Karsan lab

The Karsan Lab focuses on two major areas: 

  1. Understanding the molecular basis of myeloid malignancies, in particular the preleukemic bone marrow failure conditions called myelodysplastic syndromes (MDS); and 
  2. Determining the role of the endothelium in the development of the hematopoietic system. With respect to both areas we have been studying the role of two pathways: innate immune signaling as represented by the Toll-like receptor (TLR) pathways, and the Notch signaling pathway.

Location

CRC

BC Cancer Research Centre
675 West 10th Avenue 
Vancouver, British Columbia 
V5Z 1L3 

Projects

Automation of the Clinical Bioinformatics Pipeline at the Centre for Clinical Genomics (Genome BC)

The aim of this project is to streamline the clinical bioinformatics pipeline by creating an automated and modular framework that will reduce training time, reduce reporting turnaround time, facilitate adaptation to new tools and changes to wet lab processes and reduce errors through tracking of information from the entire pipeline.

Development of an automated end-to-end next generation sequencing assay to detect all classes of genetic variant in a single diagnostic test

The aim of this project is to create a single genetic assay that will provide a comprehensive panel of cancer mutations required for both standard therapy and for patients to participate in cancer research.

The Terry Fox New Frontiers Program Project Grant in Exploiting Pathogenic Mechanisms in Acute Leukemia for Clinical Translation

The long term goal of this project is to better understand the difference between normal blood forming cells and leukemic cells. The lab aims to identify and exploit vulnerable disease causing pathways that may be shared across different types of acute leukemias.

Selected Publications

Effect of preexamination conditions in a centralized-testing model of non-invasive prenatal screening

Clinical Chemistry and Laboratory Medicine
Chad Fibke, Sylvie Giroux, André Caron, Elizabeth Starks, Jeremy DK Parker, Lucas Swanson, Loubna Jouan, Sylvie Langlois, Guy Rouleau, François Rousseau, Aly Karsan

Objectives: Non-invasive prenatal testing requires the presence of fetal DNA in maternal plasma. Understanding how preexamination conditions affect the integrity of cell-free DNA (cfDNA) and fetal fraction (FF) are a prerequisite for test implementation. Therefore, we examined the adjusted effect that EDTA and Streck tubes have on the cfDNA quantity and FF.

Methods: A total of 3,568 maternal blood samples across Canada were collected in either EDTA, or Streck tubes, and processing metrics, maternal body mass index (BMI), gestational age and fetal karyotype and sex were recorded. Plasma samples were sequenced using two different sequencing platforms in separate laboratories. Sequencing data were processed with SeqFF to estimate FF. Linear regression and multivariate imputation by chained equations were used to estimate the adjusted effect of tube type on cfDNA and FF.

Results: We found a positive association between cfDNA quantity and blood shipment time in EDTA tubes, which is significantly reduced with the use of Streck tubes. Furthermore, we show the storage of plasma at -80 °C is associated with a 4.4% annual relative decrease in cfDNA levels. FF was not associated with collection tube type when controlling for confounding variables. However, FF was positively associated with gestational age and trisomy 21, while negatively associated with BMI, male fetus, trisomy 18, Turners syndrome and triploidy.

Conclusions: Preexamination, maternal and fetal variables are associated with cfDNA quantity and FF. The consideration of these variables in future studies may help to reduce the number of pregnant women with inconclusive tests as a result of low FF.

Canadian ROS proto-oncogene 1 study (CROS) for multi-institutional implementation of ROS1 testing in non-small cell lung cancer

Lung Cancer
Carol C Cheung, Adam C Smith, Roula Albadine, Gilbert Bigras, Anna Bojarski, Christian Couture, Jean-Claude Cutz, Weei-Yuan Huang, Diana Ionescu, Doha Itani, Iyare Izevbaye, Aly Karsan, Margaret M Kelly, Joan Knoll, Keith Kwan, Michel R Nasr, Gefei Qing, Fariboz Rashid-Kolvear, Harmanjatinder S Sekhon, Alan Spatz, Tracy Stockley, Danh Tran-Thanh, Tracy Tucker, Ranjit Waghray, Hangjun Wang, Zhaolin Xu, Yasushi Yatabe, Emina E Torlakovic, Ming-Sound Tsao

Patients with non-small cell lung cancer (NSCLC) harboring ROS proto-oncogene 1 (ROS1) gene rearrangements show dramatic response to the tyrosine kinase inhibitor (TKI) crizotinib. Current best practice guidelines recommend that all advanced stage non-squamous NSCLC patients be also tested for ROS1 gene rearrangements. Several studies have suggested that ROS1 immunohistochemistry (IHC) using the D4D6 antibody may be used to screen for ROS1 fusion positive lung cancers, with assays showing high sensitivity but moderate to high specificity. A break apart fluorescence in situ hybridization (FISH) test is then used to confirm the presence of ROS1 gene rearrangement. The goal of Canadian ROS1 (CROS) study was to harmonize ROS1 laboratory developed testing (LDT) by using IHC and FISH assays to detect ROS1 rearranged lung cancers across Canadian pathology laboratories. Cell lines expressing different levels of ROS1 (high, low, none) were used to calibrate IHC protocols after which participating laboratories ran the calibrated protocols on a reference set of 24 NSCLC cases (9 ROS1 rearranged tumors and 15 ROS1 non-rearranged tumors as determined by FISH). Results were compared using a centralized readout. The stained slides were evaluated for the cellular localization of staining, intensity of staining, the presence of staining in non-tumor cells, the presence of non-specific staining (e.g. necrosis, extracellular mater, other) and the percent positive cells. H-score was also determined for each tumor. Analytical sensitivity and specificity harmonization was achieved by using low limit of detection (LOD) as either any positivity in the U118 cell line or H-score of 200 with the HCC78 cell line. An overall diagnostic sensitivity and specificity of up to 100% and 99% respectively was achieved for ROS1 IHC testing (relative to FISH) using an adjusted H-score readout on the reference cases. This study confirms that LDT ROS1 IHC assays can be highly sensitive and specific for detection of ROS1 rearrangements in NSCLC. As NSCLC can demonstrate ROS1 IHC positivity in FISH-negative cases, the degree of the specificity of the IHC assay, especially in highly sensitive protocols, is mostly dependent on the readout cut-off threshold. As ROS1 IHC is a screening assay for a rare rearrangements in NSCLC, we recommend adjustment of the readout threshold in order to balance specificity, rather than decreasing the overall analytical and diagnostic sensitivity of the protocols.

Use of Treatment-Focused Tumor Sequencing to Screen for Germline Cancer Predisposition

The Journal of Molecular Diagnostics
Tammy TY Lau, Christina M May, Zahra J Sefid Dashti, Lucas Swanson, Elizabeth R Starks, Jeremy DK Parker, Richard A Moore, Tracy Tucker, Ian Bosdet, Sean S Young, Jennifer L Santos, Katie Compton, Nili Heidary, Lien Hoang, Kasmintan A Schrader, Sophie Sun, Janice S Kwon, Anna V Tinker, Aly Karsan

Next-generation sequencing assays are capable of identifying cancer patients eligible for targeted therapies and can also detect germline variants associated with increased cancer susceptibility. However, these capabilities have yet to be routinely harmonized in a single assay because of challenges with accurately identifying germline variants from tumor-only data. We have developed the Oncology and Hereditary Cancer Program targeted capture panel, which uses tumor tissue to simultaneously screen for both clinically actionable solid tumor variants and germline variants across 45 genes. Validation using 14 tumor specimens, composed of patient samples and cell lines analyzed in triplicate, demonstrated high coverage with sensitive and specific identification of single-nucleotide variants and small insertions and deletions. Average coverage across all targets remained >2000× in 198 additional patient tumor samples. Analysis of 55 formalin-fixed, paraffin-embedded tumor samples for the detection of known germline variants within a subset of cancer-predisposition genes, including one multiexon deletion, yielded a 100% detection rate, demonstrating that germline variants can be reliably detected in tumor samples using a single panel. Combining targetable somatic and actionable germline variants into a single tumor tissue assay represents a streamlined approach that can inform treatment for patients with advanced cancers as well as identify those with potential germline variants who are eligible for confirmatory testing, but would not otherwise have been identified.

A clinical transcriptome approach to patient stratification and therapy selection in acute myeloid leukemia

Nature Communications, 2021
T Roderick Docking, Jeremy D K Parker, Martin Jädersten, Gerben Duns, Linda Chang, Jihong Jiang, Jessica A Pilsworth, Lucas A Swanson, Simon K Chan, Readman Chiu, Ka Ming Nip, Samantha Mar, Angela Mo, Xuan Wang, Sergio Martinez-Høyer, Ryan J Stubbins, Karen L Mungall, Andrew J Mungall, Richard A Moore, Steven J M Jones, İnanç Birol, Marco A Marra, Donna Hogge, Aly Karsan

As more clinically-relevant genomic features of myeloid malignancies are revealed, it has become clear that targeted clinical genetic testing is inadequate for risk stratification. Here, we develop and validate a clinical transcriptome-based assay for stratification of acute myeloid leukemia (AML). Comparison of ribonucleic acid sequencing (RNA-Seq) to whole genome and exome sequencing reveals that a standalone RNA-Seq assay offers the greatest diagnostic return, enabling identification of expressed gene fusions, single nucleotide and short insertion/deletion variants, and whole-transcriptome expression information. Expression data from 154 AML patients are used to develop a novel AML prognostic score, which is strongly associated with patient outcomes across 620 patients from three independent cohorts, and 42 patients from a prospective cohort. When combined with molecular risk guidelines, the risk score allows for the re-stratification of 22.1 to 25.3% of AML patients from three independent cohorts into correct risk groups. Within the adverse-risk subgroup, we identify a subset of patients characterized by dysregulated integrin signaling and RUNX1 or TP53 mutation. We show that these patients may benefit from therapy with inhibitors of focal adhesion kinase, encoded by PTK2, demonstrating additional utility of transcriptome-based testing for therapy selection in myeloid malignancy.

Germline testing and somatic tumor testing for BRCA1/2 pathogenic variants in ovarian cancer: What is the optimal sequence of testing?

Journal of Clinical Oncology
Janice S Kwon, Anna Tinker, Jennifer Santos, Katie Compton, Sophie Sun, Kasmintan A Schrader, Aly Karsan

Background: In 2020 ASCO recommended that all women with epithelial ovarian cancer have germline testing (GT) for BRCA1/2 mutations, and those without a germline pathogenic variant (PV) should have somatic tumor testing (TT), to determine eligibility for PARP inhibitor (PARPi) therapy (GT-TT strategy). An alternate strategy is to start with tumor testing first, and to conduct germline testing only in those with a PV in the tumor, or a significant family history (TT-GT strategy). The objective was to conduct a cost-effectiveness analysis comparing the 2 testing strategies. Methods: A Markov Monte Carlo simulation model compared the costs (USD) and benefits of the 2 testing strategies. According to local empiric data, a sufficient tissue sample for TT was available in 99% of cases, otherwise the patient would only have GT. Sensitivity of TT was 99% for detecting germline PV. Only those with BRCA1/2 PV were eligible for PARPi. Primary outcomes included the number of women eligible for PARPi, with progression-free years of life (PFLY) gained based on SOLO1 data, and the incremental cost-effectiveness ratio (ICER). Monte Carlo simulation estimated the number of women who would have GT and TT, and the total with germline or somatic BRCA1/2 PV eligible for PARPi. Sensitivity analyses accounted for uncertainty around various parameters. Results: The GT-TT strategy was more effective but more costly than TT-GT in identifying patients eligible for PARPi. Table summarizes the average lifetime costs, benefits, and Monte Carlo simulation estimates for 10,000 women diagnosed with advanced epithelial ovarian cancer annually in the USA. The incremental benefit from the GT-TT strategy would be achieved at substantial cost to the health care system, with an ICER of $119,340 per PFLY gained relative to the TT-GT strategy. The results were highly sensitive to the sensitivity of TT to detect germline PV, and the costs of GT and TT. Assuming that GT was less than 50% of the cost of TT, the sensitivity of TT had to exceed 98% for the TT-GT strategy to be cost-effective. Conclusions: Although the ASCO recommended strategy of BRCA germline testing followed by tumor testing for those without a pathogenic variant may be more effective in identifying ovarian cancer patients for PARP inhibitor therapy, it is more costly. The ASCO strategy is justified if the sensitivity of tumor testing is not sufficiently high. However, assuming high tumor testing performance rates, tumor testing first followed by germline testing if there is a PV in the tumor and/or family history is a cost-effective strategy.

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MET exon 14 skipping mutation positive non-small cell lung cancer: Response to systemic therapy

Lung Cancer
Selina K Wong, Deepu Alex, Ian Bosdet, Curtis Hughesman, Aly Karsan, Stephen Yip, Cheryl Ho

Objectives: MET exon 14 skipping is a potentially targetable molecular alteration. The goals of this study were to identify patients treated in British Columbia with MET exon 14 skipping to understand prevalence, biology and response to treatment, and to identify molecular signatures that may predict for response or resistance to targeted MET therapy in the setting of advanced disease.

Materials and methods: A retrospective review was completed of patients found to have MET exon 14 skipping alterations between January 2016-September 2019. Information was collected on baseline characteristics, response to systemic treatments, and outcomes.

Results: Out of 1934 advanced, non-squamous and never-smoking squamous NSCLC patients tested, 41 patients were found to have MET exon 14 skipping (2.1 %). MET alteration types: 2% CBL binding-domain mutations, 34 % poly-pyrimidine tract deletions, 63 % splice donor mutations or deletions. The most common co-mutation was TP53 (22 %). Thirty-three patients received systemic therapy. Physician-assessed disease control was 68 % among 19 evaluable patients treated with crizotinib, 80 % among 10 evaluable patients treated with platinum-based chemotherapy, and 70 % among 10 evaluable patients treated with immunotherapy. Median time to treatment discontinuation was 3.0, 2.8, and 2.4 months, respectively. Median overall survival for metastatic patients treated with any systemic therapy was 15.4 months. In this small cohort, there were no clear correlations between molecular aberrations and response, time to treatment discontinuation, or survival for crizotinib, chemotherapy, and immunotherapy.

Conclusion: The prevalence of MET exon 14 skipping in a North American population was 2.1 %. Unlike other targetable mutations, patients were older and more commonly current or former smokers. Patients with MET exon 14 skipping alteration demonstrate disease control with crizotinib, platinum-based chemotherapy and immunotherapy. Co-mutations with TP53 were commonly noted, but correlation between co-mutations and efficacy of therapy were not identified in this cohort.

Colorectal Cancer Detection Based on Deep Learning

Journal of Pathology Informatics
Lin Xu, Blair Walker, Peir-In Liang, Yi Tong, Cheng Xu, Yu Chun Su, Aly Karsan

Introduction: The initial point in the diagnostic workup of solid tumors remains manual, with the assessment of hematoxylin and eosin (H&E)-stained tissue sections by microscopy. This is a labor-intensive step that requires attention to detail. In addition, diagnoses are influenced by an individual pathologist's knowledge and experience and may not always be reproducible between pathologists. Methods: We introduce a deep learning-based method in colorectal cancer detection and segmentation from digitized H&E-stained histology slides. Results: In this study, we demonstrate that this neural network approach produces median accuracy of 99.9% for normal slides and 94.8% for cancer slides compared to pathologist-based diagnosis on H&E-stained slides digitized from clinical samples. Conclusion: Given that our approach has very high accuracy on normal slides, use of neural network algorithms may provide a screening approach to save pathologist time in identifying tumor regions. We suggest that this new method may be a powerful assistant for colorectal cancer diagnostics.

Quality of life and socioeconomic indicators associated with survival of myeloid leukemias in Canada

eJHaem
Sonya Cressman, Donna E Hogge, Mark D Minden,Stephen Couban, Aly Karsan, Raewyn Broady, Emily McPherson, Khalif Halani, Jing Yi Weng, Stuart J Peacock

Understanding how patient-reported quality of life (QoL) and socioeconomic status (SES) relate to survival of acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) may improve prognostic information sharing. This study explores associations among QoL, SES, and survival through administration of the Euro-QoL 5-Dimension, 3-level and Functional Assessment of Cancer Therapy-Leukemia and financial impact questionnaires to 138 adult participants with newly diagnosed AML or MDS in a longitudinal, pan-Canadian study. Cox regression and lasso variable selection models were used to explore associations among QoL, SES, and established predictors of survival. Secondary outcomes were changes in QoL, performance of the QoL instruments, and lost income. We found that higher QoL and SES were positively associated with survival. The Lasso model selected the visual analog scale of the EQ-5D-3L as the most important predictor among all other variables (P = .03; 92% selection). Patients with AML report improved QoL after treatment, despite higher mean out-of-pocket expenditures compared with MDS (up to $599 CDN/month for AML vs $239 for MDS; P = .05), greater loss of productivity-related income (reaching $1786/month for AML vs $709 for MDS; P < .05), and greater caregiver effects (65% vs 35% caregiver productivity losses for AML vs MDS; P < .05). Our results suggest that including patient-reported QoL and socioeconomic indicators can improve the accuracy of survival models.

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Multicenter validation study to implement plasma epidermal growth factor receptor T790M testing in clinical laboratories

JCO Precision Oncology
Natasha B Leighl, Suzanne Kamel-Reid, Parneet K Cheema, Janessa Laskin, Aly Karsan, Tong Zhang, Tracy Stockley, Tristan A Barnes, Roxana A Tudor, Geoffrey Liu, Scott Owen, Jeffrey Rothenstein, Ronald L Burkes, Mussawar Iqbal, Alan Spatz, Léon C van Kempen, Iyare Izevbaye, David Laurence, Lisa W Le, Ming-Sound Tsao

PURPOSE

Plasma detection of EGFR T790M mutations is an emerging alternative to tumor rebiopsy in acquired epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor resistance. Validation of analytical sensitivity and clinical utility is required before routine diagnostic use in clinical laboratories.

PATIENTS AND METHODS

Sixty-three patients with advanced EGFR-mutant lung cancer at 7 Canadian centers, who were being screened for the ASTRIS trial (ClinicalTrials.gov identifier: NCT02474355), participated in this companion study. Plasma T790M mutation was detected using droplet digital polymerase chain reaction, Cobas (Roche Diagnostics, Indianapolis, IN), or next-generation sequencing in 4 laboratories. T790M concordance was assessed between plasma and tumor samples.

RESULTS

Assessment of T790M in tumor biopsy tissue was successful in 81% of patients; 49% had confirmed T790M results (tumor or plasma) for ASTRIS. Plasma testing in this companion study yielded T790M results in 97% of patients; 62% had T790M-positive results, 36% had negative results, and 2% had indeterminate results. Of 38 patients with negative or indeterminate biopsy results, 55% had positive plasma T790M results, increasing the proportion with T790M-positive results to 73%. Sensitivity of plasma T790M testing was 75%. Overall concordance between tissue and plasma was 64%, and concordance among laboratories was 90.3%. Response to osimertinib and duration of therapy were similar irrespective of testing method (overall response rate, 62.5% for tissue, 66.7% for plasma, and 70.6% for both).

CONCLUSION

This multicenter validation study demonstrates that plasma EGFR T790M testing can identify significantly more patients than biopsy alone who may benefit from targeted therapy.

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Loss of lenalidomide-induced megakaryocytic differentiation leads to therapy resistance in del(5q) myelodysplastic syndrome.

Nature cell biology, 2020
Martinez-Høyer, Sergio, Deng, Yu, Parker, Jeremy, Jiang, Jihong, Mo, Angela, Docking, T Roderick, Gharaee, Nadia, Li, Jenny, Umlandt, Patricia, Fuller, Megan, Jädersten, Martin, Kulasekararaj, Austin, Malcovati, Luca, List, Alan F, Hellström-Lindberg, Eva, Platzbecker, Uwe, Karsan, Aly
Interstitial deletion of the long arm of chromosome 5 (del(5q)) is the most common structural genomic variant in myelodysplastic syndromes (MDS){{sup}}1{{/sup}}. Lenalidomide (LEN) is the treatment of choice for patients with del(5q) MDS, but half of the responding patients become resistant{{sup}}2{{/sup}} within 2 years. TP53 mutations are detected in ~20% of LEN-resistant patients{{sup}}3{{/sup}}. Here we show that patients who become resistant to LEN harbour recurrent variants of TP53 or RUNX1. LEN upregulated RUNX1 protein and function in a CRBN- and TP53-dependent manner in del(5q) cells, and mutation or downregulation of RUNX1 rendered cells resistant to LEN. LEN induced megakaryocytic differentiation of del(5q) cells followed by cell death that was dependent on calpain activation and CSNK1A1 degradation{{sup}}4,5{{/sup}}. We also identified GATA2 as a LEN-responsive gene that is required for LEN-induced megakaryocyte differentiation. Megakaryocytic gene-promoter analyses suggested that LEN-induced degradation of IKZF1 enables a RUNX1-GATA2 complex to drive megakaryocytic differentiation. Overexpression of GATA2 restored LEN sensitivity in the context of RUNX1 or TP53 mutations by enhancing LEN-induced megakaryocytic differentiation. Screening for mutations that block LEN-induced megakaryocytic differentiation should identify patients who are resistant to LEN.

Sample Tracking Using Unique Sequence Controls.

The Journal of molecular diagnostics : JMD, 2020
Moore, Richard A, Zeng, Thomas, Docking, T Roderick, Bosdet, Ian, Butterfield, Yaron S, Munro, Sarah, Li, Irene, Swanson, Lucas, Starks, Elizabeth R, Tse, Kane, Mungall, Andrew J, Holt, Robert A, Karsan, Aly
Sample tracking and identity are essential when processing multiple samples in parallel. Sequencing applications often involve high sample numbers, and the data are frequently used in a clinical setting. As such, a simple and accurate intrinsic sample tracking process through a sequencing pipeline is essential. Various solutions have been implemented to verify sample identity, including variant detection at the start and end of the pipeline using arrays or genotyping, bioinformatic comparisons, and optical barcoding of samples. None of these approaches are optimal. To establish a more effective approach using genetic barcoding, we developed a panel of unique DNA sequences cloned into a common vector. A unique DNA sequence is added to the sample when it is first received and can be detected by PCR and/or sequencing at any stage of the process. The control sequences are approximately 200 bases long with low identity to any sequence in the National Center for Biotechnology Information nonredundant database (<30 bases) and contain no long homopolymer (>7) stretches. When a spiked next-generation sequencing library is sequenced, sequence reads derived from this control sequence are generated along with the standard sequencing run and are used to confirm sample identity and determine cross-contamination levels. This approach is used in our targeted clinical diagnostic whole-genome and RNA-sequencing pipelines and is an inexpensive, flexible, and platform-agnostic solution.

Fixation Effects on Variant Calling in a Clinical Resequencing Panel.

The Journal of molecular diagnostics : JMD, 2019
Parker, Jeremy D K, Yap, Shyong Quin, Starks, Elizabeth, Slind, Jillian, Swanson, Lucas, Docking, T Roderick, Fuller, Megan, Zhou, Chen, Walker, Blair, Filipenko, Douglas, Xiong, Wei, Karimuddin, Ahmer A, Phang, P Terry, Raval, Manoj, Brown, Carl J, Karsan, Aly
Formalin fixation is the standard method for the preservation of tissue for diagnostic purposes, including pathologic review and molecular assays. However, this method is known to cause artifacts that can affect the accuracy of molecular genetic test results. We assessed the applicability of alternative fixatives to determine whether these perform significantly better on next-generation sequencing assays, and whether adequate morphology is retained for primary diagnosis, in a prospective study using a clinical-grade, laboratory-developed targeted resequencing assay. Several parameters relating to sequencing quality and variant calling were examined and quantified in tumor and normal colon epithelial tissues. We identified an alternative fixative that suppresses many formalin-related artifacts while retaining adequate morphology for pathologic review.

Endothelial Sash1 Is Required for Lung Maturation through Nitric Oxide Signaling.

Cell reports, 2019
Coulombe, Patrick, Paliouras, Grigorios N, Clayton, Ashley, Hussainkhel, Angela, Fuller, Megan, Jovanovic, Vida, Dauphinee, Shauna, Umlandt, Patricia, Xiang, Ping, Kyle, Alistair H, Minchinton, Andrew I, Humphries, R Keith, Hoodless, Pamela A, Parker, Jeremy D K, Wright, Joanne L, Karsan, Aly
The sterile alpha motif (SAM) and SRC homology 3 (SH3) domain containing protein 1 (Sash1) acts as a scaffold in TLR4 signaling. We generated Sash1{{sup}}-/-{{/sup}} mice, which die in the perinatal period due to respiratory distress. Constitutive or endothelial-restricted Sash1 loss leads to a delay in maturation of alveolar epithelial cells causing reduced surfactant-associated protein synthesis. We show that Sash1 interacts with β-arrestin 1 downstream of the TLR4 pathway to activate Akt and endothelial nitric oxide synthase (eNOS) in microvascular endothelial cells. Generation of nitric oxide downstream of Sash1 in endothelial cells affects alveolar epithelial cells in a cGMP-dependent manner, inducing maturation of alveolar type 1 and 2 cells. Thus, we identify a critical cell nonautonomous function for Sash1 in embryonic development in which endothelial Sash1 regulates alveolar epithelial cell maturation and promotes pulmonary surfactant production through nitric oxide signaling. Lung immaturity is a major cause of respiratory distress and mortality in preterm infants, and these findings identify the endothelium as a potential target for therapy.

Genomic testing in myeloid malignancy.

International journal of laboratory hematology, 2019
Docking, T Roderick, Karsan, Aly
Clinical genetic testing in the myeloid malignancies is undergoing a rapid transition from the era of cytogenetics and single-gene testing to an era dominated by next-generation sequencing (NGS). This transition promises to better reveal the genetic alterations underlying disease, but there are distinct risks and benefits associated with different NGS testing platforms. NGS offers the potential benefit of being able to survey alterations across a wider set of genes, but analytic and clinical challenges associated with incidental findings, germ line variation, turnaround time, and limits of detection must be addressed. Additionally, transcriptome-based testing may offer several distinct benefits beyond traditional DNA-based methods. In addition to testing at disease diagnosis, research indicates potential benefits of genetic testing both prior to disease onset and at remission. In this review, we discuss the transition from the era of cytogenetics and single-gene tests to the era of NGS panels and genome-wide sequencing-highlighting both the potential and drawbacks of these novel technologies.

miR-143/145 differentially regulate hematopoietic stem and progenitor activity through suppression of canonical TGFβ signaling.

Nature communications, 2018
Lam, Jeffrey, van den Bosch, Marion, Wegrzyn, Joanna, Parker, Jeremy, Ibrahim, Rawa, Slowski, Kate, Chang, Linda, Martinez-Høyer, Sergio, Condorelli, Gianluigi, Boldin, Mark, Deng, Yu, Umlandt, Patricia, Fuller, Megan, Karsan, Aly
Expression of miR-143 and miR-145 is reduced in hematopoietic stem/progenitor cells (HSPCs) of myelodysplastic syndrome patients with a deletion in the long arm of chromosome 5. Here we show that mice lacking miR-143/145 have impaired HSPC activity with depletion of functional hematopoietic stem cells (HSCs), but activation of progenitor cells (HPCs). We identify components of the transforming growth factor β (TGFβ) pathway as key targets of miR-143/145. Enforced expression of the TGFβ adaptor protein and miR-145 target, Disabled-2 (DAB2), recapitulates the HSC defect seen in miR-143/145{{sup}}-/-{{/sup}} mice. Despite reduced HSC activity, older miR-143/145{{sup}}-/-{{/sup}} and DAB2-expressing mice show elevated leukocyte counts associated with increased HPC activity. A subset of mice develop a serially transplantable myeloid malignancy, associated with expansion of HPC. Thus, miR-143/145 play a cell context-dependent role in HSPC function through regulation of TGFβ/DAB2 activation, and loss of these miRNAs creates a preleukemic state.

Applications of Bayesian network models in predicting types of hematological malignancies.

Scientific reports, 2018
Agrahari, Rupesh, Foroushani, Amir, Docking, T Roderick, Chang, Linda, Duns, Gerben, Hudoba, Monika, Karsan, Aly, Zare, Habil
Network analysis is the preferred approach for the detection of subtle but coordinated changes in expression of an interacting and related set of genes. We introduce a novel method based on the analyses of coexpression networks and Bayesian networks, and we use this new method to classify two types of hematological malignancies; namely, acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). Our classifier has an accuracy of 93%, a precision of 98%, and a recall of 90% on the training dataset (n = 366); which outperforms the results reported by other scholars on the same dataset. Although our training dataset consists of microarray data, our model has a remarkable performance on the RNA-Seq test dataset (n = 74, accuracy = 89%, precision = 88%, recall = 98%), which confirms that eigengenes are robust with respect to expression profiling technology. These signatures are useful in classification and correctly predicting the diagnosis. They might also provide valuable information about the underlying biology of diseases. Our network analysis approach is generalizable and can be useful for classifying other diseases based on gene expression profiles. Our previously published Pigengene package is publicly available through Bioconductor, which can be used to conveniently fit a Bayesian network to gene expression data.

Identification of miR-145 and miR-146a as mediators of the 5q- syndrome phenotype.

Nature medicine, 2010
Starczynowski, Daniel T, Kuchenbauer, Florian, Argiropoulos, Bob, Sung, Sandy, Morin, Ryan, Muranyi, Andrew, Hirst, Martin, Hogge, Donna, Marra, Marco, Wells, Richard A, Buckstein, Rena, Lam, Wan, Humphries, R Keith, Karsan, Aly
5q- syndrome is a subtype of myelodysplastic syndrome characterized by severe anemia and variable neutropenia but normal or high platelet counts with dysplastic megakaryocytes. We examined expression of microRNAs (miRNAs) encoded on chromosome 5q as a possible cause of haploinsufficiency. We show that deletion of chromosome 5q correlates with loss of two miRNAs that are abundant in hematopoietic stem/progenitor cells (HSPCs), miR-145 and miR-146a, and we identify Toll-interleukin-1 receptor domain-containing adaptor protein (TIRAP) and tumor necrosis factor receptor-associated factor-6 (TRAF6) as respective targets of these miRNAs. TIRAP is known to lie upstream of TRAF6 in innate immune signaling. Knockdown of miR-145 and miR-146a together or enforced expression of TRAF6 in mouse HSPCs resulted in thrombocytosis, mild neutropenia and megakaryocytic dysplasia. A subset of mice transplanted with TRAF6-expressing marrow progressed either to marrow failure or acute myeloid leukemia. Thus, inappropriate activation of innate immune signals in HSPCs phenocopies several clinical features of 5q- syndrome.

Jagged1-mediated Notch activation induces epithelial-to-mesenchymal transition through Slug-induced repression of E-cadherin.

The Journal of experimental medicine, 2007
Leong, Kevin G, Niessen, Kyle, Kulic, Iva, Raouf, Afshin, Eaves, Connie, Pollet, Ingrid, Karsan, Aly
Aberrant expression of Jagged1 and Notch1 are associated with poor outcome in breast cancer. However, the reason that Jagged1 and/or Notch overexpression portends a poor prognosis is unknown. We identify Slug, a transcriptional repressor, as a novel Notch target and show that elevated levels of Slug correlate with increased expression of Jagged1 in various human cancers. Slug was essential for Notch-mediated repression of E-cadherin, which resulted in beta-catenin activation and resistance to anoikis. Inhibition of ligand-induced Notch signaling in xenografted Slug-positive/E-cadherin-negative breast tumors promoted apoptosis and inhibited tumor growth and metastasis. This response was associated with down-regulated Slug expression, reexpression of E-cadherin, and suppression of active beta-catenin. Our findings suggest that ligand-induced Notch activation, through the induction of Slug, promotes tumor growth and metastasis characterized by epithelial-to-mesenchymal transition and inhibition of anoikis.

Recent insights into the role of Notch signaling in tumorigenesis.

Blood, 2006
Leong, Kevin G, Karsan, Aly
Members of the Notch family of transmembrane receptors play an important role in cell fate determination. Over the past decade, a role for Notch in the pathogenesis of hematologic and solid malignancies has become apparent. Numerous cellular functions and microenvironmental cues associated with tumorigenesis are modulated by Notch signaling, including proliferation, apoptosis, adhesion, epithelial-to-mesenchymal transition, and angiogenesis. It is becoming increasingly evident that Notch signaling can be both oncogenic and tumor suppressive. This review highlights recent findings regarding the molecular and functional aspects of Notch-mediated neoplastic transformation. In addition, cellular mechanisms that potentially explain the complex role of Notch in tumorigenesis are discussed.

Staff

Dr. Joshua Bridgers

Staff Scientist

Dr. Christina May

Research Associate

Chad Fibke

Research Programmer

Sue Huang

Research Programmer

Harwood Kwan

Research Programmer

Tammy Lau

Research Programmer

Elijah Willie

Research Programmer

Deborah Deng

Research Assistant

Jihong Jiang

Research Assistant

Jessica Tran

Research Assistant

Patrick Lac

Graduate Student

Lemlem Degefie

Laboratory Assistant

Postdoctoral Fellows

Dr. Vijay Suresh Akhade

Postdoctoral Fellow

Dr. Grace Cole

Postdoctoral Fellow

Dr. Jennifer Grants

Postdoctoral Fellow

Dr. Patrick Coulombe

Postdoctoral Fellow

Trainees

Nadia Gharaee

Graduate Student

Aparna Gopal

Graduate Student

Hayle Kincross

Graduate Student

Angela Mo

Graduate Student

Ryan Stubbins

Graduate Student

Derek Tam

Graduate Student

Open Positions

Research Programmer - Data Scientist

Canada’s Michael Smith Genome Sciences Centre (GSC)

Today’s Research. Tomorrow’s Medicine.

The GSC is a department of the BC Cancer Research Institute and a high-throughput genome sequencing facility. We are leaders in genomics, proteomics and bioinformatics in pursuit of novel treatment strategies for cancers and other diseases.

Among the world’s first genome centres to be established within a cancer clinic, for more than two decades our scientists and innovators have been designing and deploying cutting-edge technologies to benefit health and advance clinical research.

Among the GSC’s most significant accomplishments are the first publication to demonstrate the use of whole-genome sequencing to inform cancer treatment planning, the first published sequence of the SARS coronavirus genome and major contributions to the first physical map of the human genome as part of the Human Genome Project.

By joining the GSC you will become part of an exceptional and diverse team of scientists, clinicians, experts and professionals operating at the leading edge of clinical research. We look for people who share our core values—science, timeliness, respect—to join us on our mission to use genome science for the betterment of health and society.

Summary

Job Reference No: RP_R00008_Karssan Lab_ 2021_05_19

Dr. Aly Karsan and the Karsan lab team at Genome Sciences Centre (GSC) are seeking a Research Programmer to join a Marathon of Hope Cancer Centre research project. The team will be working with other research programmers at the Karsan lab for developing data analysis pipelines for various next-generation sequencing (NGS) data such as but not limited to scRNA-Seq, targeted sequencing, ATAC-Seq, and BS-Seq, for the study of cancer evolution. We seek candidates with strong analytical and programming skills to research, develop, and improve our research pipelines.

The role is ideally suited for detail-oriented individuals with a strong interest in data analysis, research, and scientific programming within a high throughput academic setting.  The Karsan lab has a history of strong publications and can offer great experience in research with full access to the GSC’s world-class compute cluster.  Additionally, the Karsan Lab has a diverse computational biology core for knowledge sharing, collaboration, and support. 

Duties/Accountabilities

  • Design and implement bioinformatic data pipelines to meet objectives of the project
  • Work with other project team members to develop and test code, and implement analysis
  • Evaluate and incorporate third-party software into pipelines
  • Produce thorough but concise written documentation of experiments, algorithms, validations, and other procedures as required.

 Qualifications

  • Graduation from a recognized Bachelor of Science Program in Computer Science or relevant program. A Master’s degree in a relevant field would be a strong asset. 
  • Two (2) years of recent related experience or an equivalent combination of education, training, and experience.

Core Skills and Abilities

  • Expertise with scientific programming and able to provide links to code samples via GitHub
  • Familiarity with molecular and cellular biology
  • Excellent verbal and written communication skills
  • Demonstrated ability to interpret results
  • Comfortable working in a Unix environment, including experience with shell scripting and common command-line tools
  • Established ability to efficiently organize work assignments and establish priorities
  • Demonstrated interpersonal skills including the ability to work effectively with others in a team environment.

Additional Assets

  • Familiarity in statistical analysis using modern computational tools (experience with any relevant tools will be considered, but R and Python are preferred)
  • Familiarity in next-generation sequencing datasets
  • Understanding of cancer biology
  • Functional knowledge of distributed version control systems, such as SVN or GIT

Apply

Please submit a detailed cover letter and resume to bcgscjobs@bcgsc.ca, using Job Reference No: RP_R00008_Karssan Lab_ 2021_05_19 in the subject line of your email.

This posting will remain online until filled.

Important!

Due to current COVID-19 restrictions, the position would require working remotely within British Columbia on a temporary basis with an ability to come to the normal workplace within reasonable notice. This restriction would be re-evaluated after finalization of reopening plans.

As per the current Public Health Order, full vaccination against COVID-19 is a condition of employment with PHSA as of October 26, 2021.

We believe that diversity and inclusivity are essential for the advancement of human knowledge and science.

We welcome all applicants and provide all employees with equal opportunity for advancement, regardless of race, colour, ancestry, place of origin, political belief, religion, marital status, family status, physical or mental disability, sex, sexual orientation, gender identity or expression, age, conviction of a criminal or summary conviction offence unrelated to their employment.

All qualified candidates are encouraged to apply; however, Canadian citizens and permanent residents will be given priority.

Research Programmer

About us
Canada's Michael Smith Genome Sciences Centre (GSC) at BC Cancer is an international leader in genomics, proteomics, and bioinformatics for precision medicine. By developing and deploying genome sequencing, computational and analytical technology, we are creating novel strategies to prevent and diagnose cancers and other diseases, uncovering new therapeutic targets, and helping the world realize the social and economic benefits of genome science

Learn more about how the GSC is Bringing Genomics to Life.

Why work at the GSC
As the first genome centre to be established within a cancer clinic, our story began by thinking outside of the box. From being the first in the world to sequence the SARS coronavirus during the 2003 global outbreak to publishing the first study demonstrating the use of whole-genome sequencing to influence personalized cancer treatment planning in 2010, our passion for pushing scientific frontiers continues to this day.

Our technology platforms enable the transformative science being done at the GSC, but it is our world-class team of scientists and innovators that make it happen. By joining the GSC you will become part of a diverse and dedicated group of biologists, bioinformaticians, computer scientists, computational biologists, biochemists, engineers, and clinicians. We look for people who share our core values—science, timeliness, and respect—to join us in our mission to provide genomics, bioinformatics, and proteomics technology and expertise for the benefit of human health and society.


Job Reference No.: RP_R00008_Karsan Lab_2021_04_19

Role Summary

The Karsan lab team at Canada’s Michael Smith Genome Sciences Centre (GSC) is seeking a research programmer to join a Genome British Columbia software automation project. The team will be working with the Karsan lab, which is responsible for developing high-throughput, clinically accredited pipelines to analyse sequenced data from genomic assays for individualized patient management of cancer. We seek candidates with strong Python software and programming skills to automate and improve existing pipelines and potentially incorporate third-party software into the system.

The role is ideally suited for a creative individual with a strong interest in software development and testing, data analysis, and automation within a high throughput academic setting.

Key responsibilities

  • Design, plan, and implement automated bioinformatics pipelines to meet the objectives of the project
  • Work with other project team members to develop and test code, and implement software
  • Evaluate third-party software and incorporate new systems into legacy systems
  • Produce thorough but concise written documentation of algorithms, validations, SOPs, and other processes and procedures as required

Qualifications

Education, training and experience

  • Graduation from a recognized Bachelor of Science Program in Computer Science. A Master’s degree in a relevant field would be a strong asset. 
  • Two (2) years of recent related experience or an equivalent combination of education, training, and experience acceptable to the project lead.

Core Skills and Abilities 

  • Expertise with Python 3.X and able to provide links to code samples via GitHub or another open repository
  • Comfortable working in a Unix environment, including experience with shell scripting and common command-line tools
  • Familiarity with molecular and cellular biology
  • Excellent verbal and written communication skills.
  • Demonstrated ability to efficiently organize work assignments and establish priorities.
  • Demonstrated interpersonal skills including the ability to work effectively with others in a team environment.

Additional Assets

  • Familiarity in statistical analysis using modern computational tools.  Experience with any relevant tools will be considered, but R and Python are preferred
  • Familiarity with the development, testing, and maintenance of relational databases
  • Familiarity in next-generation sequencing
  • Experience with software testing
  • Experience with Agile software practices
  • Functional knowledge of distributed version control systems, such as SVN or GIT

To Apply

Please submit a detailed cover letter and resume to bcgscjobs@bcgsc.ca, using Job Reference No.: RP_R00008_Karsan Lab_2021_04_19  in the subject line of your email.

This posting will remain online until filled.

Important!

Due to current COVID-19 restrictions, the position would require working remotely within British Columbia on a temporary basis with an ability to come to the normal workplace within reasonable notice. This restriction would be re-evaluated after finalization of reopening plans.

As per the current Public Health Order, full vaccination against COVID-19 is a condition of employment with PHSA as of October 26, 2021.

We believe that diversity and inclusivity are essential for the advancement of human knowledge and science.

We welcome all applicants and provide all employees with equal opportunity for advancement, regardless of race, colour, ancestry, place of origin, political belief, religion, marital status, family status, physical or mental disability, sex, sexual orientation, gender identity or expression, age, conviction of a criminal or summary conviction offence unrelated to their employment.

All qualified candidates are encouraged to apply; however, Canadian citizens and permanent residents will be given priority.

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