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Studies of intercellular interactions in tumours
Jechová, Alžběta ; Smetana, Karel (advisor) ; Skalníková, Helena (referee) ; Masařík, Michal (referee)
Beside tumor cells themselves, tumors consist of many non-malignantly transformed cellular elements and an extracellular matrix. This so-called tumor microenvironment, or stroma, significantly influences the biological properties of the tumor through intercellular interactions. In this thesis I have focused on the study of tumor-associated fibroblasts in squamous cell carcinomas of the head and neck, malignant melanoma and glioblastoma. The data show the presence of cells with mesenchymal characteristics, present even in the glioblastoma stroma, which could potentially have a positive effect on proliferative activity and invasiveness of glioblastoma cells. In malignant melanoma, the presence of keratinocytes should also be considered, as they are the major cells of the epidermis influencing tumor melanocytes. The conditioned medium from UVB irradiated keratinocytes and non-irradiated fibroblasts stimulates the invasion of malignant melanoma cells. Targeting the tumor stroma may be a new direction in oncological therapy, so we have focused on the influence of synthetic polyamine on the formation of myofibroblasts, which are an active part of the population of tumor-associated fibroblasts. The tested polyamine prevents the formation of myofibroblasts but has no effect on those already formed nor on...
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Intercellular interactions in malignant melanoma
Nedvědová, Tereza ; Dvořánková, Barbora (advisor) ; Brábek, Jan (referee)
Melanomas are one of the most aggressive types of tumours, with increasing incidence, high mortality and high potential to metastasize to a variety of diverse locations. The aim of this thesis was to study the tumour as a complex structure consisting not only of tumour cells but also of tumour stroma. Stromal cells play a major role in cancer biology. This is well documented for example in squamous cell epithelium tumours of the head and neck. Similar mechanisms can be expected to occur in melanomas. In the first experiment, we simulated the conditions in vivo during the metastatic process and studied the influence of non-adhesive environment both with and without the influence of stromal fibroblasts. The presented data demonstrates a change of tumour cells' phenotype leading to increased plasticity of the melanoma cells in these conditions. It also indicates the crucial role of stromal fibroblasts in interactions with melanoma cells. Cancer cell lines show variability in their behaviour, which is in accordance with well-known melanoma heterogeneity in clinical practice. The previous experiments in our laboratory indicate that cancer associated fibroblasts are able to influence the phenotype of a tumour cell line and this effect is based on a tumour type-unspecific mechanism. In the second part of...
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New trends in cell and molecular biology of the head and neck cancer
Fík, Zdeněk ; Chovanec, Martin (advisor) ; Komínek, Pavel (referee) ; Ludvíková, Marie (referee)
Head and neck squamous cell carcinomas are still challenging despite progress in the oncological treatment. Study of the molecular biology allows to deeply characterize tumor properties and to predict the prognosis for affected patients. Nowadays there are many drugs clinically tested in the group of targeted therapy medicine Experimental work comprised both in vitro and in situ assays, being performed thanks to the collaboration between a number of departments of the 1st Faculty of Medicine of the Charles University in Prague, Academy of Sciences of the Czech Republic, Institute of Hematology and Blood Transfusion and Faculty of Veterinary Medicine of the Ludwig-Maxmillian University Munich. Galectin-1 is important inductor of the myofibroblasts/cancer associated fibroblasts. These fibroblasts are regarded as negative prognostic markers thanks to their capability of invasive cancer cells induction. On the other hand, Galectin-9 is not present in the carcinoma and in the case of dysplasia, its expression indicate aberrant features together with aberrant expression of keratin 14 and 19. Except from galectins using as prognostic markers, we focused on the galectins as a therapeutics instruments as well. Presented work with mutant variants of galectin-2 proved their effect on both pharmacodynamics and...
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Genetical analysis of head and neck squamous cell carcinomas
Čapková, Markéta ; Plzák, Jan (advisor) ; Smilek, Pavel (referee) ; Čelakovský, Petr (referee)
Head and neck squamous cell carcinoma is the fifth most common cancer worldwide. They are associated with high morbidity and mortality. Despite considerable advances in surgical and oncological treatment over the past two decades, overall treatment outcome has only slightly improved. In my thesis I focused on serum gene expression analysis of head and neck cancer patients, which followed the tissue gene expression analysis in same patients. Further we investigated gene expression analysis in tumour stroma, which is now considered as significant factor in cancer initiation and progression. We revealed several candidate genes, which are involved in signalling pathways connected with cell differentiation and proliferation and are involved in apoptotic pathway (BCl-2, BCl-XL a MAX). As well we detected down-regulation of the main tumour suppressor p 53 protein. In peritumoural tissue we detected overexpression of cytokines typical for embryonal development and ectoderm differentiation - IGF-2 and BMP-4, which significantly influence the phenotype of normal keratinocytes. Further we identified several candidate genes relating with overexpression of Gal-1 in stromal myofibroblasts rich tissue (SPIN1, FUSIP1, TRIM23, SLC25A40, PTPLAD1, MP3K2). HNSCC is a heterogeneous disease despite the presence of...
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Glycobiology of the head and neck cancer
Valach, Jaroslav ; Smetana, Karel (advisor) ; Dřízhal, Ivo (referee) ; Říhová, Blanka (referee)
iii Abstract Glycobiology represents a very progressive subject of cell biology. Protein-saccharide interactions play not only supporting and cell organization role, but they also represent medium for information storage and its decoding. Galectins, group of animal lectins (saccharide-binding proteins), which have selective affinity to ß-galactosides, are multifactorial molecules. They participate in cell-cell and cell-matrix interaction, transmembrane signaling, apoptosis, pre- mRNA splicing and are also present in various types of carcinomas. High expression of galectin-1 has been detected in cancer stroma originated from squamous cell epithelium. In the previous study we established that the fibroblasts - myofibroblasts transition, apart from the known TGF- beta, is also induced by galectin-1. We compared relationship between galectin-1 expression, presence of myofibroblasts and gene expression in tissue samples from patients with head and neck squamous cell carcinoma. Cancer stroma with myofibroblasts was rich in galectin-1 expression in comparison with stroma without myofibroblasts. Moreover, we used microarray analysis (ILLUMINA) to compare the whole genome transcriptome from samples with and without presence of galectin-1. High expression of galectin-1 in tissue samples corresponded with expression...
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Studies of intercellular interactions in tumours
Jechová, Alžběta ; Smetana, Karel (advisor) ; Skalníková, Helena (referee) ; Masařík, Michal (referee)
Beside tumor cells themselves, tumors consist of many non-malignantly transformed cellular elements and an extracellular matrix. This so-called tumor microenvironment, or stroma, significantly influences the biological properties of the tumor through intercellular interactions. In this thesis I have focused on the study of tumor-associated fibroblasts in squamous cell carcinomas of the head and neck, malignant melanoma and glioblastoma. The data show the presence of cells with mesenchymal characteristics, present even in the glioblastoma stroma, which could potentially have a positive effect on proliferative activity and invasiveness of glioblastoma cells. In malignant melanoma, the presence of keratinocytes should also be considered, as they are the major cells of the epidermis influencing tumor melanocytes. The conditioned medium from UVB irradiated keratinocytes and non-irradiated fibroblasts stimulates the invasion of malignant melanoma cells. Targeting the tumor stroma may be a new direction in oncological therapy, so we have focused on the influence of synthetic polyamine on the formation of myofibroblasts, which are an active part of the population of tumor-associated fibroblasts. The tested polyamine prevents the formation of myofibroblasts but has no effect on those already formed nor on...
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New trends in cell and molecular biology of the head and neck cancer
Fík, Zdeněk ; Chovanec, Martin (advisor) ; Komínek, Pavel (referee) ; Ludvíková, Marie (referee)
Head and neck squamous cell carcinomas are still challenging despite progress in the oncological treatment. Study of the molecular biology allows to deeply characterize tumor properties and to predict the prognosis for affected patients. Nowadays there are many drugs clinically tested in the group of targeted therapy medicine Experimental work comprised both in vitro and in situ assays, being performed thanks to the collaboration between a number of departments of the 1st Faculty of Medicine of the Charles University in Prague, Academy of Sciences of the Czech Republic, Institute of Hematology and Blood Transfusion and Faculty of Veterinary Medicine of the Ludwig-Maxmillian University Munich. Galectin-1 is important inductor of the myofibroblasts/cancer associated fibroblasts. These fibroblasts are regarded as negative prognostic markers thanks to their capability of invasive cancer cells induction. On the other hand, Galectin-9 is not present in the carcinoma and in the case of dysplasia, its expression indicate aberrant features together with aberrant expression of keratin 14 and 19. Except from galectins using as prognostic markers, we focused on the galectins as a therapeutics instruments as well. Presented work with mutant variants of galectin-2 proved their effect on both pharmacodynamics and...
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Intercellular interactions in malignant melanoma
Nedvědová, Tereza ; Dvořánková, Barbora (advisor) ; Brábek, Jan (referee)
Melanomas are one of the most aggressive types of tumours, with increasing incidence, high mortality and high potential to metastasize to a variety of diverse locations. The aim of this thesis was to study the tumour as a complex structure consisting not only of tumour cells but also of tumour stroma. Stromal cells play a major role in cancer biology. This is well documented for example in squamous cell epithelium tumours of the head and neck. Similar mechanisms can be expected to occur in melanomas. In the first experiment, we simulated the conditions in vivo during the metastatic process and studied the influence of non-adhesive environment both with and without the influence of stromal fibroblasts. The presented data demonstrates a change of tumour cells' phenotype leading to increased plasticity of the melanoma cells in these conditions. It also indicates the crucial role of stromal fibroblasts in interactions with melanoma cells. Cancer cell lines show variability in their behaviour, which is in accordance with well-known melanoma heterogeneity in clinical practice. The previous experiments in our laboratory indicate that cancer associated fibroblasts are able to influence the phenotype of a tumour cell line and this effect is based on a tumour type-unspecific mechanism. In the second part of...
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Glycobiology of the head and neck cancer
Valach, Jaroslav ; Smetana, Karel (advisor) ; Dřízhal, Ivo (referee) ; Říhová, Blanka (referee)
iii Abstract Glycobiology represents a very progressive subject of cell biology. Protein-saccharide interactions play not only supporting and cell organization role, but they also represent medium for information storage and its decoding. Galectins, group of animal lectins (saccharide-binding proteins), which have selective affinity to ß-galactosides, are multifactorial molecules. They participate in cell-cell and cell-matrix interaction, transmembrane signaling, apoptosis, pre- mRNA splicing and are also present in various types of carcinomas. High expression of galectin-1 has been detected in cancer stroma originated from squamous cell epithelium. In the previous study we established that the fibroblasts - myofibroblasts transition, apart from the known TGF- beta, is also induced by galectin-1. We compared relationship between galectin-1 expression, presence of myofibroblasts and gene expression in tissue samples from patients with head and neck squamous cell carcinoma. Cancer stroma with myofibroblasts was rich in galectin-1 expression in comparison with stroma without myofibroblasts. Moreover, we used microarray analysis (ILLUMINA) to compare the whole genome transcriptome from samples with and without presence of galectin-1. High expression of galectin-1 in tissue samples corresponded with expression...
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Tumor microenvironment: Cancer-associated fibroblasts and their biological function in tumors derived from squamous epithelium
Nedvědová, Tereza ; Kodet, Ondřej (advisor) ; Brábek, Jan (referee)
The incidence of carcinomas originating from squamous cell epithelium increases with population ageing as well as in younger people. The treatment is demanding for both the patient and whole health system. For the successful therapy, there is a need to understand the development and spreading of the tumor to target them specifically. Tumors consist of tumor stroma and malignant cells. Cancer cells are organized in a hierarchic order and the major problem are cancer stem cells. Adult stem cells are defined as cells with the capacity to self-renew as well as the ability to generate differentiated cells within the tumor. Resistance to targeted therapy can improve survival of these cells and is responsible for cancer relapse. Tumor stroma constitutes another important part of tumor. It is composed of non-cancer cells and extracellular matrix and has become recognized as a major factor in cancer growth and metastation. The stroma includes vascular and immune cells and especially cancer associated fibroblasts (CAFs). These cells are not malignant per se, nevertheless their role in supporting cancer growth and survival is important, so they have become an attractive target for treatment. There are several hypotheses made to explain the origin of CAFs. The question is whether the origin of all CAFs in one...
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