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Interaction of the anticancer drug lenvatinib with cytochrome P450 subfamily 2C
Srogoň, Jiří ; Dračínská, Helena (advisor) ; Hýsková, Veronika (referee)
Lenvatinib is a multi-targeted kinase inhibitor capable of inhibiting these kinases at nanomolar concentrations. For this reason, it is used as a drug in the treatment of various types of cancer. Like many other xenobiotics, lenvatinib is metabolized by cytochromes P450, which can cause occurrence of drug interactions with other substances. Identification of the most important and clinically relevant drug interactions is essential to ensure the safety of patients already suffering from reduced quality of life due to cancer. The main aim of this bachelor thesis was to investigate the effect of lenvatinib on cytochromes P450, specifically on isoforms of subfamily 2C in humans and rats. The inhibitory effect was measured in vitro using marker rections on rat liver microsome samples for the CYP2C6 isoform and on human recombinant CYP2C9 isoform samples expressed in SuperosomesTM or Bactosomes® . Furthermore, the effect of lenvatinib on CYP2C11 and 2C6 expression in the liver of rats exposed to lenvatinib was investigated. Lenvatinib caused a decrease in the activity of the human recombinant CYP2C9 isoform, whereas no effect was observed on the activity of the CYP2C6 isoform in rat liver microsomes. One of the other objectives was to determine the IC50 for CYP2C9, but the objective was not met. When...
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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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Modulation of cytochrome P450 activity by the anticancer drug lenvatinib
Ivančík, Martin ; Dračínská, Helena (advisor) ; Mrízová, Iveta (referee)
Lenvatinib, commercially marketed as Lenvima®, is an oral drug approved for the treatment of thyroid cancer, hepatocellular carcinoma and renal cell carcinoma that acts as a tyrosine kinase inhibitor. In vitro and in vivo studies have shown that lenvatinib is in the human body metabolised in liver and kidney by the cytochrome P450 enzyme system and aldehyde oxidase. Therefore, the aim of this bachelor thesis was to determine the effect of lenvatinib on the activity of individual isoforms of human cytochrome P450. Among the isoforms studied, those that ensure the metabolism of majority of foreign substances in the human body were selected. Measurements were performed in vitro using recombinant CYPs expressed in SupersomesTM and using marker reactions that are provided by individual cytochrome P450 isoforms. The activity of the enzyme in the reaction mixtures containing lenvatinib was compared with the activity of the enzyme in the reaction mixtures where only the solvent DMSO was added instead of lenvatinib. The concentration of lenvatinib corresponded to the concentration of the given substrate or was 10 times higher. Based on these measurements, the percentage activity of cytochrome P450 isoforms 1A1, 1A2, 1B1, 2B6, 2C8, 2C9, 2E1 and 3A4 in the presence of lenvatinib was calculated. A decrease in...
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Study of effects of tyrosine kinase inhibitors and their metabolites on tumour cell lines
Kolárik, Matúš ; Indra, Radek (advisor) ; Vinklářová, Lucie (referee)
Vandetanib, lenvatinib and cabozantinib are inhibitors of receptor tyrosine kinases approved to treat locally advanced or metastatic thyroid gland, kidney and liver cancers. These multi- kinase inhibitors, inhibit phosphorylation of tyrosine moieties of protein, thus modulate cell signalization in cancer cells. Metabolites of vandetanib, lenvatinib and cabozantinib were detected in vitro as well as in vivo in blood and urine. Cytochromes P450 and flavin monooxygenases were identified as primary enzymes participating in metabolism of these drugs. Literature lacks information regarding pharmacological efficacy of vandetanib, lenvatinib and cabozantinib metabolites. The aim of this diploma thesis was the investigation of pharmacological efficacy of N-oxides of vandetanib, lenvatinib and cabozantinib. The viability measurement under normoxic and hypoxic conditions was employed to determined their efficacy. The expression of enzymes of the first phase of xenobiotics metabolism (CYP 450 1A1, 1B1, 3A4 a CYP 450 oxidoreductase) and receptor tyrosine kinases RET and VEGFR2, as well as mechanism of changes in their expression were investigated using western blotting and flow cytometry. High performance liquid chromatography was utilised to investigate possible metabolism of tyrosine kinase inhibitors and...
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Study of action of anticancer drugs tyrosine kinase inhibitors in a form of nanotransporters
Takácsová, Paulína ; Stiborová, Marie (advisor) ; Černá, Tereza (referee)
Tyrosine kinase inhibitors (TKI) are small organic molecules designed for the targeted cancer therapy. They perform the inhibition of activated receptor tyrosine kinases in tumor cells, that defeats tumor growth, proliferation, metastasis and angiogenesis in tumor tissue. Two TKI, lenvatinib and vandetanib, are used in thyroid cancer treatment. This thesis investigates the ways leading to enhancement of efficiency of these anticancer drugs for therapy. One of the studied anticancer drug - lenvatinib - was investigated to be prepared in a nanoform. Nanoparticles were based on protein apoferritin as well as on lipids. Theoretical model of lenvatinib interaction with an apoferritin cavity, as well as the model of its encapsulation obtained by computer modeling indicated that lenvatinib seems not to be suitable for preparation of apoferritin nanoparticles. Since lenvatinib occurs in its neutral form during preparation of nanoparticles, it does not interact with nanoparticle. The unsuccessful experimental preparation of lenvatinib-loaded apoferritin nanoparticles confirmed that lenvatinib is not suitable for its preparation. However, the theoretical model can serve for screening of other potentially suitable drugs before the experimental nanoparticle preparation. Since the experimental preparation of...
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The effect of tyrosinkinase inhibitors vandetanib and lenvatinib and cytotoxic alkaloid ellipticine on biotransformation enzymes
Baráčková, Petra ; Dračínská, Helena (advisor) ; Václavíková, Radka (referee)
In recent years, tyrosine kinase inhibitors have been widely used for the treatment of certain tumors as so-called targeted therapy. Many studies are concerned with their metabolism and the role of enzymes in the biotransformation process, but very little is known about the impact of tyrosine kinase inhibitors on the expression and activity of biotransformation enzymes. Nevertheless modification of the expression and activity of enzymes may cause adverse interactions of co-administered drugs and their negative impact on the human body. This diploma thesis studies the effect of tyrosine kinase inhibitors vandetanib and lenvatinib and cytotoxic alkaloid ellipticine on biotransformation enzymes in a rat model organism in vivo. The aim was to characterize the effect of the investigated compounds on gene expression, protein expression and activity of cytochromes P450 (CYP) 1A1, 1A2 and 1B1 and flavin-containing monooxygenases FMO1 and FMO3 in renal and hepatic microsomes. Microsomes and RNA were isolated from kidneys of control rats and the pretreated rats. Western blot and immunodetection was used to compare the protein expression levels of studied enzymes in kidney and liver. By reverse transcription, cDNA was prepared from isolated RNA and used as a template for quantitative PCR to compare the...
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The inhibitors of tyrosine kinases and their effect on the expression of biotransformation enzymes
Dvořák, Josef ; Dračínská, Helena (advisor) ; Moserová, Michaela (referee)
Tumor diseases are one of the most common causes of death in the human population. One of the many possible causes of tumor growth is abnormal function of tyrosine kinases, which are involved in signal transfer and regulation of the most important cell processes. These processes include the control of cell growth, division and cell differentiation and apoptosis. For the therapy of tumor diseases caused by the abnormal function of tyrosine kinases, their specific inhibitors are developed. For the targeted treatment of thyroid tumors, the tyrosine kinases vandetanib and lenvatinib are newly used. In this bachelor thesis, the effect of vandetanib and lenvatinib on the gene expression of the cytochrome P450 family of 2 (CYP2A2, CYP2B1, CYP2C11, CYP2D1, CYP2E1) biotransformation enzymes has been investigated as they are involved in the biotransformation reactions of a large portion of the available drugs on the market. To examine the relative gene expression of CYP2, quantitative PCR of samples of cDNA, synthesized from isolated RNA from rat liver and kidney exposed to the above-mentioned tyrosine kinase inhibitors, was used. The results suggest, that vandetanib and lenvatinib do not have a significant effect on the gene expression of cytochrome P450 family 2 in rat liver and kidney tissue. KEY WORDS:...
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Metabolism of an inhibitor of tyrosine kinase lenvatinib as the anticancer drug with targeting effects
Vavrová, Katarína ; Stiborová, Marie (advisor) ; Kubíčková, Božena (referee)
Lenvatinib is an oral anticancer drug that belongs to a group of tyrosine kinases, which block signal pathway receptors for development and proliferation of various cancer diseases. Lenvatinib was approved in 2015 for a treatment of progressive, locally spread or metastatic, differentiated thyroid cancer refractory to radioiodine treatment. This thesis presents findings about the metabolism of lenvatinib and identification of enzymes responsible for biotransformation of this drug. Utilizing human and rat hepatic microsomes as well as recombinant cytochromes P450 (CYPs) expressed in SupersomesTM , the metabolism of lenvatinib was studied. Used rat microsomal systems were isolated from the liver of uninduced rats and from the liver of rats in which expression of individual CYPs was induced by CYP inducers. The lenvatinib metabolites were separated by HPLC and identified by mass spectroscopy. Using rat microsomal systems, O-desmethyllenvatinib and lenvatinib N-oxide were produced. The highest amount of these lenvatinib metabolites was produced by microsomes of rats pretreated with pregnenolone carbonitrile that is an inducer of CYP3A. Human hepatic microsomes oxidize lenvatinib to O-desmethyllenvatinib and N-descyklopropyllenvatinib. In the case of rat recombinant CYPs, O-desmethyllenvatinib was...
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The effect of vandetanib, lenvatinib and ellipticine on the expression of rat cytochromes P450 1A and 3A
Jelínková, Sandra ; Dračínská, Helena (advisor) ; Žáková, Lenka (referee)
In recent years, the inhibiition of tyrosine kinases,which may incorrectly regulate some singaling pathway has been used to treat cancer as so-called biological therapy. An example of such inhibitors are vandetanib and lenvatinib. These two substances are used to treat thyroid gland tumors because they affect vascular growth factor receptor or endothelial growth factor receptor that can regulate tumor growth and metastasis. Ellipticine, which has anti-tumor effects on lots of tumor disease, has been investigated in this study together with vandetanib and lenvatinib. In this diploma thesis, the effect of mentioned tyrosine kinase inhibitors, ellipticine and their combinations on gene and protein expression of CYP1A1, 1A2, 3A1 and 3A2 in rat liver in vivo was determined. Protein expression was studied using Western blot method with imunodetection. Gene expression was assessed by quantitative PCR. Moreover, the effect of tested substances and their combinations on CYP1A activity (measured as 7-ethoxyresorufin O-deethylation), CYP1A2 activity (measured as 7-methoxyresorufin O-demethylation), CYP1A1 activity (measured as Sudan I oxidation), CYP3A specific activity (measured as testosteron 6β-hydroxylation) and ellipticine, vandetanib, lenvatinib metabolism was determined. It has been confirmed that...
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