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Mitochondrial dysfunction in brain tumors
Rollerová, Kateřina ; Vaňátko, Ondřej (advisor) ; Zobalová, Renata (referee)
Brain tumors are one of the most serious pathologies of the central nervous system. Brain tumors are aggressive and very hard to treat due to the fragile nature of the nervous system, presence of blood-brain barrier and high recurrence rate. One of the hallmarks of brain tumors is mitochondrial dysfunction. Mitochondria are organelles involved in essential cellular processes, such as energy production, redox and calcium signaling, or the regulation of cell death. Structural and functional abnormalities, mutations in the mitochondrial genome and other mitochondrial dysregulations may cause disruptions in various cellular processes, such as production of reactive oxygen species, migration, proliferation, or regulation of cell death, promoting the development and/or maintenance of brain tumors. The goal of this thesis is to summarize current knowledge about mitochondrial dysfunction in brain tumors. Key words: brain tumors; mitochondria; mitochondrial dysfunction; Warburg effect; apoptosis; reactive oxygen species; isocitrate dehydrogenase
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Multiple forms of dipeptidyl peptidase IV and fibroblast activation protein in brain tumors
Matrasová, Ivana ; Šedo, Aleksi (advisor) ; Kupcová Skalníková, Helena (referee) ; Modrianský, Martin (referee)
Proteolytic enzymes are known to contribute to the initiation, development and progression of a number of diseases. Dipeptidyl peptidase IV (DPP-IV) and fibroblast activation protein (FAP) are serine proteases with the unique ability to cleave dipeptides containing - highly evolutionarily conserved - proline at the penultimate position of the N- terminus of substrates/biologically active peptides. FAP also exhibits gelatinolytic activity, which it exerts during extracellular matrix remodeling processes. Glial brain tumors (gliomas) arise from resident transformed glial cells, whereas brain metastases originate from circulating transformed extracranial tumor cells. Our previous work has described an increased expression of DPP-IV and FAP in high-grade glioma tissues. The presence of DPP- IV and FAP in brain metastatic tissues has not been described to date. The aim of this thesis was to describe the multiple forms of DPP-IV and FAP, and to describe their cellular origin and possible regulation in brain tumors. DPP-IV and its molecular MW and pI forms were expressed predominantly by transformed glial cells, whereas FAP and its MW and pI forms were expressed by transformed and stromal cells present in GBM and brain metastatic tissues. The spectrum of multiple forms of DPP-IV and FAP in GBM tissues and...
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Current trends in radiotherapy of brain tumors
BĚHAN, Daniel
The bachelor thesis deals with modern radiotherapeutic treatment of brain tumors. The theoretical part is devoted to the classification of these types of tumors, the effects of radiation on the cell, the side effects of radiotherapy, fractionation schemes, treatment planning and the combination of radiotherapy with chemotherapy. The main goal of the bachelor's thesis was to compare the number of patients at three selected workplaces, namely gammaknife, tomotherapy and linear accelerator. Out of the total number of 3500 patients irradiated on gammaknife during the years 2019-2021, 3024 patients underwent treatment of primary and secondary tumors, the rest of the irradiated patients represent non-tumor irradiation of vascular, functional and ocular disorders, thus 14% of the total number of treated patients. The analysis of the collected data showed an increase in the number of treated patients in 2020. The cause of this could theoretically be installation of a new type of Gamma Knife Icon, which took place in November 2019. After calculating the correlation analysis, it was found that the numbers of patients do not correlate with the installation of a new device. Data obtained from patients irradiated on tomotherapy pointed to the fact that the tomotherapeutic device is used in the treatment of brain tumors only in a small percentage (4 % of treated patients) and it is used more for the treatment of other malignancies. The number of patients with brain cancer irradiated on a linear accelerator was about 7 % of all patients. The most common cause of brain lesions was distant metastases of non-small cell and small cell lung cancer, which is confirmed by information obtained from the literature, which states that lung cancer is the most common metastatic tumor to the brain. Glioblastoma multiforme was the most common group of primary tumors. The last goal for the elaboration of the bachelor's thesis was a more detailed description of the construction of the irradiation pavilion and the installation of the newly purchased and currently the most modern radiotherapy device CyberKnife at the ÚVN in Prague.
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Role of Exosomes in the Progression, Diagnosis, and Treatment of Brain Tumors
Vaníková, Lucie ; Zíková, Martina (advisor) ; Lacina, Lukáš (referee)
Recent studies have confirmed the importance of extracellular vesicles, particularly exosomes, in the development of brain tumors. Considerable attention has been paid mainly to the influence of exosomes on biological processes in brain tumors. Exosomes mediate intercellular communication in the tumor microenvironment by transporting biomolecules. Most often they transmit various types of ribonucleic acids, specifically microRNAs, which affect the signalling pathways related to tumour growth in target cells. Thus, exosomes play an important role in tumor cell proliferation and differentiation, metastasis, and tumor resistance to chemotherapy or radiation. Due to their small size, exosomes can cross the blood-brain barrier and thus promote tumor progression. The topic of the bachelor thesis is a summary of the current knowledge on the role of exosomes in brain tumor progression, diagnosis and treatment.
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Statistics-based Diagnostics of Brain Tumors
Marcon, P. ; Bartušek, Karel ; Dohnal, P. ; Širůčková, K.
Currently, the increasing number of reported cancer cases has become a serious indicator of persisting low curability rates characterizing certain prominent diseases. An early tumor diagnosis constitutes a vital prerequisite for any potentially successful therapy, in this context, the present paper discusses the improvement of accuracy in the overall diagnostics related to brain tumors. The proposed measures include, for example, maximizing the use of image modifications and decreasing the radiation doses received by a patient's body. The wider project is centered on the diagnostics of pathological tissues in the brain, it describes and compares the classification and identification of particular brain tumors. For the given purpose, images were acquired via magnetic resonance tomography.
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