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Molecular mechanisms of apoptosis induced by photodynamic activation in cancer cells
Moserová, Irena ; Králová, Jarmila (advisor) ; Kuželová, Kateřina (referee) ; Kovář, Jan (referee)
Photodynamic therapy (PDT) is a treatment modality for cancer. It combines selective accumulation of chemical compounds, called photosensitizers (PS), with light to irreversibly damage cancer cells via oxidative stress. The main goal of this thesis was to study photosensitizers represented by a unique group of newly synthesized porphyrin derivatives with glycol chain substitution. Glycol-functionalized porphyrins containing one to four low molecular weight glycol chains that are linked via ether bonds to the meta-phenyl positions of meso-tetraphenylporphyrin (mTPP(EG)1-4) were compared with fluorinated (pTPPF(EG)4) and nonfluorinated (TPP(EG)4) derivatives having glycol chains in para-phenyl positions. The cellular uptake and photodynamic activity was significantly dependent on terminal groups of the glycol substituent. Hydroxy glycol porphyrins, in contrast with methoxy glycol porphyrins, exhibited efficient intracellular transport and high induction of apoptosis in tumor cell lines in vitro. After initial testing effective prototype hydroxy ethylene glycol derivatives were selected and analyzed in detail. Para derivatives pTPP(EG)4 and pTPPF(EG)4 accumulated mainly in lysosomes whereas meta derivatives mTPP(EG)1-4 in the endoplasmic reticulum (ER). Position of ethylene glycol chain on the...
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Apoptosis Signating Pathways and Biological Effects of TGFB
Šimáková, Olga ; Fuchs, Ota (advisor) ; Brdička, Radim (referee) ; Holada, Karel (referee)
Apoptosis is necessary for maintaing the integrity of all alive multicellular organisms and therefore needs to be precisely regulated. Very important regulators of apoptosis are pleiotropic cytokines from TFGβ superfamily (e.g. TGFβ, BMP, aktivins), whose signals are transduced by SMAD proteins. Patients with secondary myelodysplasias and acute myeloid leukemias (MDS/AML) frequently exhibit interstitial deletions of the chromosome-5q resulting in hemizygous loss of the transcription transactivator SMAD5. SMAD5 is a member of the signal transducer family conveying the pleiotropic TGFβ/BMP cytokine signals with roles in development, cell growth control, and tumor progression. Consistent Smad5 gene expression in these cell types and the gradual increase in its mRNA and protein levels in a model of induced erythroid differentiation of murine erythroleukemia (MEL) cells suggest a role of the gene in hematopoiesis. We show that bone morphogenetic protein 4 (BMP4) directs Smad5 activation in human hematopoietic cells, as monitored at the levels of protein phosphorylation, nuclear translocation, and specific transcription response. In vitro induction of normal human CD34+ cells by BMP4 results in significantly increased proliferation of erythroid progenitors (BFU-E) and formation of glycophorin- A+ cells, whereas...
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Action of polyomavirus protein in host cell cycle
Suchanová, Jiřina ; Král, Jiří (referee) ; Drda Morávková, Alena (advisor)
The polyomaviruses belong to a class of small DNA viruses that are capable to induce tumor growth within the cells infected by the virus. The course of their life cycle is entirely dependent on utilization of the infected cell mechanisms that have to be very precisely regulated. Above all, this thesis concentrates on investigating the factors that influence the course of the infected cell cycle, and also the ways in which the virus is able to interact with its control mechanisms. The polyomavirus early transcripts (T-antigens) have a main impact on the progression of the individual phases of the cell cycle. The biggest T-antigen (so called "Large T-antigen") is responsible for both the interaction with the main regulators of the cell cycle (proteins p53 and pRB) and a viral replication, immortalization of the cell and blocking of the mitotic phase of the cell cycle. The mitosis is very unfavorable to the virus because it utilizes a great amount of limited material of the cell organism that the virus needs for its own replication. According to the latest research the virus induces several changes within the cell cycle. For example, it creates a second S phase instead of the mitotic phase in the cell. It causes the accumulation of the infected cells in the late G2 phase as opposed the accumulation of...
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Model of experimentally regulated expression of dipeptidylpeptidase IV in glioma cell lines
Trylčová, Jana
Model of experimentally regulated expression of dipeptidyl peptidase IV in glioma cell lines Abstract "Dipeptidyl peptidase IV Activity and/or Structure Homologues" (DASH) represent a newly defined group of multifunctional molecules, typically bearing dipeptidyl peptidase IV- like hydrolytic activity. Dipeptidyl peptidase IV (DPPIV, EC 3.4.14.5, identical to CD26) cleaves out X-Pro dipeptides from the N-terminus of peptides. Recent knowledge shows substantial role of DASH in cancer pathogenesis. Here we present (i) an overview of the issue of DASH molecules and their functional substrates in the neuroectodermal tumor and (ii) a preparation of stable transfected human glioblastoma cell lines with inducible gene expression of DPPIV. Vectors containing human DPPIV gene and its mutated form in the catalytic active site have been prepared to assess the importance of the enzymatic activity of the final product. This will enable us to study the biological role of DPPIV in genesis and progression of neuroectodermal tumors - cells growth, invasion and migration of transformed glial cells in vitro. Moreover, complex role of DPPIV will be studied using a model of homotopic application of transfected cells into the brain of immunodeficient mice. Prepared cell lines provide more consistent information about DPPIV from...
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Secondary tumors after irradiation for carcinoma of the breast
SUKOVÁ, Denisa
One of the most common cancers in women is breast cancer. The incidence of breast cancer is great and its incidence increases after 50 years of age. In 2009, 5,975 women were newly diagnosed. Despite the fact that the treatment of breast cancer, especially in its early stages, is very successful, breast cancer still remains the leading cause of cancer death in women. In 2009, 1,607 women succumbed to this pestilential disease. The main treatment modality is surgical treatment. Breast cancer is moderately chemosensitive and radiosensitive, which suggests a potential treatment using chemotherapy and radiotherapy. Other treatment modalities include hormonal and biological therapies. Radiotherapy is a medical discipline that uses ionizing radiation to treat malignant as well as benign diseases. When applying ionizing radiation, tolerance doses of organs and tissues must be observed. As a result of exceeding the tolerance doses, significant changes and complications reducing the quality of life arise. Because the survival rate of cancer patients is increasing, the study of late effects of cancer treatment is becoming more important. One of the serious late side effects is the formation of secondary tumour. The practical part of the thesis focuses on the issues of radiation-induced tumours in women who have been treated with radiotherapy for breast cancer. The research group consists of patients who were exposed to radiation at a hospital in České Budějovice between 2000 and 2004. The entire group included 516 patients who were exposed to radiation aimed to the breast or chest wall. I monitored in these patients the eventual formation of a duplicate tumour, its location, type, and latency time. I also focused on the calculation of relative risk. After the completion of radiation therapy, a secondary tumour formed in 32 patients, i.e. 6.2 %. Two new tumours were found in one of the patients, the total of 33 secondary tumours was diagnosed. The most frequent types of newly formed tumours were cancers of contralateral breast and non-melanoma skin cancers (basal cell epithelioma). Both tumour types were represented in the number of seven. Furthermore, six lung tumours, three rectal tumours, and two cases of cervical, kidney and bladder tumours were found. In addition, a duplicate tumour of the brain and the meninx, a myeloma, a thyroid tumour, and an endometrial tumour were found. 58 % cases of duplicate tumours were located outside the irradiated areas. Four of the six newly formed lung tumours, three of the seven newly formed skin tumours, and seven tumours in the contralateral breast were identified in the irradiated areas. Latency time till the formation of duplicate tumours ranged from two to twelve years. The median of the latency time was seven years. Within five years after irradiation a total of 14 secondary tumours formed, i.e. 42 % of the total. Within ten years after irradiation most of the duplicate tumours formed. 17 duplicates were diagnosed in this category, i.e. 52 %. 52 %. In one type of cancer (3 %), brain tumour, and meninges, the latency time was 12 years. Furthermore, I calculated relative risk. The values of relative risk determined were greater than 1 for all types of tumours. The lowest value relative risk was observed in skin cancer, which was 1,939. On the other hand, the highest value of the relative risk was observed in endometrial neoplasm. The value of relative risk reached 48.78. Through this calculation of relative risks I confirmed the hypothesis that after irradiation of breast cancer there is an increasing number of duplicate tumours in comparison with the occurrence of tumours in the general population. Despite the increased values of relative risk, the benefits of radiotherapy in cancer treatment are irreplaceable. When using radio therapy, it is necessary to count with some risk of late complications.
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Investigation of blood cultures
ŠINDELÁŘOVÁ, Radka
Bloodstream infections are among the most serious pathologies with often severe or even fatal course, and therefore the microbiological testing blood cultures is very important. Bloodstream infections caused by various microorganisms - bacteria, viruses, parasites and fungal agents. Each of them in the organism induces a different response and clinical course. The aim of this work was to ascertain the possibility of investigating bloodstream infections, appropriate the technique of treatment of blood cultures in the laboratory of bacteriology in České Budějovice Hospital, Inc. and based on the results determine the percentage of positivity for the months of September and October 2012 and which agents and with what frequency was from the positive blood cultures catched. The theoretical part deals with the explanation of basic concepts that are associated with bloodstream infections and their complications. I also explore the possibilities of investigation in other laboratory branches - biochemistry and hematology which are also very important for the diagnostics of this infections and their importance is especially in speed of obtaining results. The main examination is the clinical microbiology one where culturing agents that cause these diseases, the rapid identification and determination of susceptibility to antimicrobial agents leads to accelerated and targeted therapy. The last section of the theoretical part I dedicated to individual agents that can cause bloodstream infections. The practical part describes the procedure by which blood cultures were processed. At first, I describe the pre-analytical sample testing, which is very important. Here is included the sampling and sample transport to the laboratory. Medical personnel, which take the sampling, should be duly lessoned how to act during the sampling to avoid contamination of the sample, so the patient was not been needlessly prescribed antibiotics. The actual analysis of the examination were performed in blood cultures system the Bact/ALERT 3D bioMerieux, whose principle is based on the colorimetric detection of CO2, arising from the growth of bacteria. If the unit is assessed positively, blood cultures bottle was further processed - inoculated on solid media and microscopic specimen was taken. The research results are displayed using simple statistics in graphs and a chart. From the assignment of the percentage of positivity, that are depicted in the graphs, the result for the months of September and October of 2012 is 17%. Another objective was to determine the isolated agent. These results are in a chart where I put the number of their representation and their relative frequency. The most common were isolated: Escherichia coli, Staphylococcus epidermidis, Staphylococcus hominis, and Staphylococcus aureus. The results, which I reached in this work, are similar to the results in the international literature. The occurrence of Escherichia coli and coagulase-negative staphylococci is presented in the frequency of incidence of agents isolated from the blood cultures in the first place. During the isolation of coagulase-negative staphylococci should be considered their incidence as a possible contamination of the skin flora in case of the taking of blood cultures. During the practical part of the thesis I was closer acquaint with the operation of bacteriological laboratories and methods of its work including techniques of blood cultures processing. These activities are the necessary part of diagnostics of infectious diseases and treatment of the patient.
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Phytoestrogens in the food and their connection to arising of the cancer of breast and of sex organs
Čapková, Petra ; Kudláčková, Zděnka (advisor) ; Hronek, Miloslav (referee)
Estrogens and progestins are female hormones. Thanks to their binding to the estrogen receptor they induce gene expression and thus the response of the organism. They are responsible only not for physiological effects such as bone metabolism, menstrual cycle but they play a role also in the pathogenesis of tumours of the breast and genital organs. The production of endogenous substances, receptors or enzymes which are called tumore markers can be characteristic of tumor growth. Breast and endometrial cancer can be both estrogen dependend and estrogen independent. The increased expression of estrogen or progesterone receptors can be detected in the hormone dependent breast cancer. There are big diferences between the incidence of breast, ovary and endometrial cancer in developed countries (USA, Europe) compared with Japan. This may be because the Japanese population consumes foods with higher content of soybean. Soy is rich in phytoestrogens. They are active plant substances that, among other plants, are found in the red clover, linseed and soybeans. Phytoestrogens can be divided to isoflavones, lignans, coumenstans and stilbens. Their effects are similar to the 17β-estradiol. We can classify them as so-called natural selective estrogen receptor modulators. They have a wide range of effects. They...
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Viruses and cytosketelon of the cell nucleus
Cibulka, Jakub ; Forstová, Jitka (advisor) ; Šťovíček, Vratislav (referee)
The nuclear cytoskeleton (the nucleoskeleton) provides a structural integrity to the nucleus and is involved in number of key processes including transcription, chromatin remodelling and mRNA transport. The nucleoskeleton consists of nuclear lamins, nuclear actin and other proteins. Some viruses, which replicate themselves in the nucleus, use nuclear cytoskeleton in their life-cycle. On the other hand the nucleosketon may also represent a barrier for viral infection. Herpesviruses need nuclear actin for capsid assembly and transport, but they have to desintegrate the nuclear lamina in order to escape the nucleus. Nuclear actin also participates in the morphogenesis and probably nuclear export of baculovirus capsids. Some retroviruses transport their unspliced RNAs from the nucleus using nuclear actin and there is also some evidence of retrovirus-induced nuclear lamina disruption. In this work, I focus on the interactions of above-mentioned viruses with the nuclear cytoskeleton (namely nuclear actin and lamins).
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Imunostimulační a imunoprotektivní vlastnosti makromolekulárních protinádorových léčiv
Říhová, Blanka ; Strohalm, Jiří ; Šírová, Milada ; Etrych, Tomáš ; Mrkvan, Tomáš ; Šubr, Vladimír ; Plocová, Daniela ; Kovář, Marek ; Ulbrich, Karel
Polymeric conjugates of doxorubicin, non-targeted or antibody targeted cure mice from experimental EL4 T cell lymphoma and induce specific, systemic long-lasting anti/tumor resistance
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