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Molecular mechanisms of sensitivity and resistance towards chemotherapeutics in most frequent solid cancers
Čumová, Andrea ; Vodička, Pavel (advisor) ; Černá, Marie (referee) ; Hlaváč, Viktor (referee)
Despite the great effort, the main obstacle to cancer therapy represents low response towards common chemotherapeutics and/or resistance. Chemoresistance causes cancer relapse and formation of metastases, dramatically challenging the prognosis of patients. It is estimated, that about 90% of cancer mortality can be directly or indirectly attributed to chemoresistance. There are several intrinsic or acquired cellular mechanisms of tumor chemoresistance, with DNA repair being one of the key culprits affecting the response towards chemotherapeutics in cancer cells. This is based on the fundamental principle of their action, as the majority of chemotherapeutics are designed to increase DNA damage and to suppress DNA repair or DNA damage response, ultimately triggering the death of malignant cells. Consequently, understanding the complex mechanisms of DNA repair and its regulation is essential for more targeted and effective treatment of cancer patients. In this dissertation Thesis, we attempted to elucidate some of the regulatory mechanisms of DNA repair and their effects on response to common chemotherapeutics. We confirmed that single nucleotide polymorphisms in microRNA binding sites of DNA repair genes may influence the patient's survival and response to cancer therapy. We investigated the role of...
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Characterization of germline alterations affecting genes influencing development and prognosis of specific adult cancers
Jelínková, Sandra ; Kleibl, Zdeněk (advisor) ; Hlaváč, Viktor (referee) ; Hájková, Nikola (referee)
In my dissertation, I studied the genetic predisposition of selected types of cancer that have not been systematically studied in the Czech Republic. We used next-generation panel sequencing to identify germline pathogenic variants. Analysis of 1333 patients with ovarian cancer, 527 patients with endometrial cancer, and 334 patients with hepatocellular carcinoma included sequencing using the CZECANCA panel. A specific CZMELAC panel was prepared for the analysis of 264 melanoma patients. We focused on the identification of pathogenic variants in known predisposition genes. We also evaluated candidate genes and phenotypic characteristics in carriers of pathogenic variants. Analysis of high-risk melanoma patients revealed pathogenic variants in melanoma associated genes in 9/264 (3.4%) patients, and an additional 22 (8.3%) patients carried a pathogenic variant in one of the other predisposition genes. The odds of carrying a pathogenic variant were increased in probands with multiple melanomas and in the presence of melanoma in relatives. The incidence of germline pathogenic variants was highest in ovarian cancer, where pathogenic variants were found in 427/1332 (32.0%) patients, with a predominance of mutations in BRCA1, BRCA2, followed by alterations in other ovarian predisposition genes. Breast and...
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High grade serous ovarian carcinoma: molecular background and platinum-based chemotherapy challenges
Ivančinová, Jana ; Heneberg, Petr (advisor) ; Brábek, Jan (referee)
Ovarian carcinoma (O.C.) represent a group of various disease entities derived from ovaries. The most common malignant gynaecological cancer is high-grade serous ovarian carcinoma (HGSOC). HGSOC is associated with a high mortality rate due to its aggressive behaviour and insufficient early-stage detection. The survival rate has not been significantly improved since 1970s. The most effective treatment of HGSOC patients is by cytoreductive surgery (for early stages I/II) and followed by platinum-based chemotherapy (HGSOC presented in advanced stage III/IV) combined with taxane or potentially with PARP inhibitors (for BRCA1/2 mutation carriers). Multiple factors affect the patient's outcome and prognosis. Chemoresistance, molecular mutational patterns, stage at presentation of HGSOC are one of the clinical challenges contributing to common relapses even though patients often initially respond well to the HGSOC chemotherapy. This thesis overviews the fundamental biology of HGSOC, the major obstacles in clinical management and its improvements by implementing of multitherapy approaches. Key words: CA-125; platinum−based chemotherapy treatment; homologous recombination deficiency; ovarian carcinoma; resistance; Tp53; mortality; survival rate
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Analysis of hereditary genetic variants predisposing to the development of familial forms of ovarian cancer.
Lhotová, Klára ; Soukupová, Jana (advisor) ; Mohelníková Duchoňová, Beatrice (referee) ; Weinberger, Vít (referee)
Ovarian cancer (OC) is the deadliest gynecologic malignancy with a substantial proportion of hereditary cases and a frequent association with breast cancer (BC). Genetic testing facilitates preventive management for carriers of mutations in OC-susceptibility genes. However, the prevalence of germline mutations varies among populations and many rarely mutated OC predisposition genes remain to be identified. We analyzed 219 genes in 1333 Czech OC patients and 2278 population-matched controls (PMC) using next-generation sequencing. Altogether, 427/1333 (32%) patients and 58 /2278 (2,5%) PMC carried pathogenic mutations in 18 known/anticipated OC predisposition genes. Mutations in BRCA1, BRCA2, RAD51C, RAD51D, BARD1 and mismatch repair genes conferred a high OC risk (with OR>5). Mutations in BRIP1 and NBN were associated with moderate risk (both OR ≥2 - <5). BRCA1/2 mutations dominated in almost all clinicopathological subgroups including sporadic borderline tumors of ovary (BTO). Analysis of remaining 201 genes revealed somatic mosaics in PPM1D and germline mutations in SHPRH and NAT1 associating with a high/moderate OC risk significantly; however, further studies are warranted to delineate their contribution to OC development in other populations. Results of this study demonstrate the high proportion...
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Nursing care of the patient with ovarian cancer
Hladíková, Ivana ; Holubová, Jana (advisor) ; Tikovský, Karel (referee)
The objective of this work is elaboration of case study, nursing care of the patient with ovarian cancer, 63 years old patient has been hospitalized on the clinic of gynecology and obstetric because of gynecology operation. The theoretical part deals with general introduction to the anatomy and physiology of female genital organs, here are shown some risk factors for ovarian cancer, symptoms and current possibilities of diagnosis and treatment of ovarian cancer. Nursing part contains description of nursing care of the patient in early post operating time. The nursing care has been performed by the theory of nursing process. Evaluation has been performed by the model of Marjory Gordon. Meaningful part of this work is a chapter about the educations. The work is finished by lists of references, abbreviations and completed by several supplements. Powered by TCPDF (www.tcpdf.org)
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New molecular biomarkers and therapeuticak targets in solid tumors
Voleská, Iveta ; Václavíková, Radka (advisor) ; Moulisová, Vladimíra (referee)
Breast and ovarian cancers are the most serious cancers among women. Relatively high mortality at advanced stages of the disease is often associated with the development of resistance to the cytotoxic agents. Chemoresistance usually develops on the base of different adaptive mechanisms that significantly decrease therapy efficiency. Currently TRIP6, ABCC3 and CPS1 enzyme has been identified based on high-capacity expression profile monitoring in tumor cell and tissue profiles as one such candidate playing a role in taxane resistance. The main goal of this thesis was to clarify the role or possible association of the ABCC3, CPS1 and TRIP6 genes with the development of tumor cell resistance to taxanes in models of sensitive and paclitaxel-resistant ovarian cancer cells and in the cohorts of patients with ovarian and breast cancer. The in vitro part compares the efficacy of paclitaxel and taxane derivatives in the sensitive and resistant ovarian cancer cell lines and clarifies the association between the different structure of taxane derivatives and the change in CPS1 expression after their application. The study in patient's cohorts with ovarian cancer reveals a relationship between higher levels of the CPS1 gene and shorter progression-free survival. The achieved results may serve as a base for data...
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The role of DNA repair pathways in ovarian cancer therapy response
Vallušová, Dominika ; Opattová, Alena (advisor) ; Rössner, Pavel (referee)
Ovarian cancer is serious and one of the most common gynecologic cancers. Carboplatin is the therapeutic agent of the first choice in the ovarian cancer therapy. However, after the primary therapeutic response to carboplatin, the relapse of the disease may occur with developed resistance to carboplatin. Chemoresistance and insufficient therapy response are considered to be the reason of the high mortality rate of ovarian cancer. The DNA damage response pathways play an important role in the therapeutic response and chemoresistance development. Restoration of homologous recombination function in cancers is the key mechanism of resistance development to platinum agents. Based on this knowledge, we formed our hypothesis, that the inhibition of homologous recombination could increase the sensibility to carboplatin. The main goal of this thesis was to define the role of double-strand breaks repair in response to chemotherapy of ovarian cancer. Protein MRE11 is part of the MRN complex, that participates in double-strand breaks repair. Using mirin as a pharmaceutic inhibitor of MRE11 we were aiming to determine the impact of homologous recombination on the effect of carboplatin and its role in resistant development to carboplatin. In the practical part of the thesis, we described the association between...
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Biomarkers of epithelial ovarian tumors and of the endometrium
Presl, Jiří ; Novotný, Zdeněk (advisor) ; Špaček, Jiří (referee) ; Fingerová, Helena (referee)
Structured abstract Study objectives: Ovarian carcinoma 1/ comparison of sensitivities among monitored markers CA 125, HE4, CA 19-9, CEA, TK, TPS, MonoTotal 2/ comparison of false positivity of markers CA 125 and HE4 3/ use of CA 125, HE4 and ROMA index in the diagnostics of ovarian carcinoma 4/ use of CA 125 and HE4 in the follow-up of ovarian cancer Endometrial carcinoma 1/ feasibility of use of biomarkers CA125 and HE4 in patients with endometrial cancer in pre- operative management Study design: Retrospective data analysis Settings: Department of Obstetrics and Gynecology, Medical Faculty and Teaching Hospital in Pilsen Patients and Methods: Ovarian cancer 1/ Sensitivity of markers CA 125, HE4, CA 19-9, CEA, TK, TPS, and MonoTotal was assessed in 266 patients - 19 with ovarian cancer and 247 with benign disorders. 2/ False positivity of markers CA125 and HE4 was evaluated in a total of 390 patients with benign diagnoses - 60 women with endometriosis, 70 pregnant patients, 67 patients with ascites, 60 with pleural effusion, 25 with cardiac failure , 80 with renal insufficiency and 28 with hepatic failure. 3/ As a part of this objective we evaluated 552 patients with abnormal pelvic abnormality - 30 women had a histologically confirmed malignant ovarian tumor. Other 522 women had a benign condition. The...
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Biological behavior of ovarian carcinoma and its relation to therapy
Bartáková, Alena ; Bouda, Jiří (advisor) ; Špaček, Jiří (referee) ; Svoboda, Tomáš (referee)
Structured abstract Hypothesis Cancer stem cells (CSCs) are subpopulations of cells which could contribute to tumor growth, metastasis formation and chemoresistance. CSCs can be detected by surface markers assessed by immunohistochemistry methods. A typical surface marker for CSCs is CD44 (standard form). We assumed, that CD44(s) could serve as a prognostic factor and marker of chemoresistance in patients with epithelial ovarian cancer. The aim of study 1. To recruit group of patients with histologically verified epithelial ovarian carcinoma. 2. To evaluate prognostic significance of known prognostic factors in our series of patients. 3. To assess the expression of CD44 in specimens of primary tumors and specimens of implantation metastasis using immnunohistochemistry and analyze their correlation. 4. To evaluate the expression of CD44 in relation to known prognostic factors. To analyze the significance of CD44 expression evaluation for overall survival, disease-free interval and chemoresistance. To find CD44 positivity cut-off by using statistical methods Materials and Methods A retrospective study was performed on 87 patients with histologically verified EOC. All patients were tested for primary tumor specimens, 48 of them were tested with regard to both specimens of primary tumor and implantation...
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Proteomics as a tool for understanding molecular mechanisms of human diseases
Pospíšilová, Jana
Proteomics is a set of analytical methods which enable qualitative and quantitative characterization of the proteome. Expression proteomics quantitatively compares proteomes of cells, tissues, body fluids or other biological materials to find differencies in protein expression and, based on these differencies, to describe the biological processes occuring in investigated organisms. An initial material for expression proteomic studies are complex mixtures containing thousands of proteins, which are analyzed using separation (electrophoretic and chromatographic) methods, and identified, possibly quantified using mass spectrometry. The aim of this Thesis is to demonstrate the application of the tools of expression proteomics in solving diverse challenges in biomedicine. We employed various proteomic approaches and tools for studying molecular mechanisms of human diseases using pacient biological samples, or a model organism and a cell culture. We were conducting three different research projects, namely: A quest for potencial molecular targets for selective elimination of TRAIL-resistant mantle cell lymphoma cells; Investigation of molecular mechanisms of heart failure using a rat model of the disease induced by volume overload; and Searching for diagnostically usable serum biomarkers of ovarian...
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