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Cancer metabolism and its role in the sensitivity to ASNase of leukemic cells to L-asparaginase
Alquezar Artieda, Natividad ; Starková, Júlia (advisor) ; Procházka, Vít (referee) ; Truksa, Jaroslav (referee)
Cancer metabolism and its role in the sensitivity of leukemic cells to L- asparaginase ABSTRACT No ultimate treatment strategy exists for relapsed or non-responsive (15-20%) children with acute lymphoblastic leukemia (ALL). In this study, we aimed to elucidate the impact of metabolic rewiring in leukemic cells on poor therapy response and the emergence of resistance. This dissertation focuses on l-asparaginase (ASNase), a crucial chemotherapeutic agent and its effect on leukemia, using models of leukemic cell lines and primary cells of ALL patients. Cell metabolism was assessed by measuring metabolic pathways and nutrient influx using a Seahorse analyzer and stable isotope tracing. Main findings of the study demonstrated that the ASNase- therapy response was mitigated by the activity of the mechanistic target of rapamycin (mTOR)- regulated biosynthetic pathways. This phenomenon was induced by the bone marrow environment, which enabled the activation of the resistant mechanism in leukemic cells. We next found a correlation between the following metabolic features and lower sensitivity to ASNase: low ATP- linked respiration, high mitochondrial membrane potential and high glycolytic flux before therapy. The latter was shown to have prognostic implications. Moreover, high glycolytic flux was detected in T-ALL...
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Characterization of a role of selected antiapoptotic Bcl-2 family proteins in mitochondrial metabolism.
Antoš, Šimon ; Anděra, Ladislav (advisor) ; Brábek, Jan (referee)
Proteins from the Bcl-2 family are now for over 30 years widely studied mainly for their key role in apoptosis, a principal mode of regulated cell death. In the last ten years Bcl-2 proteins were also linked to the regulation of cellular signaling, mainly cellular metabolism and respiration. In this study we aimed to analyze non-apoptotic function of Bcl-2 proteins by their genetic elimination using the CRISPR-Cas12a approach and by the subsequent analysis of mitochondrial respiration, glycolysis and metabolic profiling. Our results confirmed that Bcl-2 proteins can modulate the level of mitochondrial respiration. The elimination of anti-apoptotic proteins Bcl-2, Bcl-XL and Mcl-1 decreased high respiration of cells lacking pro-apoptotic proteins Bax and Bak to the levels observed in parental U87-MG glioblastoma cells. Therefore, the loss of anti-apoptotic Bcl-2 proteins has greatly impacted mitochondrial respiration and it points to their role in a regulation of oxidative phosphorylation.
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Role of sulfhydryl oxidase 1 in cancerogenesis
Beranová, Lea Marie ; Truksa, Jaroslav (advisor) ; Šuťák, Róbert (referee)
Disulfide bridges play a significant role in protein-folding as well as en- zyme activity and thus regulate many intra- and extracellular processes. Sulfhydryl oxidase QSOX1 forms S-S bridges de novo, modulating the activity of its substrates and thus directly or indirectly influences vital cel- lular processes. The first part of this thesis focuses on characterization of the role of QSOX1 in cancerogenesis, using breast cancer cell lines (MCF7, MDA-MB-231) and pancreatic cancer cell line (Panc-1), while the second part emphasizes the regulation of QSOX1 expression by different oxygen concentrations. To study the effect of QSOX1 on proliferation of triple-negative cancer cells MDA-MB-231, two genetically modified cell lines - QSOX1-overexpressing and QSOX1 knockout cell lines - were constructed. While increased QSOX1 protein levels do not have a significant effect, the absence of QSOX1 leads to a decreased cellular growth. Lack of QSOX1 also results in visible change in cellular morphology. QSOX1 knockout cells can be mostly characterized as more round-shaped with less noticeable or completely missing lamellipo- dia. This finding is with agreement with to-date literature suggesting that QSOX1 is important not only for cellular proliferation but also for migration and invasiveness. While authenticating the theory of...
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Role of sulfhydryl oxidase 1 in cancerogenesis
Beranová, Lea Marie ; Truksa, Jaroslav (advisor) ; Šuťák, Róbert (referee)
Disulfide bridges play a significant role in protein-folding as well as en- zyme activity and thus regulate many intra- and extracellular processes. Sulfhydryl oxidase QSOX1 forms S-S bridges de novo, modulating the activity of its substrates and thus directly or indirectly influences vital cel- lular processes. The first part of this thesis focuses on characterization of the role of QSOX1 in cancerogenesis, using breast cancer cell lines (MCF7, MDA-MB-231) and pancreatic cancer cell line (Panc-1), while the second part emphasizes the regulation of QSOX1 expression by different oxygen concentrations. To study the effect of QSOX1 on proliferation of triple-negative cancer cells MDA-MB-231, two genetically modified cell lines - QSOX1-overexpressing and QSOX1 knockout cell lines - were constructed. While increased QSOX1 protein levels do not have a significant effect, the absence of QSOX1 leads to a decreased cellular growth. Lack of QSOX1 also results in visible change in cellular morphology. QSOX1 knockout cells can be mostly characterized as more round-shaped with less noticeable or completely missing lamellipo- dia. This finding is with agreement with to-date literature suggesting that QSOX1 is important not only for cellular proliferation but also for migration and invasiveness. While authenticating the theory of...
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Impairment of cellular metabolism as common pathophzsiological mechanism of CNS diseases
Hasala, Ondřej ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Name of thesis: Impairment of cellular metabolism as common pathophysiological mechanism of CNS diseases Problem definition: Every human cell needs energy for living. If the prodcution of ATP (as an universal energy carrier) is broken, cell restricts its activity first and during longterm depletion of ATP, dies. It was found, that cellular metabolism is broken in most pathologies in CNS. Disorder of respiratory chain by free radicals is the best known at Parkinson's disease, epilepsy, brain ischemia etc. Mitochondria, where respiratory chain is situated, is not only the aim of free radicals, but it is their major producer. The activity of respiratory chain decreases during the life and this phenomenan is called aging. Aim of thesis: To determine whether there is increased production of free radicals in mitochondria of rat (LE Wistar) hippocampus during the epileptic seizure. Method: Thesis involves experiment which was done with acute rat hippocampal slices. To induce epileptic seizure it was used 4-aminopyridine model. It was used fluorescence imaging as imaging method. Changes of superoxide production was detected with MitoSOX. Electrophysiological record was taken by programme Spike 2 with stimulation and recording electrode inside the slice. Results: There was no significant difference between...
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