In humans, multi enzymatic processes are involved in maintaining DNA stability and cellular homeostasis. Cells undergo several episodes to survive and protect itself in daily basis. Accumulation of DNA errors and breaks are repaired by dynamic machinery, such as mismatch repair (MMR), replication-related process. In presented diploma thesis, we report the studied MMR pathway and its involvement in malignancy of epithelial ovarian cancer (EOC). Our working hypothesis postulated that core genes of MMR, such as MLH1 and MSH2 are down-regulated in malignant cells. Cells therefore become incapable to repair accumulating DNA damage, undergo apoptosis or most likely uncontrolled proliferation. Above mentioned genes may also be silenced in cancer patients at transcription, translation or epigenetic levels. Our aims were to clarify and to investigate the importance of MMR based on mRNA transcription, protein stability and promoter hypermethylation on a set of major MMR genes, particularly MLH1, MSH2, PMS1, MLH3, MSH6, MSH3, and PMS2. In our study, we analysed samples from 63 epithelial ovarian cancer patients and 12 non-malignant reference tissues using RT-qPCR, MS-HRM, and Western Blotting methods. Consequently, our results show down-regulation of all MMR genes except for MSH2 (up-regulated) in tumor...

This work will first introduce the problems related to the colorectal cancer - its epidemiology and screening possibilities. Next the main topic is addressed - i.e. to ascertain the influence of national screening programmes for colorectal cancer on really observed data of lethality and incidence of this disease. Group of so-called APC models was selected as a useful tool for this purpose. Applying these methods on data of The National Oncological Registry of the Czech Republic for the period between 1980 till 2009 this work aims to prove expected reducing effect of area-wide screening programme on incidence and lethality related to colorectal cancer. Using the AP model and data of previous period before the screening introduction (i.e. 1980-1999) the values of incidence and lethality were predicted for the period in question (i.e. 2000-2009). Mere comparison of this predicted values with really observed data showed that real lethality and incidence was significantly lower in both sexes as compared to the model without the screening intervention. Difference between predicted and real data corroborates positive influence of colorectal cancer screening.

The Breast cancer gene 1 (BRCA1) codes for nuclear phosphoprotein with a key function in the regulation of DNA damage response. The BRCA1 protein contributes to the formation and regulation of protein supercomplexes that participates on the DNA double-strand break repair. These protein supercomplexes are formed by the protein-protein interactions between highly conservative protein motives in BRCA1 and its binding partners. Except to the wild type form of BRCA1 mRNA containing entire set of 22 exons coding for the 220 kD protein, numerous alternative splicing variants (ASVs) BRCA1 mRNA has been described. These ASVs code for BRCA1 isoforms lacking several critical functional domains. It has been proposed, that formation of BRCA1's ASVs represent a tool for regulation of BRCA1 function. Only poorly has been characterized a complex catalogue of in various human tissues and their expression. This study aims to address these questions. We optimized the identification of BRCA1's ASVs including those covering the entire transcripts of the wt BRCA1 mRNA with length exceeding 5.5 kb. In further analysis, we characterized 13 BRCA1's ASVs in RNA samples isolated from peripheral blood mononuclear cells (PBMNC) obtained from patients with breast cancer (BC) and control subjects. The majority of the identified...

The study is designed as a prospective clinical trial. Patients with histologically proven head and neck cancer treated by curative radiotherapy were included. The aim of this study was to investigate the relationship between pretreatment or posttreatment nutritional status and overall surival or locoregional / distant control. Pretreatment and posttreatment nutritional status was evaluated by body weight, body mass index, total serum protein, albumin, prealbumin, transferin and cholinesterase. Univariete and multivariete regression analyses were applied for prognostic factors associated with survival or tumor control. In this study we demonstrated, that poorer nutritional status prior curative radiotherapy, has a negative impact on subsequent control of cancer. The most sensitive parameter was serum cholinesterase. Serum cholinesterase  108 kat/l was the independent negative prognostic factor for both locoregional and distant tumor control. Results of this study indicate the need for intensive nutritional support before starting of curative treatment.

The thesis The analysis of genetic factors of breast cancer by NGS deals with the current serious problematics of breast cancer from the perspective of genetic predisposition. Breast cancer is one of the most common tumors in women. Every year more than 7000 women are diagnosed with this disease and the mortality rate in the Czech Republic is nearly 2000 cases. Of the total number of patients diagnosed with breast cancer, approximately ten percent of patients have congenital mutations in one of the predisposing genes that cause a significantly increased risk of developing a cancer. More than half of these mutations occur in germline mutations of the BRCA1 or BRCA2 genes, others include a number of other genes, eg tp53, CDH1, PTEN, STK11, ATM, PALB2, CHEK2.Early diagnosis and identification of persons with increased risk of developing breast cancer is of key importance for their inclusion in preventive programs. Therefore, the thesis aims to testing genes that can cause a breast cancer. In the thesis, 219 known and candidate predisposition genes were analyzed in a group of 263 non-selected breast cancer patients using a targeted panel NGS, the Illumina platform. Selected identified suspect variants were further confirmed by Sanger sequencing. The aim of this work was also a mutational analysis of...

The master's thesis Women after breast cancer describes the influence of breast cancer on some aspects of the psychosocial life of affected women. In the theoretical part, the author describes the breast cancer, its causes, incidence, presents classification of tumors and risk factors, introduces strategies for prevention and makes the reader aware of symptoms and the quality of life of sufferers. Furthermore, the author analyzes contemporary therapies for the treatment of breast cancer. The empirical part of the master's thesis includes four interviews that serve as the basis for analysis and interpretation of the research. The goal of this thesis is to understand what influence breast cancer has on some of the psychosocial aspects of life of women that suffered from it. The author also investigates what obstacles the breast cancer causes within family life, its influence on work, the psychological state of the victims and what factors created the most difficulties during patients' treatment. The author chose the method of qualitative research, and the techniques of semi-structured interview, analysis of medical documentation and self-observation. KEYWORDS Breast cancer, quality of life, psychosocial aspects of tumor

The cancer treatment is, thanks to new technologies, very expensive, nowadays. According to demographic data and analysis the Czech population is aging, and it is highly probable that these costs will rise even more. Therefore it is necessary to look through pharmacoeconomic analyzes to find optimal solutions of treatment. The goal of this thesis is to clarify the concept of pharmacoeconomics, cancer and breast cancer. Through the use of demographic data the aim is to assess the status of cancer patients in the future, determine the amount of expenditures for the treatment of breast cancer I have used a model patient, suffering this disease, determine the amount and cost of the conventional and biological method of treatment.

In current days, examination of circulating tumor DNA (ctDNA) finds new use across different cancers. It is directed at tumor-derived short fragments of DNA present in peripheral blood of patiens (mainly in advanced stages). Due to its minimal invasivity, almost 100 % specificity and relatively high sensitivity in stage IV patients, this approch found its main potential clinical utility especially in early detection of disease relapse or progression after tumor resection (i.e. post-operative follow-up), prediction and monitoring of therapy response and estimation of prognosis. As a result of minute levels of ctDNA on a high background of other non-tumor DNA fragments present in plasma, a suitable method exhibiting highest sensitivity is the key for proper detection of this marker. The approach is predominantly based on initial identification of a mutation in tumor tissue and its subsequent detection in plasma. The present work is aimed at optimization of ctDNA isolation and method of its detection based on PCR amplification followed by heteroduplex analysis by denaturing capillary electrophoresis (DCE) to achieve highest sensitivity for detection of mutated fraction in plasma sample. I have applied the optimized protocol to examine ctDNA in three types of cancers, namely colorectal cancer (122...

Colorectal cancer is one of the most common type of malignity. Despite of the existence of numerous studies focused on this carcinoma, there are still many unknown features regarding its diagnosis, treatment or prognosis. In the thesis we focused on the identification of novel prognostics markers that could be useful for the stratification of patients based on the disease outcomes. In the first study we immunohistochemically assessed expression of two proteins associated with cancer stem cells in the samples of primary colorectal cancer and matched liver metastasis. Goal of the study was to evaluate relation among expression of CD44 and CD133 and overall survival and disease free interval in our set of patients. We observed that increased ratio of CD133 positive compared to CD133 negative tumor glands resulted in longer disease free interval, finding which is opposite to the general view on the CD133 role in the cancer development. Our hypothesis is that we analyzed confined group of patients and followed a bit different goal, where we measured ratio between positive and negative glands in the view-field and not the intensity of staining as the previous studies did. Our second study was focused on the transcriptional analysis of the selected set of twelve genes using frozen samples from colorectal...

Predictive and prognostic factors in gastric cancer Šmíd D. Surgical clinic of University Hospital in Pilsen and Faculty of Medicine in Pilsen, Charles University in Prague. Introduction: Gastric cancer is one of malignant diseases which have the worst prognosis. Unfortunately, there are most patients with advanced-stage disease who have to be treated in a palliative way. Patients suffered from the same type of tumor, being at the same stage of disease and treated with the same chemotherapy have various rates of survival, which can be caused by diverse expression of selected genes impacting on the mechanism of cytostatic effects. The determination of these genes or microRNAs which regulate these genes could be used as a predictive factor for prediction of effects of administered chemotherapy. The determination of some microRNAs, or in the combination with suitable plasmatic factors, could be used as a prognostic factor for patients with gastric cancer. It is also possible to use this combination for early diagnosis of cancerogenesis Object: The aim is to verify the possibility to use expression of selected genes and some microRNAs in tumor tissue as a prognostic factor or a predictor for therapeutic effects of chemotherapy in patients with gastric cancer. Methodology: We retrospectively evaluated the group...