| The cell of origin of brain tumours is unknown and determinants of brain tumour phenotype are poorly understood. Evidence suggests a neural stem cell is the target for transformation leading to a brain tumour. In this thesis, we established a model system to test whether neural stem cells may be transformed and driven down a particular differentiation pathway. Neural stem cells, cultured as neurospheres, were retrovirally infected in vitro with a brain tumour derived oncogene, EGFRvIII; an oncogenic form of epidermal growth factor receptor (EGFR) found in human malignant astrocytomas. The effect of EGFRvIII on neural stem cell self renewal, proliferation, differentiation and migration was studied. Results suggest that EGFRvII increases self renewal and proliferation of cells, and may alter neural stem cell differentiation and migration. The results establish an experimental model which explores early stages of brain tumorigenesis through expression and analysis of oncogenes in neural stem cells. |
