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Study on the role of selected cytochrome P450 isoforms in cytostatic resistance at apoptosis level
Moriová, Magdalena ; Hofman, Jakub (advisor) ; Novotná, Eva (referee)
Charles University Faculty of Pharmacy in Hradci Králové Departement of Pharmacology & Toxicology Student: Magdalena Moriová Supervisor: RNDr. Jakub Hofman, Ph.D. Title of diploma thesis: Study on the role of selected cytochrome P450 isoforms in cytostatic resistance at apoptosis level Cytostatic resistance is one of the most problematic obstacles in oncological treatment. Beside pharmacodynamic mechanisms, pharmacokinetic factors play an important role in drug resistance as well. Enzymatic transformation of active substance to inactive metabolite in tumor cells probably belongs to these mechanisms, however, evidences concerning the relevance of this phenomenon are predominantly either indirect and/or affected by interference elements. Using comparative experiments with HepG2 cell lines with/without CYP3A4 overexpression, we focused on the evaluation of the role of this clinically important enzyme in the resistance against docetaxel. Methodologically, it was the assessment of apoptosis induction (activation of caspases 3/7, 8 and 9) using commercial luminescent kits. Our results suggest significant participation of CYP3A4 enzyme on the reduction of docetaxel anticancer efficacy after 48 h from treatment, whereas this effect was not recorded in earlier intervals. These findings perfectly correlate...
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Study on interactions of PARP inhibitors with ABC drug efflux transporters
Dziaková, Lucia ; Hofman, Jakub (advisor) ; Čečková, Martina (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Lucia Dziaková Supervisor: RNDr. Jakub Hofman, Ph.D. Title of diploma thesis: Study on interactions of PARP inhibitors with ABC drug efflux transporters. ATP-binding cassette (ABC) transporters are integral membrane proteins that use the energy obtained from ATP to carry transport of numerous endogenous substrances out of the cells, but attention is drawn primarily to the fact that they transfer also xenobiotics. Their overexpression in tumor tissue contributes to multidrug resistance (MDR), which in most cases leads to therapy failure. Poly(ADP-ribose)polymerase inhibitors (PARPi) represent a promising therapeutic approach in the treatment of cancers that exhibit defects in homologous recombination (HR). This work focuses on four selected PARPi (olaparib, rucaparib, niraparib, veliparib) and their interaction potential towards ABC drug efflux transporters (ABCB, ABCC1, ABCG2). In our work, we worked with MDCKII cells (parent, transduced by the transporters of interest) and utilized the principle of accumulation studies based on the measurement of fluorescence intensity of specific model substrates (hoechst33342, calcein AM, daunorubicin, mitoxantrone). We used established inhibitors of studied...
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Comparison of platelet aggregation in healthy population.
Minarovičová, Júlia ; Mladěnka, Přemysl (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Júlia Minarovičová Supervisor: prof. Přemysl Mladěnka, Pharm.D., Ph.D. Title of diploma thesis: Comparison of platelet aggregation in healthy population Platelets have an irreplaceable role in the process of aggregation. Nevertheless, their increased activity is associated with the development of many cardiovascular diseases. This process can be influenced by clinical used substances from the group of antiplatelet drugs, which differ in their effectiveness within the population. Within this study, platelet aggregation was tested using impedance aggregometry, whose principle is the change in electrical impedance between electrodes caused by the adhesion of activated platelets. Firstly, whole blood was incubated with clinically used antiplatelet drugs (ticagrelor, vorapaxar, and acetylsalicylic acid) and a flavonoid metabolite, 4-methylcatechol. Subsequently, a platelet aggregation inducer (ADP, thrombin receptor activating peptide 6 /TRAP/, collagen, arachidonic acid, ristocetin, U-46619, and platelet-activating factor /PAF/) was added, and the process was monitored for 6 minutes. The most potent inhibitor of the aggregation induced by arachidonic acid was acetylsalicylic acid in a concentration of 70 μM...
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The use of selected inhibitors to overcome anthracycline resistance in cancer therapy (in vitro study).
Tučková, Kateřina ; Wsól, Vladimír (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Kateřina Tučková Supervisor: prof. Ing. Vladimír Wsól, Ph.D. Consultant: Mgr. Lenka Laštovičková, Ph.D. Title of diploma thesis: The use of selected inhibitors to overcome anthracycline resistance in cancer therapy (in vitro study) Resistance to chemotherapy is a severe problem in treating cancer patients, significantly reducing their chances of recovery. The increased expression of carbonyl reductases in tumour cells is one of the leading causes of the resistance. These enzymes can reduce anthracycline-based chemotherapy drugs to their less effective derivatives and thus significantly reduce their efficiency. Therefore, the inhibitors of carbonyl reductases could increase the effectiveness of anthracycline-based chemotherapy. The goal is to find an inhibitor with high inhibitory activity and low side effects. This thesis tested inhibitors asciminib, tucatinib, sotorasib, and umbralisib hydrochloride against carbonyl reductases from the aldo-keto reductase superfamily (AKR1C3, 1A1, 1B1, 1B10) and short-chain dehydrogenases/reductases superfamily (CBR1), using chemotherapy drug daunorubicin. The most significant inhibitory potential was observed between asciminib and the enzyme AKR1C3,...
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Study of pharmacokinetic and pharmacodynamic mechanisms of drug resistance and their modulation in non-small cell lung cancer
Zhang, Yu ; Hofman, Jakub (advisor) ; Pešek, Miloš (referee) ; Trejtnar, František (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Training Workplace Department of Pharmacology and Toxicology Doctoral Degree Program Pharmacology and Toxicology Candidate Yu Zhang Supervisor Assoc. Prof. RNDr. Jakub Hofman, Ph.D. Advisor Title of Doctoral Thesis Study of pharmacokinetic and pharmacodynamic mechanisms of drug resistance and their modulation in non-small cell lung cancer Lung cancer represents one of the most threatening malignancies, which is attributed by its leading morbidity and mortality among all cancer types. Pharmacological interventions have played impressive roles in the clinical management of non-small cell lung cancer (NSCLC) with the outstanding improvements on patients' survival. Nevertheless, the inevitable emergence of drug resistance severely diminishes their efficacies. Traditional chemotherapeutic drugs have been introduced in the treatment of NSCLC decades ago. Countless studies showed that the emergence of multidrug resistance (MDR) is deeply associated with two pharmacokinetic factors: (1) increased drug efflux via ATP-binding cassette (ABC) transporters and (2) enhanced drug deactivation by biotransformation enzymes, e.g., cytochromes P450 (CYPs). Previously, we and others have demonstrated that several novel targeted agents can synergistically...
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Study of novel phthalocyanine photosensitizers on cellular level
Halašková, Marie ; Macháček, Miloslav (advisor) ; Pejchal, Jaroslav (referee) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Mgr. Marie Halašková Supervisor: RNDr. Miloslav Macháček, Ph.D. Title of disertation thesis: Study of novel phthalocyanine photosensitizers on cellular level Photodynamic therapy (PDT) is a clinically approved treatment modality that experienced great progress over the last two decades and that has been used in the treatment of several disorders, including age-related macular degeneration, psoriasis and certain cancers. PDT is based on the combination of three main components: light-sensitive drug (known as a photosensitizer, PS), light of an appropriate wavelength, and oxygen. The light-activated PS reacts with molecular oxygen to produce reactive oxygen species, which can interact with cellular components in a biological environment and trigger a cascade of reactions causing destruction of tumor cells, tumor vasculature and induction of a local inflammatory reaction. The result is a disruption of cell homeostasis leading to the cell death. Like all the novel treatment modalities, further research is still needed including the development and optimization of PS synthesis in order to increase the efficiency of therapy and minimalize side effects. In this project, we decided to carry out an...
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Comparison of platelet aggregation in healthy population.
Minarovičová, Júlia ; Mladěnka, Přemysl (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Júlia Minarovičová Supervisor: prof. Přemysl Mladěnka, Pharm.D., Ph.D. Title of diploma thesis: Comparison of platelet aggregation in healthy population Platelets have an irreplaceable role in the process of aggregation. Nevertheless, their increased activity is associated with the development of many cardiovascular diseases. This process can be influenced by clinical used substances from the group of antiplatelet drugs, which differ in their effectiveness within the population. Within this study, platelet aggregation was tested using impedance aggregometry, whose principle is the change in electrical impedance between electrodes caused by the adhesion of activated platelets. Firstly, whole blood was incubated with clinically used antiplatelet drugs (ticagrelor, vorapaxar, and acetylsalicylic acid) and a flavonoid metabolite, 4-methylcatechol. Subsequently, a platelet aggregation inducer (ADP, thrombin receptor activating peptide 6 /TRAP/, collagen, arachidonic acid, ristocetin, U-46619, and platelet-activating factor /PAF/) was added, and the process was monitored for 6 minutes. The most potent inhibitor of the aggregation induced by arachidonic acid was acetylsalicylic acid in a concentration of 70 μM...
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Expression of ABC transporters in cell cultures of non-small cell lung cancer: effect of selected targeted drugs
Žofajová, Barbora ; Hofman, Jakub (advisor) ; Červený, Lukáš (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Barbora Žofajová Supervisor: doc. RNDr. Jakub Hofman, Ph.D. Title of diploma thesis: Expression of ABC transporters in non-small cell lung carcinoma cell cultures: effect of selected targeted drugs ABC transporters form a special family of transmembrane proteins, their function is the active efflux of substrates into the extracellular environment. These transporters are expressed in normal tissues and tumor cells. Thus, they influence drug pharmacokinetics and play a role in the development of multidrug resistance (MDR). Tyrosine kinases have essential functions ranging from proliferation to differentiation and cell death, their mutation can cause carcinogenesis. Finding, exploring, and inhibiting the functions of these targets is a promising strategy to treat cancer. This work aimed to determine whether the selected drugs are involved in pharmacokinetic interactions that are based on inductions of ABC efflux transporter genes and whether they have the potential to affect MDR phenotype of tumor cells. The drugs, which we studied, were three targeted anticancer drugs (capmatinib, pralsetinib, and tazemetostat) and two well- known chemotherapeutic drugs (pemetrexed and methotrexate). First, we...
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Study on the effect of selected targeted drugs on drug resistance mediated by ABC drug transporters
Paulusová, Viktória ; Hofman, Jakub (advisor) ; Novotná, Eva (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Viktória Paulusová Supervisor: doc. RNDr. Jakub Hofman, Ph.D. Title od diploma thesis: Study on the effect of selected targeted drugs on drug resistance mediated by ABC drug transporters. Multidrug resistance (MDR) is one of the major problems associated with cancer treatment. A key determinant of MDR is increased efflux of drugs through membrane ATP- binding cassette (ABC) transporters, which are a family of transporter proteins. Their overexpression contributes to MDR by decreasing intracellular drug concentration due to the efflux of various drugs from cells. Targeting ABC transporters appears to be a promising approach to suppress drug resistance. Therefore, one strategy to reverse the resistance of ABC transporter-expressing tumor cells is the combined use of chemotherapeutic drugs with ABC transporter modulators to enhance therapeutic efficacy. The aim of this work was to investigate the effect of targeted drugs (capmatinib, pralsetinib and tazemetostat) in combination with cytostatics (etoposide and topotecan) on drug resistance mediated by ABC efflux transporters. Results were obtained using MTT assays and caspase activity assays performed on the parental A431 cell line and its...
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The use of selected inhibitors to overcome anthracycline resistance in cancer therapy (in vitro study).
Tučková, Kateřina ; Wsól, Vladimír (advisor) ; Hofman, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Kateřina Tučková Supervisor: prof. Ing. Vladimír Wsól, Ph.D. Consultant: Mgr. Lenka Laštovičková, Ph.D. Title of diploma thesis: The use of selected inhibitors to overcome anthracycline resistance in cancer therapy (in vitro study) Resistance to chemotherapy is a severe problem in treating cancer patients, significantly reducing their chances of recovery. The increased expression of carbonyl reductases in tumour cells is one of the leading causes of the resistance. These enzymes can reduce anthracycline-based chemotherapy drugs to their less effective derivatives and thus significantly reduce their efficiency. Therefore, the inhibitors of carbonyl reductases could increase the effectiveness of anthracycline-based chemotherapy. The goal is to find an inhibitor with high inhibitory activity and low side effects. This thesis tested inhibitors asciminib, tucatinib, sotorasib, and umbralisib hydrochloride against carbonyl reductases from the aldo-keto reductase superfamily (AKR1C3, 1A1, 1B1, 1B10) and short-chain dehydrogenases/reductases superfamily (CBR1), using chemotherapy drug daunorubicin. The most significant inhibitory potential was observed between asciminib and the enzyme AKR1C3,...
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