variants by predicted effect, and we did not observe an overall bias in expression toward major or minor alleles. Immune pathways were most highly represented among the gene set that showed ASA. Although we found evidence of ASA in disease-associated genes and transcription factors, we did not observe any differences in the pattern of expression between centenarians and controls in this small pilot study.
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