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3D models of brain tumors
Fišer, Ondřej ; Novák, Josef (advisor) ; Bohačiaková, Dáša (referee)
Despite intensive research, glioblastoma multiforme remains one of the tumours of the central nervous system with the worst prognosis. The ability of glioblastoma cells to infiltrate brain tissue by forming invasive microtubular structures is stimulated by contact with adjacent non- tumor cells. Intercellular communication and the influence of the extracellular matrix create a specific microenvironment that affects cell signaling, proliferation, differentiation and response to pharmaceuticals. The recurrent form of glioblastoma often displays a much faster progression than the initial disease, which is attributed to the development of resistance to therapeutics and the preservation of the proliferative capacity of some tumour cells. The discovery of the stem- cells ability to self-aggregate in suspension has led to the creation of 3D in vitro models - brain organoids. They are much more complex that the established 2D models and their heterogeneity provides an environment simulating the in vivo state. This thesis aims to describe their use in brain tumour research and techniques for culturing 3D aggregates of neural lineage formed from induced or embryonic human stem cells with respect to their gradually increasing complexity. It also presents methods of addressing issues of hypoxia, organoid...
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Studies of intercellular interactions in tumours
Jechová, Alžběta ; Smetana, Karel (advisor) ; Skalníková, Helena (referee) ; Masařík, Michal (referee)
Beside tumor cells themselves, tumors consist of many non-malignantly transformed cellular elements and an extracellular matrix. This so-called tumor microenvironment, or stroma, significantly influences the biological properties of the tumor through intercellular interactions. In this thesis I have focused on the study of tumor-associated fibroblasts in squamous cell carcinomas of the head and neck, malignant melanoma and glioblastoma. The data show the presence of cells with mesenchymal characteristics, present even in the glioblastoma stroma, which could potentially have a positive effect on proliferative activity and invasiveness of glioblastoma cells. In malignant melanoma, the presence of keratinocytes should also be considered, as they are the major cells of the epidermis influencing tumor melanocytes. The conditioned medium from UVB irradiated keratinocytes and non-irradiated fibroblasts stimulates the invasion of malignant melanoma cells. Targeting the tumor stroma may be a new direction in oncological therapy, so we have focused on the influence of synthetic polyamine on the formation of myofibroblasts, which are an active part of the population of tumor-associated fibroblasts. The tested polyamine prevents the formation of myofibroblasts but has no effect on those already formed nor on...
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Uloha kataninu, ATPázy štěpící mikrotubuly, při modulaci buněčné motility a proliferace glioblastomových buněk.
Uhlířová, Jana ; Dráber, Pavel (advisor) ; Libusová, Lenka (referee)
Glioblastomas are the most common and the deadliest types of brain tumours. Due to their highly invasive behaviour, they are incurable by convencial therapeutical strategies. It was shown that some components of microtubules, namely class III β-tubulin, γ-tubulin and microtubule severing protein spastin are overexpressed in glioblastoma cell lines as well as glioblastomas. This diploma thesis is focused on the expression, subcellular distribution and function of katanin, another microtubule-severing enzyme, in gliobastoma cell lines. Katanin is formed by catalytic (p60) and regulatory (p80) subunits. Expression and cellular localization of both katanin subunits was studied in panel of human glioblastoma cell lines isolated form adults (T98G, U87MG, U118MG and U138 MG) and child (KNS42). Data presented in this thesis demonstrated that katanin subunits were overexpresed both on transcript and protein levels in T98G, U87MG and KNS42 cell lines, but not in U138MG and U118MG cell lines when compared to normal non- transformed human astrocytes. Immunofluorescence microscopy revealed that both katanin subunits were diffusively distributed in cytoplasm and concentrated on spindle poles of mitotic cells and on leading edges of migrating cells. Examination of cell motility revealed that velocities in...
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Magnetic resonance imaging of central nervous system lymphoma.
Koubská, Eva ; Malíková, Hana (advisor) ; Kalvach, Pavel (referee) ; Druga, Rastislav (referee)
Background: The aim of this study was to describe the morphological signs of the central nervous system lymphoma (CNSL) in magnetic resonance imaging (MRI). We compared morphological characteristics of primary CNSL (PCNSL) and secondary CNSL (SCNSL) and also of PCNSL and glioblastoma (GBM). Methods: We included 64 patients with PCNSL (ten of them were immunocompromised), 21 patients with SCNSL and 54 patients with GBM. The diagnosis was confirmed histologically in all patients. We evaluated morphological signs on the first MRI examination. Additionally, in patients with PCNSL, we evaluated the development of the disease on follow-up examination before histological confirmation of the diagnosis, if available. Results: In most patients with PCNSL (62.5%) the tumor was localized supratentorially and presented as multiple lesions (53.1%) or as a diffuse infiltrative lesion (23.4%). In 87.5% of the patients the lesions reached the brain surface. Infiltration of ependyma was seen in 56.3%, infiltration of meninges in 39.1% and infiltration of cranial nerves in 48.5% of patients. Restriction of diffusion in some part of the tumor was apparent in nearly all patients (97.6%) with PCNSL. After administration of contrast media, marked enhancement was usually seen. In immunocompetent patients, homogenous...
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The role of cellular senescence in carcinogenesis and aging of the brain
Paroubková, Michaela ; Hodný, Zdeněk (advisor) ; Horníková, Daniela (referee)
The risk of developing many pathological conditions and ageing-releated diseases increases persistently throughout a lifetime. A dramatic increase in the number of people suffering from one of these diseases, such as atherosclerosis, Alzheimer's disease or Parkinson's disease, is caused by constant elevation of human life's length due to advancements in modern medicine and changes in life style. Several recent studies have demonstrated that senescent cells accumulate in aged and ill tissues. Senescent cells are metabolically active, but unable of proliferation and unlike the terminally differented cells, they secrete many factors that contribute to the transformation of the tissue microenviroment. The role of senescence as anticancer barier is known for a long time, but its importance in physiological processes and aging is mainly a matter of a recent time. While there is also a lot of studies focusing on cellular senescence in peripheral tissues, their involvement in or contribution to cognitive decline with aging of the central nervous system (CNS) remains relatively unknown. Recent data of many laboratories suggest that senescence-associated secretory phenotype of the non-neuronal senescent cells in brain can cause chronic level of inflammation and thus accompany aging and ageing-related...
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Complex Preoperative Brain Tumor Imaging
Tupý, Radek ; Ferda, Jiří (advisor) ; Vymazal, Josef (referee) ; Tüdös, Zbyněk (referee)
Title Complex preoperative brain tumor imaging Abstract The differentiation of glioblastoma, metastases and brain lymphoma using modern diagnostic imaging methods has a major impact on the strategy of further diagnostic examinations and treatment. In a group of 67 patients with glioblastoma and 31 with cerebral metastasis, the ability to differentiate them according to the evaluation of perfusion parameters changes in peritumoral white matter by T1 dynamic post-contrast magnetic resonance imaging was verified, with the positive predictive value in glioblastoma detection up to 91%. In a group of 36 brain lymphoma patients the importance of imaging submodalities and contribution of a complex magnetic resonance imaging protocol to detect lymphoma up to 80% were evaluated. Key words brain, glioblastoma, lymphoma, magnetic resonance imaging, neoplasm metastasis
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Definition of the expression pattern of DASH system in transformed glial cells, the coupled expression of fibroblast activation protein and dipeptidyl peptidase-IV.
Balážiová, Eva ; Šedo, Aleksi (advisor) ; Borovanský, Jan (referee) ; Mareš, Vladislav (referee)
Dipeptidyl peptidase-IV (DPP-IV) is a multifunctional transmembrane glycoprotein removing X-Pro dipeptide from the amino-terminus of the peptide chain. This evolutionary conserved sequence protects a number of biologically active peptides against the unspecific proteolytic cleavage. DPP-IV belongs into the group of "Dipeptidyl peptidase-IV Activity and/or Structure Homologues" (DASH), which, except the canonical DPP-IV, comprises fibroblast activation protein-α/seprase (FAP), and several other molecules. However several of DASH molecules are the enzymes, they execute at least some of their biological functions by non-proteolytic protein-protein interactions. DASH molecules, their substrates and binding partners are parts of "DASH system" which is affected in several pathological process including a cancer. Specifically DPP-IV and its closest structural relative FAP are among others expected to be involved in the development and progression of malignant glioma. In this study we showed the expression and colocalization of DPP-IV and FAP in glioma cells in vitro and in human high grade gliomas. In addition to the DPP-IV/FAP double positive transformed glial cells, we also identified a subpopulation of FAP positive mesenchymal cells located in the perivascular compartment. Moreover we described the...
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Magnetic resonance imaging of central nervous system lymphoma.
Koubská, Eva ; Malíková, Hana (advisor) ; Kalvach, Pavel (referee) ; Druga, Rastislav (referee)
Background: The aim of this study was to describe the morphological signs of the central nervous system lymphoma (CNSL) in magnetic resonance imaging (MRI). We compared morphological characteristics of primary CNSL (PCNSL) and secondary CNSL (SCNSL) and also of PCNSL and glioblastoma (GBM). Methods: We included 64 patients with PCNSL (ten of them were immunocompromised), 21 patients with SCNSL and 54 patients with GBM. The diagnosis was confirmed histologically in all patients. We evaluated morphological signs on the first MRI examination. Additionally, in patients with PCNSL, we evaluated the development of the disease on follow-up examination before histological confirmation of the diagnosis, if available. Results: In most patients with PCNSL (62.5%) the tumor was localized supratentorially and presented as multiple lesions (53.1%) or as a diffuse infiltrative lesion (23.4%). In 87.5% of the patients the lesions reached the brain surface. Infiltration of ependyma was seen in 56.3%, infiltration of meninges in 39.1% and infiltration of cranial nerves in 48.5% of patients. Restriction of diffusion in some part of the tumor was apparent in nearly all patients (97.6%) with PCNSL. After administration of contrast media, marked enhancement was usually seen. In immunocompetent patients, homogenous...
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The role of cellular senescence in carcinogenesis and aging of the brain
Paroubková, Michaela ; Hodný, Zdeněk (advisor) ; Horníková, Daniela (referee)
The risk of developing many pathological conditions and ageing-releated diseases increases persistently throughout a lifetime. A dramatic increase in the number of people suffering from one of these diseases, such as atherosclerosis, Alzheimer's disease or Parkinson's disease, is caused by constant elevation of human life's length due to advancements in modern medicine and changes in life style. Several recent studies have demonstrated that senescent cells accumulate in aged and ill tissues. Senescent cells are metabolically active, but unable of proliferation and unlike the terminally differented cells, they secrete many factors that contribute to the transformation of the tissue microenviroment. The role of senescence as anticancer barier is known for a long time, but its importance in physiological processes and aging is mainly a matter of a recent time. While there is also a lot of studies focusing on cellular senescence in peripheral tissues, their involvement in or contribution to cognitive decline with aging of the central nervous system (CNS) remains relatively unknown. Recent data of many laboratories suggest that senescence-associated secretory phenotype of the non-neuronal senescent cells in brain can cause chronic level of inflammation and thus accompany aging and ageing-related...
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Studies of intercellular interactions in tumours
Jechová, Alžběta ; Smetana, Karel (advisor) ; Skalníková, Helena (referee) ; Masařík, Michal (referee)
Beside tumor cells themselves, tumors consist of many non-malignantly transformed cellular elements and an extracellular matrix. This so-called tumor microenvironment, or stroma, significantly influences the biological properties of the tumor through intercellular interactions. In this thesis I have focused on the study of tumor-associated fibroblasts in squamous cell carcinomas of the head and neck, malignant melanoma and glioblastoma. The data show the presence of cells with mesenchymal characteristics, present even in the glioblastoma stroma, which could potentially have a positive effect on proliferative activity and invasiveness of glioblastoma cells. In malignant melanoma, the presence of keratinocytes should also be considered, as they are the major cells of the epidermis influencing tumor melanocytes. The conditioned medium from UVB irradiated keratinocytes and non-irradiated fibroblasts stimulates the invasion of malignant melanoma cells. Targeting the tumor stroma may be a new direction in oncological therapy, so we have focused on the influence of synthetic polyamine on the formation of myofibroblasts, which are an active part of the population of tumor-associated fibroblasts. The tested polyamine prevents the formation of myofibroblasts but has no effect on those already formed nor on...
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