Osteosarcoma is the most frequent malignant bone tumor affecting mainly adolescents and people older than 50years old. Current treatment involves chemotherapy and surgical removal. Despite efforts... Show moreOsteosarcoma is the most frequent malignant bone tumor affecting mainly adolescents and people older than 50years old. Current treatment involves chemotherapy and surgical removal. Despite efforts to find a cure, there is 70% 5year survival rate. For patients that present metastasis at the moment of diagnosis, the prognosis is worse. Additionally, many do not respond well to chemotherapy. The aim of this research was to find new treatment options for patients with osteosarcoma. I searched for inhibitors that could sensitize osteosarcoma cells to chemotherapy. In this thesis, it is shown that targeting cell cycle regulators, proteins involved in apoptosis inhibition, and cellular pathways involved in survival, proliferation and migration are promising candidates for further research. Show less
In order to form a distant metastasis, a cancer cell has to migrate out of the primary tumor, intravasate into a blood or a lymphatic vessel, subsequently survive in the absence of cell-cell and... Show moreIn order to form a distant metastasis, a cancer cell has to migrate out of the primary tumor, intravasate into a blood or a lymphatic vessel, subsequently survive in the absence of cell-cell and cell-matrix interactions, extravasate the blood or lymphatic vessel, migrate through the target organ and finally proliferate to grow out into a full metastasis. During all of these processes, specific kinases are involved in the concerted activation of distinct signaling pathways. We hypothesised that the protein tyrosine kinase FAK plays a crucial role in one or multiple of the processes involved in the formation of metastases. Therefore, the overall aim of the studies described in this thesis was to investigate the role of the non-receptor protein tyrosine kinase FAK in the distinct processes involved in tumorigenesis and metastasis and to unravel the involved downstream signaling pathways. Moreover, the potential of a combined therapy of the inhibition of FAK and exposure to the cytostatic doxorubicin was tested, as well as dissection of the intracellular events downstream of FAK. Show less