Dokument: Investigating the role of MALAT1, a long non-coding RNA, in glioblastoma tumorigenesis
| Titel: | Investigating the role of MALAT1, a long non-coding RNA, in glioblastoma tumorigenesis | |||||||
| URL für Lesezeichen: | https://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=61198 | |||||||
| URN (NBN): | urn:nbn:de:hbz:061-20221115-111706-6 | |||||||
| Kollektion: | Dissertationen | |||||||
| Sprache: | Englisch | |||||||
| Dokumententyp: | Wissenschaftliche Abschlussarbeiten » Dissertation | |||||||
| Medientyp: | Text | |||||||
| Autor: | Langini, Maike [Autor] | |||||||
| Dateien: |
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| Beitragende: | Prof. Dr. Stühler, Kai [Gutachter] Prof. Dr. Schmitt, Lutz [Gutachter] | |||||||
| Dewey Dezimal-Klassifikation: | 500 Naturwissenschaften und Mathematik » 570 Biowissenschaften; Biologie | |||||||
| Beschreibung: | This study aimed to increase the understanding of MALAT1s’ influence on protein signatures in GBM a highly malignant brain tumour with 5-year survival rates of approx. 5 % as well as a 90 % recurrence rate through a combination of interactomics, phenotype, proteomics and drug screening analyses.
LncRNAs such as MALAT1 previously thought to have no function could be employed as druggable targets as well as biomarkers. Therefore, investigation of their influence on protein signatures are necessary to increase the understanding of affected biological pathways and signalling cascades. • Through RNA-centric affinity enrichment, previously unknown putative MALAT1 interacting proteins were identified in established MB and GBM cell lines. In a GBM specific sample set involvement of MALAT1 in EGFR/PI3K signalling and cell cycle progression from G1- to S-phase was observed. • The phenotype study performed under application of the isogenic cell line pairs generated highlights the influence of MALAT1 in migration and proliferation events in a cell line-specific manner based on varying underlying biology. • Protein expression level analysis via nanoLC-MS approach shows that MALAT1 levels can indirectly affect protein expression levels. The link to EGFR/PI3K signalling observed in the interactome study is corroborated in this analysis and a cell line specific influence of MALAT1 based on the mutational background of the parental cell line was indicated. • The high-throughput drug screen employing one of the generated isogenic cell line pairs resulted in the identification of ZSTK474 as a drug candidate affecting MALAT1 linked signalling pathways in respective GBM cases. Orthogonal validation methods employed exhibited a treatment effect for ZSTK474 a pan PI3K inhibitor based on the MALAT1 expression level in the isogenic cell lines generated. • Through the combined data collected in this study several proteins, biological pathways, and phenotypical markers were shown to be affected by MALAT1 expression changes. The proteins H3F3A, TRIM28, PCNA, EFEMP1, and ZNF10 were linked to MALAT1 resulting in a potential linkage of this lncRNA to cell cycle progression, EGFR/PI3K, and DNA repair signalling pathways. This study shows that MALAT1 as a lncRNA can affect protein signatures in the investigated cell lines and that decreased MALAT1 expression levels can lead to phenotypic changes as well as perturbations in protein signalling cascades. While MALAT1 has already been shown to affect EGFR/PI3K signalling in tumours, the proposed modus operandi via transcriptional regulation of EFEMP1 and competitive binding to PCNA has not been described before in GBM. On basis of the data collected during this study, the observed effect of MALAT1 on cell cycle progression is proposed to be linked to competitive binding of PCNA and TRIM28 in GBM. SETD2 is a well-known MALAT1 interacting protein, however so far, no study has proposed the linkage between MALAT1, PCNA, H3F3A, and SETD2 to affect DNA repair signalling pathways via competitive binding events in GBM. Putative MALAT1 interactors identified in this study could be corroborated via reverse pulldowns with an RT-qPCR readout. The data obtained increased the knowledge of MALAT1s’ influence in GBM biology and revealed potential linkages to signalling pathways implicated in GBM tumorigenesis. | |||||||
| Lizenz: |  Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung 4.0 International Lizenz | |||||||
| Fachbereich / Einrichtung: | Mathematisch- Naturwissenschaftliche Fakultät » WE Chemie | |||||||
| Dokument erstellt am: | 15.11.2022 | |||||||
| Dateien geändert am: | 15.11.2022 | |||||||
| Promotionsantrag am: | 07.09.2022 | |||||||
| Datum der Promotion: | 02.11.2022 |
