Virtual Library

Start Your Search

Paola A Marignani



Author of

  • +

    MA24 - Genomic Evolution, KEAP 3 and More Non-Coding RNA (ID 928)

    • Event: WCLC 2018
    • Type: Mini Oral Abstract Session
    • Track: Biology
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/26/2018, 10:30 - 12:00, Room 205 BD
    • +

      MA24.11 - Loss of Tumour Suppressors is Adequate and Sufficient to Drive Lung Cancer in CRISPR/Cas9 Mice. (ID 14026)

      11:40 - 11:45  |  Presenting Author(s): Paola A Marignani

      • Abstract
      • Presentation
      • Slides

      Background

      In non-small cell lung carcinoma (NSCLC), loss-of-function (LOF) mutations are found in tumour suppressors, highlighting the importance of these genes in the aetiology of lung cancer. The major tumour suppressors (TS) associated with the development of lung cancer are p53, and the kinase LKB1. Unlike oncogenes that have been successfully exploited therapeutically, LOF alterations in TS are difficult to exploit. The goal of our research is to understand how the loss of TS function allows for metabolic and epigenetic adaptation that favour conditions for tumour growth.

      a9ded1e5ce5d75814730bb4caaf49419 Method

      We developed a CRISPR/Cas9 mouse model of lung cancer representative of tumour suppressors lost in NSCLC. Since LKB1 and p53 are two of the most common LOF tumour suppressors found in NSCLC along with activating mutations in Kras, we used a Cre-dependent Cas9 mouse to create mice that simultaneously lack pulmonary Lkb1 and p53 along with activating KRasG12D. Here, we evaluated the development of lung cancers in the context of metabolism and epigenetic marks.

      4c3880bb027f159e801041b1021e88e8 Result

      The metabolic profile of lung tumours harvested from CRISPR/Cas9 mice was significantly different from the mTOR and metabolic profile of lungs harvested from control mice, favouring a switch from glycolysis to mitochondrial metabolism. Epigenetic marks; acetylation and methylation modifications to histones 3 (H3) and H4 were significantly different compared to control mice, indicative of poor prognosis.

      8eea62084ca7e541d918e823422bd82e Conclusion

      Our study is the first to characterize a new CRISPR/Cas9 mouse model for lung cancer that leverages the loss of two common tumour suppressor proteins associated with lung cancer; Lkb1, and p53. We show that the simultaneous loss of these TS leads to activation of mTOR and pro-survival pathways sustained by metabolic adaptation. Further to this, we observe epigenetic marks that agree with poor prognosis. We conclude from our study that patients with lung cancers that lack expression of LKB1 are likely to respond favourably to interventions that simultaneously target aberrant metabolism with modifiers of tumour epigenetic landscape. Our findings suggest that loss of LKB1 expression serves as a marker for NSCLC.

      6f8b794f3246b0c1e1780bb4d4d5dc53

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Information from this presentation has been removed upon request of the author.

  • +

    P3.03 - Biology (Not CME Accredited Session) (ID 969)

    • Event: WCLC 2018
    • Type: Poster Viewing in the Exhibit Hall
    • Track:
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/26/2018, 12:00 - 13:30, Exhibit Hall
    • +

      P3.03-02 - Single-Cell RNA-Seq in Human Lung Cancer (ID 13405)

      12:00 - 13:30  |  Author(s): Paola A Marignani

      • Abstract

      Background

      Lung cancer has the highest mortality rate amongst cancers primarily due to delay of diagnosis. Until recently, the focus on genomic and transcriptomic characterization of lung cancers has guided to the diagnosis and treatments of the cancers. Although RNA sequencing (RNA-seq) has been used for transcriptome profiling in cancer research, few studies have employed single cell (sc) RNA-seq approaches to investigation of the heterogeneity among individual cells directly isolated from resected surgical human lung cancer tissues. The aim of our work is to identify new biomarkers indicating early stage versus late stage of lung cancers. As an initiative step, the current study presents a profile of differentially expressed genes (DEG) of single cells of lung cancer tissues collected from diverse lung cancer patients.

      a9ded1e5ce5d75814730bb4caaf49419 Method

      Tumours resected from lung cancer patients were prepared for scRNA-seq. Microfluidic system, C1 (Fluidigm), was used to capture individual cells, and full-length cDNAs (FL-cDNA) were synthesized in the system. Next-generation sequencing (Illumina) of FL-cDNA libraries generated sequence reads from transcriptomes of single and bulk cells, respectively. Following read mapping, DEGs were selected by >2x fold-change difference in normalized expression values. qPCR was employed to validate transcriptional changes in selected DEGs comparing expression values resulted from scRNA-seq and bulk RNA-seq. Both gene set enrichment and signaling pathway analyses were used to identify mechanism of action for validated DEG-encoding molecules.

      4c3880bb027f159e801041b1021e88e8 Result

      Raw scRNA-seq datasets were processed for read mapping. More than 1 million processed reads per single-cell FL-cDNA library were used for DEG selection. We examined standard deviation of normalized expression value per selected DEG to characterize transcriptomic features of individual tumour cells. We identified a minimum of a dozen DEGs showing certain fold-change differences in each stage of lung cancers. Selected DEGs were validated by qPCR whereby unique patterns of gene expression at specific stages were confirmed.

      8eea62084ca7e541d918e823422bd82e Conclusion

      The heterogeneity of lung cancers coupled with late stage diagnosis contributes to poor outcomes. The advent of scRNA-seq allows for the identification of differential gene expression and stage-specific markers that can be used to improve our understanding of highly complex intratumour heterogeneity in lung cancers. In the future, our discoveries will lead to the development of targeted therapies based on validated DEGs, ultimately allowing for early diagnosis, treatment and improved lung cancer survivorship.

      PAM is supported by CCSRI-i2I and DMRF.

      6f8b794f3246b0c1e1780bb4d4d5dc53

      Information from this presentation has been removed upon request of the author.

  • +

    P3.13 - Targeted Therapy (Not CME Accredited Session) (ID 979)

    • Event: WCLC 2018
    • Type: Poster Viewing in the Exhibit Hall
    • Track:
    • Presentations: 1
    • Moderators:
    • Coordinates: 9/26/2018, 12:00 - 13:30, Exhibit Hall
    • +

      P3.13-31 - Creating a Precision Medicine Pipeline for Lung Cancers. (ID 14006)

      12:00 - 13:30  |  Presenting Author(s): Paola A Marignani

      • Abstract

      Background

      The vision of High Mortality Cancer Precision Medicine Pipeline (HMCPMP) is to improve high mortality cancer outcomes. Our mission of HMCPMP is to establish precision medicine pipelines for high mortality cancers that start with the patient and ends with precise treatments for the patient based on their lung cancer’s unique molecular profile. HMCPMP leverages expertise areas of i) single-cell gene-discovery that allows for the identification of new barcodes and therefore new targets, ii) animal models that recapitulate human cancers, and patient-derived xenographs that allow for pre-clinical trials in mouse models to test novel drugs and drug development, iii) immunology and cancer stem cell biology to explore the role the immune system and stem cell niche impact tumourigenesis, iv) single-cell fluidics/3D organ systems that allow for understanding the heterogeneity of cancers and vi) data mining that allows for better treatment choices and the discovery of new treatment options based on their lung cancer’s barcodes.

      a9ded1e5ce5d75814730bb4caaf49419 Method

      We have created a patient-centered precision medicine pipeline that moves resected lung cancers from the surgical suite to banking, through to single cell molecular diagnostics to validation (Figure 1). pipeline_lung_cancers.jpg

      4c3880bb027f159e801041b1021e88e8 Result

      Single-cell genomic profiling of resected lung cancers were prepared using a microfluidics platform Fluidigm C1 followed by transcriptome sequencing per single cell. We identified differentially expressed genes (DEGs) for stage, sex, and smoking status, followed by validation by quantitative PCR. We are currently pursuing new barcodes that differentially distinguish between the stratified subgroups of patients.

      8eea62084ca7e541d918e823422bd82e Conclusion

      The significance of HMCPMP research is improved health, survivorship, and quality of life for people living with lung cancer. Although the economics of lung cancer are important and likely drivers of federal, provincial and regional research initiative, HMCPMP considers the human when faced with the diagnosis of lung cancer.

      PAM is funded by the Dalhousie Medical Research Foundation and the Canadian Cancer Society

      6f8b794f3246b0c1e1780bb4d4d5dc53

      Information from this presentation has been removed upon request of the author.