Acute Myeloid Leukaemia (AML) is a disease normally found in elderly patients, with the median age of presentation at about 68 years. At this age, many of the patients are frail and unlikely to respond well to intensive chemotherapy treatments. Conventional chemotherapy eradicates the proliferating leukaemic progenitors while leaving the quiescent leukaemic stem cells undisturbed. These quiescent LSCs are able to then bring about leukaemic relapse. Fumagillin is a natural metabolite from Asperigillus fumigatus that is generally used as an anti-microbial agent but it is also known to bind to intracellular MetAP-II and inhibit endothelial cell growth. Many cancers are found to have an over expression of MetAP-II. In the past, MetAP-II inhibitors have been tested and shown success in angiogenesis inhibition and tumor reduction. The aim of this study is to observe whether methionine aminopeptidase-2 inhibitors can be used in the treatment of acute myeloid leukemia. The investigation included a dose response comparison of various AML cell lines to fumagillin treatment, cell proliferation assay, a colony forming unit assay, and cell cycle analysis of KG-1 cells following three days of fumagillin treatment. I have determined that fumagillin does indeed decrease the cellular proliferation of KG-1 in vivo and at 10μM, prevents colony formation in methylcellulose plating. There is an increase in cells found in the sub-G1 phase with fumagillin treatment, as analyzed by flow cytometry. It is interpolated that fumagillin treatment increases AML cell apoptosis, in addition to hindering its ability to grow in culture. / published_or_final_version / Medicine / Master / Master of Medical Sciences

Acute Myeloid Leukemia (AML), the most common form of acute leukemia in adults, is only curable in approximately 30% of all cases. Despite prognostic risk stratification using sub-typing and cytogenetic analysis to direct therapy, the mortality and relapse rate remains high. AML patients with normal karyotypes are defined as intermediate risk and are the most challenging to treat. Somatic mutations may be the key in refining prognostic stratification and providing useful therapeutic targets. The FMS-like tyrosine kinase 3 (FLT3) and Nucleophosmin (NPM1) genes have common mutated forms that are associated with overall survival and response to therapy. We assessed mutations in the FLT3 and NPM1 genes and their levels of expression in twenty eight AML patients in the presence and absence of HIV and their response to induction therapy. Furthermore, we used a novel technique, High Resolution Melting (HRM) Analysis to detect FLT3 Internal Tandem Duplications (ITD) and NPM1 exon 12 mutations. Five of the patients in this study were HIV positive, three of whom did not survive post-induction therapy. Of the AML patients, 17.9% were positive for the NPM1 mutation and 21% had mutated FLT3. Interestingly, the presence of the FLT3 and NPM1 mutations were coupled with an increase in expression levels of FLT3 and NPM1 from presentation to post-induction respectively and the loss of these mutations were coupled with a decrease in levels of expression from presentation to post-induction. However, an increase/decrease from presentation to post-induction did not necessarily denote the presence/absence of a mutation. Therefore, while mutational status of genes may generally confer mRNA levels, our results showed that there existed no definitive trend between mRNA levels of NPM1 and FLT3 expression and mutational status. We found that the HRM method was definitive for the simpler NPM1 mutation however detection of the FLT3-ITD mutation was challenging. There isn’t a clear distinction between mutated and non-mutated FLT3 due to the formation of hetero-duplexes during analysis, making detection highly subjective and error-prone. Sequencing allowed confirmation of mutated FLT3 and non-mutated FLT3 which were not in all instances in concordance with HRM analysis. The prognostic value in terms of overall survival of NPM1 and FLT3 mutations in this study is indefinite. Furthermore, the analysis of the HIV positive AML patients revealed no clear correlation between NPM1 and FLT3 levels of mRNA expression and mutational status. Also, the small number of HIV positive AML patients did not allow for conclusions to be made regarding HIV status and survival when affected with AML. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.