|
|
Molecular events associated with resistance to tyrosine kinase inhibitors in leukemia cells.
Hrdinová, Tereza
Chronic myeloid leukemia (CML) is a myeloproliferative stem cell disease characterized by the expression of BCR-ABL oncoprotein with constitutive tyrosine kinase activity. Although the development of tyrosine kinase inhibitors (TKI) such as imatinib dramatically improved the treatment of CML, a certain subset of patients develops resistance to TKI drugs. The most common cause of TKI resistance are point mutations in the BCR-ABL1 gene, followed by other mutation-independent mechanisms. Survival and proliferation of CML cells in the presence of TKI drugs are accompanied by adaptive changes in their metabolism. Drug resistance can be maintained by extrinsic signals, among which exosomes, small vesicles released by (drug-resistant) cells, have been shown to play an important role. The aim of this thesis was to characterize two CML cell lines sensitive and resistant to imatinib, as well as the exosomes derived from imatinib-resistant CML cells by proteomic approaches. Identification of metabolic vulnerabilities in drug-resistant cells enables their targeting by clinically available drugs, thus offering potential therapeutic targets for their selective elimination. Analysis of exosomes derived from imatinib-resistant cells can identify specific membrane surface proteins exploitable as clinically relevant...
|
|
|
Molecular events associated with resistance to tyrosine kinase inhibitors in leukemia cells.
Hrdinová, Tereza ; Vyoral, Daniel (advisor) ; Klener, Pavel (referee) ; Holoubek, Aleš (referee)
Chronic myeloid leukemia (CML) is a myeloproliferative stem cell disease characterized by the expression of BCR-ABL oncoprotein with constitutive tyrosine kinase activity. Although the development of tyrosine kinase inhibitors (TKI) such as imatinib dramatically improved the treatment of CML, a certain subset of patients develops resistance to TKI drugs. The most common cause of TKI resistance are point mutations in the BCR-ABL1 gene, followed by other mutation-independent mechanisms. Survival and proliferation of CML cells in the presence of TKI drugs are accompanied by adaptive changes in their metabolism. Drug resistance can be maintained by extrinsic signals, among which exosomes, small vesicles released by (drug-resistant) cells, have been shown to play an important role. The aim of this thesis was to characterize two CML cell lines sensitive and resistant to imatinib, as well as the exosomes derived from imatinib-resistant CML cells by proteomic approaches. Identification of metabolic vulnerabilities in drug-resistant cells enables their targeting by clinically available drugs, thus offering potential therapeutic targets for their selective elimination. Analysis of exosomes derived from imatinib-resistant cells can identify specific membrane surface proteins exploitable as clinically relevant...
|
|
|
Targeted cancer therapy based on altered metabolism of amino acids
Šafrhansová, Lucie ; Starková, Júlia (advisor) ; Zelenka, Jaroslav (referee)
The effects of targeted therapies in the treatment of cancer have been extensively researched and tested in many clinical trials. In contrast to conventional chemotherapy treatment, targeted therapy should act specifically on cancer cells with limited toxicity and lower risk of side effects. One type of targeted therapy exploits the Achilles heel of cancer - the specificity of tumour metabolism. With knowledge of the metabolic differences between tumor and normal cells, we can set up conditions that normal cells easily bridge, while tumor cells die as a result. This can be achieved by removing certain amino acids from the extracellular environment on which cancer cells depend. A well-known enzyme that has been used therapeutically for many years is asparaginase. However, asparaginase therapy is only successful in some cancers, so further development is needed, as well as the search for enzymes with similar effects. Over the years, four other enzymes that could become an integral part of the treatment of cancer patients in the future have been discovered - arginine deiminase, arginase, methioninase and cyst(e)inase. Past and current studies have investigated their effects on cancer cells in vitro and in vivo. Successful elimination of cancer cells often comes with limitations as immunogenicity and...
|
|
|
The role of new profibrotic molecules in the pathogenesis of systemic sclerosis.
Šumová, Barbora ; Šenolt, Ladislav (advisor) ; Funda, David (referee) ; Soukup, Tomáš (referee)
Systemic sclerosis (SSc) is immune-mediated fibrotic disease of unknown aetiology. Among the dominant pathogenic manifestations of SSc belong vascular changes, production of autoantibodies, activation of innate and adaptive immune responses and fibrotic processes. Transforming growth factor beta (TGF-β) has been identified as a central profibrotic factor stimulating fibroblasts to produce collagen. There are, however, a number of other mediators involved in the pathogenesis of SSc. Mutual activation and amplification of these molecules and their cascades may be a central mechanism of the SSc pathogenesis. Hedgehog (Hh) canonical signalling pathway plays an important role in the development and progression of fibrotic diseases. Expression of Hh target genes can be regulated through a canonical or non-canonical signalling cascade. The non-canonical activation of GLI transcription factors by TGF-β has not yet been investigated in SSc. The substantial part of this thesis is focused on the study of the mutual interaction of TGF-β and Hh signalling pathway. In vitro analysis confirmed TGF- β/SMAD3 dependent activation of GLI2 in dermal fibroblasts. Fibroblasts specific knockout of GLI2 prevented the development of experimental fibrosis in vivo. Combined targeting of canonical and non-canonical Hh...
|
|
|
New ferritin nanoparticles for specific targeting of experimental melanoma in mice: in vitro and in vivo tests.
Rajsiglová, Lenka ; Vannucci, Luca Ernesto (advisor) ; Šírová, Milada (referee)
Cancer diseases represent second most frequent cause of death after cardiovascular diseases in Europe. Nowadays used medical treatments like chemotherapy and radiotherapy are nonspecific and cause huge side effects. Various systems to deliver therapy directly inside the tumour microenvironment and reduce side effects are under development. Protein nanoparticles seem to be very promising strategy to achieve that goal. Our group in cooperation with CNR in Rome tested nanoparticles based on heavy chain of human ferritine. These constructs, modified to expose the tumor targeting molecule, were able to be specifically internalised by B16F10 melanoma cells in vitro. They also specifically target and localise at the sites of primary melanoma and lung metastases of different size in mouse in vivo model. These nanoparticles can carry either therapeutic or diagnostic molecules. Thus they represent a suitable candidate for further studies for potential use in clinical praxis as a diagnostic and/or therapeutic agents (theranostics). Powered by TCPDF (www.tcpdf.org)
|
guest ::
