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Study of the binding interaction of tyrosine kinase inhibitors with serum albumin
Rodová, Marie ; Indra, Radek (advisor) ; Heidingsfeld, Olga (referee)
Sunitinib and vandetanib are anti-cancer medications prescribed for medullary thyroid cancer (in the case of vandetanib) and for renal cell carcinoma, gastrointestinal stromal tumor, and pancreatic cancer (in the case of sunitinib). They belong to the group of tyrosine kinase inhibitors and act by exhibiting anti-angiogenic effects and by inhibiting tumor cell proliferation and survival through VEGFR. Additionally, vandetanib also inhibits tumor cell survival via EGFR and RET. In the presented thesis, we investigated the binding interaction between serum albumin and the TKIs vandetanib and sunitinib using BSA, HSA, and blood plasma. We examined the differences in interaction between the TKIs and various serum albumins, including pure BSA, pure HSA, and blood plasma, as well as the nature and location of the binding interaction. Additionally, we studied the influence of other ligands on this interaction and the photosensitivity of sunitinib itself. Utilizing spectroscopic techniques, including UV-VIS absorption and fluorescence quenching, we have determined the Stern-Volmer and binding constants, as well as the thermodynamic parameters, for the binding interactions of sunitinib and vandetanib with BSA and HSA. Our results indicate that complex formation occurs between BSA and sunitinib, BSA and...
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Effect of pH and other factors on the metabolic conversion of tyrosine kinase inhibitors.
Čillíková, Olívia ; Indra, Radek (advisor) ; Čermáková, Michaela (referee)
Targeted anti-tumor therapy is a modern and effective approach to cancer treatment. This type of therapy includes several groups of anticancer drugs. The second most commonly used group of targeted chemotherapeutic substances are tyrosinkinase inhibitors. These are small- molecular agents that target specific signalling pathways of the tumor cell, thereby inhibiting it's growth, proliferation and angiogenesis. Representatives of this drug group include vandetanib and sunitinib. Vandetanib is primarily used for the treatment of medullary thyroid cancer and sunitinib has been approved for the treatment of gastrointestinal stromal tumor and advanced renal cell carcinoma. The diploma thesis focuses on the effect of pH and temperature on the in vitro metabolism of vandetanib and sunitinib using first-phase biotrasnformation enzymes. Differently premedicated and control rat liver microsomes were used in the experiments. Human and rat recombinant cytochromes P450 were used for comparison. The primary purpose of the experiments was to find the experimental pH and temperature optimum of the in vitro metabolism of vandetanib and sunitinib. These experiments also investigated the effect of pH and temperature on the drugs themselves and their stability. The effect of pH and temperature on the metabolism of the...
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Molecular Biomarkers of Anticancer Drugs Efficacy in Experimental Models and in Patients with Solid Tumors
Šeborová, Karolína ; Václavíková, Radka (advisor) ; Mohelníková Duchoňová, Beatrice (referee) ; Indra, Radek (referee)
Ovarian carcinoma is a heterogeneous group of diseases usually of epithelial origin. The vast majority of diagnosed cases are high-grade serous carcinomas, which account for over 80% of all cases. Ovarian carcinoma is one of the most common causes of death in women from gynecological malignancies. The main cause of high mortality is diagnosis of the disease in late stages due to the long-term asymptomatic course. The second important cause is the development of multidrug resistance to the administered treatment, which is in the case of ovarian carcinoma patients still mainly based on a combination of paclitaxel and platinum derivatives - cisplatin or carboplatin. These are some of the reasons that motivate scientists to search for new biomarkers, which could help detect the disease in early stages, or monitor the success of treatment, and predict the development of resistance. Molecular characterization of cancer in general may also reveal new therapeutic targets. The development of resistance to already existing drugs stimulates the direction of scientists to prepare new drugs that would be especially effective against already resistant tumors. The main aim of the presented theses was to expand information on the molecular profile of ovarian carcinoma, to reveal prognostic and predictive molecular...
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Study of metabolism of tyrosine kinase inhibitors and mechanism of their anticancer effects
Vavrová, Katarína ; Indra, Radek (advisor) ; Souček, Pavel (referee) ; Ječmen, Tomáš (referee)
As inhibitors of tyrosine kinases have become more widely used in anticancer therapy, detailed understanding of their pharmacokinetic profile is increasingly essential for the improvement of treatment outcomes. Herein, the metabolism in liver microsomes in animal models and humans was studied. Clarification of which liver enzymes, specifically cytochromes P450 (CYP), are involved in the metabolism of vandetanib, cabozantinib and, lenvatinib, may play a key role in oncology practice, as these anticancer drugs are administrated in combination with other drugs. This co-administration may pose a risk of drug interactions, which may result in decreased efficacy or increased drug-related toxicity. To elucidate the metabolism of our selected anticancer drugs in human liver, the same approaches were gradually used- correlation analysis using human liver microsomes from 12 different donors, inhibition studies, and the use of recombinant CYP. In addition, an approach with animal liver microsomes that were premedicated with inducers of individual CYP was used to elucidate vandetanib metabolism in rat liver. Our first studied tyrosine kinase inhibitor was vandetanib. In the first paper, we studied its metabolism in humans through various approaches, and subsequently in another publication in rat. The...
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The role of glutathione in the metabolism of plants exposed to environmental contaminants.
Rychnová, Andrea ; Hýsková, Veronika (advisor) ; Indra, Radek (referee)
Environmental contamination by pharmaceuticals is currently occurring at an unsustainable rate. It is in the public interest that xenobiotics, which enter not only wastewater but also groundwater and drinking water, are removed from the contaminated environment in an efficient and environmentally sound manner. A promising method is phytoremediation, which can meet the requirements. Another contemporary issue is the increasing scarcity of water and the related question of whether it is possible to recycle wastewater and use it for irrigating crops. How plant metabolism responds to pharmaceuticals can be elucidated by biomarkers of oxidative stress caused by xenobiotics. These include the activity of enzymes associated with the detoxification and antioxidant systems of plants. In this work, the effect of currently increasingly used antidepressants (buspirone, sulpiride and paroxetine) was investigated in maize (Zea mays L., DKC 3969) plants grown under sterile conditions in vitro. The work was focused on enzymes related to glutathione metabolism and on ascorbate peroxidase (APX). In plant leaves, the activity of glutathione-S-transferase (GST), a conjugating enzyme of phase II biotransformation of xenobiotics, was increased by all drugs. In addition, a drug-inducible isoform of GST was detected by...
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Nanoforms of cabozantinib - preparation and characterisation
Fürbacherová, Pavlína ; Indra, Radek (advisor) ; Mrízová, Iveta (referee)
Cancer diseases belong among most serious problems of modern medicine, after cardiovascular problems. In connection with finding the solution of this problem, in recent years there was a development of so-called targeted therapy, which uses nanoparticles in the treatment, which are supposed to make the treatment more effective. One of nanoparticles used in the targeted therapy, is apoferritin, which is naturally occurring transport and storage protein in the human body. Apoferritin has a cavity in its structure, into which a cytostatic agent can be incorporated. In addition, its structure is strongly dependent on the pH value, which makes the incorporation and the subsequent release of the drug in the desired location easily impressionable. These properties make apoferritin a suitable potential nanotransporter. The drug studied in this thesis is the cytostatic drug called cabozantinib. It's tyrosinkinase inhibitor, used in the treatment of advanced metastatic medullary thyroid carcinoma, hepatocellular carcinoma and refractory renal carcinoma. In this thesis, the preparation of cabozantinib complex incorporated in apoferritin was optimized, and subsequently the release of the drug from apoferritin and the metabolism of this complex were monitored using liver microsomes and cytochromes. The results...
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Effect of rat enzymes on the metabolism of tyrosine kinase inhibitors in vitro and in vivo
Škriabová, Simona ; Indra, Radek (advisor) ; Ptáčková, Renata (referee)
Tyrosine kinase inhibitors are small molecules, orally available, well-tolerated and globally approved drugs for the treatment of several types of tumors. These drugs include vandetanib, cabozantinib, and lenvatinib, which are used to treat thyroid cancer. Vandetanib and cabozantinib are drugs approved for the treatment of medullary thyroid cancer, and lenvatinib is approved for the treatment of differentiated thyroid cancer. In the presented diploma thesis, the in vitro and in vivo metabolism of vandetanib, cabozantinib and lenvatinib was studied. Microsomes isolated from the liver of rats premedicated with pregnenolone carbonitrile were used to study in vitro metabolism. Plasma and urine samples of rats premedicated with individual tyrosine kinase inhibitors were used to study in vivo metabolism. The resulting metabolites were analyzed by high-performance liquid chromatography and subsequently identified using the mass spectrometry method. In the study of in vitro metabolism, when NADPH and cofactors (glucuronic acid and glutathione) were added to the samples, it was found that the most metabolites appeared for all three drugs during a longer incubation periods, and at the same time, it was found that glucuronic acid and glutathione can influence the structure, properties and functions of the...
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Preparation of mitotic inhibitors in the form of nanotransporters
Meskařová, Veronika ; Indra, Radek (advisor) ; Hýsková, Veronika (referee)
Cancer is one of the most widespread diseases that every third person will encounter it. It is a disease arising from the sudden growth and rapid division of own cells. Despite progress in treatment, an effectiveness is not sufficient, and cancer is the second most common cause of death. In addition, the treatment is associated with several side effects. Currently nanomedicine uses nanomaterials for transport drugs in cancer treatment. It is possible to deliver the drug to the target site, but also to reduce the systemic toxicity of the drug by binding the drug to a suitable nanotransporter. This diploma thesis deals with seeking the appropriate mass ratio of antitumor drugs, colchicine and docetaxel, and the nanotransporter apoferritin. The aim was to find suitable in vitro conditions for high drugs encapsulation into the nanotransporter. Drugs encapsulation took place under active and passive conditions. Active encapsulation was under way on opening and closing nanotransporter by changing pH environment in test tube. Drugs were dissolved in DMSO or water with addition of HCl to charge the drug molecules and improve the binding of the drug into nanotransporter. As part of passive encapsulation, drugs were incubated in surroundings of urea or bivalent metal ions. Overall, it can be concluded that...
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Metabolism of benzo [a] pyrene by the lung cells of a patient with cystic fibrosis
Skořepová, Adéla ; Indra, Radek (advisor) ; Wilhelm, Marek (referee)
Cancer is the most common disease, killing several million people worldwide each year. There are many reasons for its occurrence. The most common causes of cancer include alcohol and tobacco use. Nowadays, there is also a higher incidence of physical and chemical carcinogens that interfere with the environment. Poor eating habits and lack of exercise are also influential. Nowadays, thanks to good medical care, improved diagnostics and, above all, a number of existing vaccines, cancer is partly preventable. In the future, it is safe to say that cancer will increase. According to the IARC, over 19.3 million new cases will be diagnosed worldwide in 2020. By 2040, it is estimated that there will be another 10.9 million. Cystic fibrosis is an autosomal recessive inherited disease that affects 1 in 2500 newborns in the population. The main cause is impaired function of the CFTR protein as a transmembrane regulator of cystic fibrosis, leading to impaired fluid transport and impermeability of chloride ions, with a combination of excessive sodium absorption, leading to reduced water content in the periciliary fluid. People with cystic fibrosis are much more susceptible to colon cancer, especially those who have undergone lung transplantation. In recent years, the treatment of patients with cystic fibrosis...
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Metabolism of the mitotic inhibitor BTB-1 by first phase biotransformation enzymes
Vančurová, Kateřina ; Indra, Radek (advisor) ; Martináková, Lenka (referee)
Cancer is still one of the most common deaths in the world and therefore new drugs are needed to be developed to stop or slow down this disease. Recently, there has been a huge expansion in drug development. Cytostatics that are still widely used include a group of mitotic inhibitors aimed at inhibiting mitosis. A representative of a mitotic inhibitor is the small newly discovered molecule BTB-1. This molecule mediates reversible inhibition of the molecular motor Kif18A, which plays an important role in cell division. In the first part of this presented bachelor thesis, a suitable method for the determination of BTB-1 using high performance liquid chromatography was developed and subsequently its sensitivity was verified. Furthermore, a suitable extracting reagent was found. In the second part of the bachelor thesis, the metabolism of BTB-1 was studied by the microsomal system of non-premedicated rats and rats premedicated with various cytochrome P450 inducers. Subsequently, the time dependence of BTB-1 conversion was studied by the microsomal system of premedicated rats. The effect of different concentrations of BTB-1 on its metabolism was also studied using the microsomal system of premedicated rats. Furthermore, the metabolism of this new molecule was studied using cytosolar systems isolated...
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