O melanoma é a forma mais letal entre os cânceres de pele. Essa neoplasia freqüentemente apresenta-se resistente a abordagens terapêuticas. A angiogênese associada ao tumor representa um crítico passo da tumorigênese, resultado da ação de diferentes citocinas e fatores de crescimento como VEGF produzidos no microambiente tumoral. As galectinas extracelulares participam de múltiplos processos biológicos incluindo angiogênese tumoral e metástases, sua interação com as células presentes no microambiente tumoral pode ocorrer via receptores toll-like sugerindo seu envolvimento nos processos pro-inflamatórios e na secreção de citocinas. Recentemente mostramos que a ausência de gal-3 no estroma e parênquima tumoral diminui a angiogênese por interferir na resposta de macrófagos via VEGF e/ou TGFbeta1. Entretanto, o envolvimento de galectinas extracelulares na angiogênese e na modulação do sistema imune no microambiente tumoral ainda não está esclarecido. Assim, este estudo visa buscar respostas ao envolvimento das galectinas no crescimento tumoral e angiogênese contribuindo ao combate do melanoma maligno. Nossos resultados mostram a participação das galectinas 1 e 3 no crescimento tumoral e seu envolvimento com macrófagos via receptores toll-like, além de coordenarem a modulação do perfil de polarização de macrófagos derivados da medula óssea de camundongos wild-type. Dessa forma, podemos inferir que essas galectinas agem como coordenadoras de mudança de perfil dos macrófagos, uma vez que inibidas extracelularmente promovem uma diminuição do crescimento tumoral em camundongos wild-type, inoculados com células de melanoma murino e uma manutenção do perfil de macrófagos M1 in vitro. Assim, concluimos que as galectinas 1 e 3 extracelulares são importantes para o crescimento tumoral de melanomas murinos pois promovem o crescimento tumoral e são coordenadoras da mudança do perfil de macrófagos / Melanoma is the most aggressive form of skin cancer. This tumor often presents itself resistant to therapeutic approaches. The tumor-associated angiogenesis is a critical step in tumorigenesis and the result of the action of several cytokines and growth factors such as VEGF produced in the tumor microenvironment. The extracellular galectins participate in multiple biological processes including tumor angiogenesis and metastasis, their interaction with cells present in the tumor microenvironment may occur via toll-like receptors suggesting their involvement in pro-inflammatory processes and the secretion of cytokines. We have recently shown that the absence of Gal-3 the stroma and tumor parenchyma decreases angiogenesis by interfering with the macrophage response by VEGF and / or TGFbeta1. However, the involvement of extracellular galectins on angiogenesis modulation of the immune system in the tumor microenvironment is not yet clear. This study aims is to find answers to the involvement of galectins on tumor growth and angiogenesis contributing to the study of the malignant melanoma. Our results demonstrate the involvement of galectin 1 and 3 on tumor growth and its involvement in macrophage by toll-like receptors pathway, and coordinating the modulation of the polarization profile in wild-type mice bone marrow derived macrophages. Therefore, we show these galectins act as coordinators of macrophages profile change, since inhibited extracellularly promote a reduction in tumor growth in wild-type mice inoculated with murine melanoma cells and macrophages M1 maintenance of profile in vitro. Thus, we conclude that galectins 1 and 3 extracellular are important for tumor growth of murine melanomas because they promote tumor growth and are coordinators of change macrophages profile

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...

This thesis is focused on the epithelial mesenchymal interactions in tumors derived from squamous epithelium including tumors arising from minor cell population (melanocytes). This study is also reflecting aspects of epithelial glycobiology resp. the study of endogenous lectins, the galectins, in head and neck squamous carcinomas. Galectins represent, in the current concepts of cell and tumor biology molecules with a remarkable potential. Galectins participate, besides in regulation of pre- and postnatal homeostasis in normal tissues, also in many pathological processes such as autoimmune reactions or malignancies. In this thesis, we demonstrated the presence of galectin-1 and -2 and their glycoligands in interphasic and mitotic nuclei, which may contribute to regulation of the cell cycle. Furthermore, we demonstrated galectin-9 as a sensitive marker of transformation normal to the dysplastic squamous epithelium in head and neck. The epithelial mesenchymal interactions represent mechanisms, which are responsible for dynamic maintenance of the homeostasis of the organism during prenatal development, postnatal growth and during cyclic renewal of certain tissues. These interactions also participate in wound healing. On the other hand they play a crucial role in the process of tumor transformation,...

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...

This thesis is focused on the epithelial mesenchymal interactions in tumors derived from squamous epithelium including tumors arising from minor cell population (melanocytes). This study is also reflecting aspects of epithelial glycobiology resp. the study of endogenous lectins, the galectins, in head and neck squamous carcinomas. Galectins represent, in the current concepts of cell and tumor biology molecules with a remarkable potential. Galectins participate, besides in regulation of pre- and postnatal homeostasis in normal tissues, also in many pathological processes such as autoimmune reactions or malignancies. In this thesis, we demonstrated the presence of galectin-1 and -2 and their glycoligands in interphasic and mitotic nuclei, which may contribute to regulation of the cell cycle. Furthermore, we demonstrated galectin-9 as a sensitive marker of transformation normal to the dysplastic squamous epithelium in head and neck. The epithelial mesenchymal interactions represent mechanisms, which are responsible for dynamic maintenance of the homeostasis of the organism during prenatal development, postnatal growth and during cyclic renewal of certain tissues. These interactions also participate in wound healing. On the other hand they play a crucial role in the process of tumor transformation,...

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