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Role of fibroblasts in wound healing and cancer
Mateu Sanz, Rosana ; Smetana, Karel (advisor) ; Masařík, Michal (referee) ; Mokrý, Jaroslav (referee)
Fibroblasts are stromal cells ubiquitously present in the human body. They often appear in a quiescent state and can become activated in response to tissue remodeling signals. Activated fibroblasts acquire biosynthetic, pro-inflammatory and contractile properties, key functions for wound healing. In addition, the presence of permanently activated fibroblasts is one of the hallmarks of cancer. The purpose of this work is to investigate the differences between newborn and adult fibroblasts and keratinocytes in their implication in scarless wound healing, the origin of cancer associated fibroblasts (CAF)s and the influence of fibroblasts in melanoma invasion. Evidence suggests that wounds heal almost without scar in newborns. To understand the mechanisms that contribute to scarless wound healing we focused on the differences between newborn and adult fibroblasts and keratinocytes, which are cells present in human skin and participating in wound healing process. A comparison of the expression profile between newborn and adult fibroblasts showed differentially regulated genes related to the acute phase of the inflammatory response and ECM organization, traits involved in wound healing. We also found that newborn fibroblast showed higher differentiation potential, exhibited markers of pluripotency and...
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Tumor microenvironment modulation and the impact on cancer immunotherapy
Musil, Jan
Modulation of the tumor microenvironment represents a possible way to inhibit cancer growth and enhance anti-cancer immune responses. In the presented work we employ two strategies for tumor microenvironment modulation. Firstly, we have constructed rVACV co-expressing the tumor suppressor gene insulin-like growth factor-binding protein-3 (IGFBP- 3) and the fusion gene encoding the immunogen SigE7LAMP. The expression of IGFBP-3 was regulated either by the early vaccinia virus H5 promoter or by the synthetic early/late (E/L) promoter. We have shown that expression of IGFBP-3 regulated by the H5 promoter yielded higher amounts of IGFBP-3 protein when compared with the E/L promoter. Immunization with P13-SigE7LAMP-H5-IGFBP-3 was more effective in inhibiting the growth of TC-1 tumors in mice and elicited a higher T-cell response against VACV-encoded antigens than the control virus P13-SigE7LAMP-TK- . We found that high-level production of IGFBP-3 enhanced virus replication both in vitro and in vivo, resulting in profound antigen stimulation. Production of IGFBP-3 was associated with a higher adsorption rate of P13-SigE7LAMP-H5-IGFBP-3 to CV-1 cells when compared with P13-SigE7LAMP-TK- . We have identified two structural differences between the IMVs of the IGFBP-3 expressing virus P13-SigE7LAMP-H5-IGFBP-3...
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Detection and characterization of macrophages in the tumors of viral and non-viral etiology
Dalewská, Natálie ; Tachezy, Ruth (advisor) ; Krulová, Magdaléna (referee)
Head and neck cancers are etiologically associated with smoking and alcohol consumption. Part of these tumors is induced by HPV and their incidence is increasing in the last decade. Patients with virally induced tumors have better prognosis even though they are usually diagnosed with tumors in advanced stage. One of the possible explanations may be better stimulation of the immune system by viral antigens. Macrophages are cells of the innate immune system which belong to professional phagocytes. They are called TAM upon infiltration to the tumor where they represent heterogeneous group of cells. Two main phenotypes are antitumor M1 and protumor M2 macrophages. TAMs are a major component of tumor microenvironment of many types of tumors, one of them are also head and neck cancers. In my thesis I focused on the immunohistochemical detection of M1 and M2 macrophages in the head and neck tumors of viral and non-viral etiology and at the same time RT-qPCR analyses of gene expression of macrophage-associated and/or immunosuppressive genes IDO1, ARG1, CD163, NOS2 a PTGS2 was performed. My data showed that HPV- negative tumors had higher number of M2 macrophages with typical markers CD163, ARG1 and PTGS2. It is known that patients with these tumors have worse prognosis of the disease. Due to high...
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Immune response and tumor microenvironment in the treatment with polymer cytotoxic drugs
Malátová, Iva ; Šírová, Milada (advisor) ; Stollinová Šromová, Lucie (referee)
Chemotherapy is still one of the most widely used anticancer therapies. It is mostly about inhibiting the proliferation of rapidly dividing cells, so it is not selective for tumor cells. As a result, many undesirable side effects are associated with chemotherapy. The disadvantageous properties of chemotherapeutics can be largely eliminated by using conjugates of polymers with low molecular weight drugs. An example of such a conjugate is a doxorubicin-linked HPMA polymer. In addition to the properties obtained by polymer binding, such as achieving solubility in aqueous solutions, reducing systemic toxicity, increasing the maximum tolerated dose, or passive targeting by the EPR effect, the fact that doxorubicin induces immunogenic cell death is used in therapy with this drug. It has already been shown that after complete cure of the experimental mice with polymeric conjugates of HPMA with doxorubicin, some mice develop long-term resistance to re-inoculation with a lethal dose of tumor cells. Resistance is specific to the particular line of tumor cells from which the mouse was cured, and CD8+ cytotoxic T cells and IFNγ play an important role. In this work, we monitored changes in the proportion of immune populations and their activation markers after treatment with HPMA-based polymers with doxorubicin...
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Immunoscore in 3D tissue
Novák, Jaromír ; Drbal, Karel (advisor) ; Procházka, Jan (referee)
Solid tumors are complex structures comprising besides the cancer cells vasculature, extracellular matrix (ECM), soluble molecules and a plethora of various other cell types. These components form a so-called tumour microenvironment. From the numerous cell types that are part of tumor microenvironment, tumor infiltrating lymphocytes (TILs) play a major role in patient prognosis. Their presence is also of major importance with regard to new biological therapies based on immune checkpoint inhibitors. Crucial role of TILs is also reflected by the new approaches in cancer diagnostics namely by Immunoscore method (currently used in clinical settings). Immunoscore is based on localization and quantification of CD3+ and CD8+ TILs in thin histological sections of tumor tissue. The question remains to which extent the information obtained from 2D slices reflects the situation in tumor microenvironment considering its spatial heterogeneity. The development of new methodological approaches allowing evaluation of histological information in 3D is the key to answer this question. The theoretical part of this work first describes the heterogeneity of the tumor microenvironment and the role of immune cells within it. Then, the role of spatial heterogeneity and its possible influence on the histopathological...
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Intercellular interactions in skin tumors.
Kučera, Jan ; Smetana, Karel (advisor) ; Masařík, Michal (referee) ; Kovář, Marek (referee)
The dissertation is focused on the study of intercellular interactions in skin tumors. It is based on 5 original publications that cover several topics. We studied the origin of tumor-associated fibroblasts concerning the primary tumor population. We demonstrated using a mouse model that tumor-associated fibroblasts are produced from the host organism and thus did not arise from transformation directly from tumor cells. We also investigated the relationship between tumor-associated fibroblasts and keratinocytes. We have shown that tumor-associated melanoma fibroblasts affect keratinocytes which, under their influence, acquire the features typically observed in migrating cells and cells undergoing epithelial-mesenchymal transition. We studied the interactions between healthy fibroblasts and tumor cells. We have demonstrated that fibroblasts acquired from healthy skin from a patient suffering from melanoma are significantly different from control fibroblasts of healthy donors in the expression profile. Changes in distal fibroblasts support the view of melanoma as a systemic disease. We have further demonstrated that melanoma-associated fibroblasts do not carry a BRAF mutation, in contrast to BRAF positivity of melanoma cells. And therefore, they did not arise from the transition from melanoma. The...
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Dipeptidyl peptidase-IV and Fibroblast activation protein in gliomagenesis.
Trylčová, Jana ; Šedo, Aleksi (advisor) ; Mandys, Václav (referee) ; Mareš, Vladislav (referee)
"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 (DPP-IV) cleaves out X-Pro dipeptides from the N-terminus of peptides. Other molecules carrying similar enzyme activity, such as Fibroblast activation protein (FAP), DPP-II, DPP8 and DPP9 or even DPP-IV structure-like but hydrolytically inactive molecules (DPP6 and DPP10) also belong to this group. Recent knowledge suggest a substantial role of DASH in cancer pathogenesis. The aim of this study is a preparation of a biological model and its use for understanding the mechanisms of interaction(s) between transformed glial cells and stroma in the processes of origin and development of tumors derived from neuroectoderm. Stable transfected human glioblastoma cell lines with inducible gene expression of DPP-IV, Fibroblast activation protein and their enzymatically inactive mutated forms, were prepared within the project. Prepared cell lines are used as a tool for studying not only the "autocrine" importance of DPP-IV and FAP for the expressing cells in in-vitro, but also for their potential "paracrine" effect(s) within the tumor microenvironment after homotopic implantation into the...
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Experimental verification of in silico predicted protein binder to FOXO4 transcription factor and transcriptome analysis of bladder cancer
Tauš, Petr ; Drbal, Karel (advisor) ; Převorovský, Martin (referee)
This diploma thesis includes an experimental and a bioinformatic part. The two parts are linked together through the subject of transcription factors of 'forkhead box O' (FOXO) family. FOXO transcription factors have a key role in many cellular processes including cell cycle regulation, apoptosis and metabolism. For a long time, they have been considered strictly as the tumor-suppressors yet a growing number of evidence is pointing out to their pro-tumorigenic role. In consequence FOXO transcription factors are studied intensively as potential therapeutic targets in cancer. In the past decade, in silico prediction of protein-protein interactions has become popular in basic research as well as in drug development. Nonetheless, the predicted structures are still far from fitting to the expected behavior of the respective biomolecules. In the experimental part of this thesis, I verified the interaction of four in silico predicted protein binders based on naturally occurring PDZ domain with FOXO4 using microscale thermophoresis. Non-invasive bladder tumors represent a heterogeneous disease where reliable prediction of tumor aggressiveness is still lacking despite an intensive research. In the bioinformatic part of this thesis, I described the cellular composition of the tumor microenvironment and demonstrated...
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