dc.contributor.advisor |
El Hajj, Hiba |
dc.contributor.advisor |
Bazarbachi, Ali |
dc.contributor.author |
Machaalani, Charbel |
dc.date.accessioned |
2022-05-18T05:51:19Z |
dc.date.available |
2022-05-18T05:51:19Z |
dc.date.issued |
5/18/2022 |
dc.date.submitted |
5/10/2022 |
dc.identifier.uri |
http://hdl.handle.net/10938/23415 |
dc.description.abstract |
Acute myeloid leukemia (AML) is a genetically complex and highly
heterogeneous hematological malignancy. Despite the increasingly garnered molecular
knowledge, AML still associates with poor prognosis, high relapse rates, and resistance
to standard chemotherapy. Unraveling the molecular pathways of single or co-occurring
mutations is indispensable to improve AML management. under a broader research by
our team investigating relevant mutations in AML, we focused on select mutated genes.
Mutations in isocitrate dehydrogenase 1 or 2 (IDH 1/2) encoding for two known
epigenetic regulators and key enzymes of the Krebs cycle, occur in AML. These
mutations result in an aberrant enzymatic function, DNA hypermethylation, cell
proliferation and abnormal differentiation. Nucleophosmin-1 is a phosphoprotein playing
a pivotal role in several cellular processes and its gene mutations (NPM-1c) classify
among the most frequent mutations in AML patients. NPM-1c contributes but is not
sufficient to induce AML. Its occurrence with other mutations is key in AML
pathophysiology. Finally, P53, a well-known tumor suppressor, is mutated in 5 to 10%
of AML patients. We utilized Drosophila melanogaster model to study the phenotypic
effect of single mutations IDH1 R132H, IDH2 R172K, NPM1c, and P53 R248Q and
IDH1 R132H/ NPM1c double mutation. Transgenic flies were generated by injecting
pUAST vectors carrying the targeted wild-type human genes or their relevant mutations
in AML. Hemolectin-Gal4 system was used to express different proteins in the
hematopoietic fly compartments, and their phenotypic analysis was performed by
hemocyte enumeration. UAS-Gal4 system was used to specifically drive expression to
the eyes of adult flies. Phenotypic analysis was evaluated by Scanning Electron
Microscopy. We demonstrated that expression of IDH2 R172K or IDH1 R132H
mutations increase the number of circulating hemocytes and that IDH1 R132H induces
moderate roughness in the eyes of adult transgenic flies. NPM1c mutation increases
hemocyte count but does not induce any eye roughness in adults. Interestingly, IDH1
R132H/ NPM1c double mutation significantly increased circulating hemocytes counts as
compared to single mutations. Finally, and surprisingly, P53 R248Q mutation decreases
hemocyte count. Our study further validates the use of Drosophila to study mutations of
AML and sets a solid ground to map the molecular pathways by which these mutations
exert their biological phenotypes and to discover therapeutic susceptibilities providing
insights towards personalized medicine approaches. |
dc.language.iso |
en_US |
dc.subject |
AML |
dc.subject |
Leukemia |
dc.subject |
P53 |
dc.subject |
IDH1 |
dc.subject |
IDH2 |
dc.subject |
NPM1c |
dc.subject |
Drosophila melanogaster |
dc.subject |
Acute Myeloid Leukemia |
dc.title |
PHENOTYPIC CHARACTERIZATION OF HUMAN NPM-1C, IDH1, IDH2, AND P53 MUTATIONS AND THEIR COOPERATION IN ACUTE MYELOID LEUKEMIA USING DROSOPHILA MELANOGASTER MODEL |
dc.type |
Thesis |
dc.contributor.department |
Department of Experimental Pathology, Immunology, and Microbiology |
dc.contributor.faculty |
Faculty of Medicine |
dc.contributor.institution |
American University of Beirut |
dc.contributor.commembers |
Shirinian, Margret |
dc.contributor.commembers |
Abou Dalle, Iman |
dc.contributor.degree |
MS |
dc.contributor.AUBidnumber |
201700751 |