New genes involved in fate regulation of neural stem cells and tumorigenesis: a multidisciplinary study
Neural stem cells (NSCs) are highly undifferentiated neural precursors that retain multipotentiality i.e. the capacity to produce all the three major neural cell lineages, neurons, astroglia and oligodendroglia- all throughout life. These cells reside in discrete areas of the adult mammalian brain where neurogenesis continue throughout adulthood and generate new neurons that contribute to network plasticity and regeneration in cortical and hippocampal areas. The cell hierarchy underlying this process has been recently worked out in some detail and it entails the presence within the so called neurogenetic germinal areas of both NSCs and multipotent and unipotent (neuronal) precursors. The different precursors are characterized by the expression of specific markers as well as by precise cell cycle time and migration patterns in vivo. Once isolated from these areas and placed in cultures the NSCs adopt a proliferation mode that leads to the rapid increase of the NSCs number in vitro. The same situation applies to cancer stem cells that have recently been isolated from our laboratory from human glioblastomas which, in essence, appear to undergo a type of genetic, epigenetic and extracellular regulation resembling those in effect in their normal counterpart.
The candidates selected for this project will, therefore, contribute to all of the aspects of this work aimed at identifying novel genes that are involved in the maintenance of an undifferentiated state in normal and cancer neural stem (NSC and CNSC) cells and in regulating the acquisition of alternative neural identities and phenotypes. Candidates will be involved in isolation, expansion, characterization of NSCs. Cells will then triggered to differentiate and the pattern of differential gene expression between differentiated and undifferentiated cells will be established by gene microarray analysis. The most interesting genes will then be selected based on both the intensity of differential modulation and the putative roles with respect to specific cellular mechanisms that may be involved in NSCs and CNSCs fate and differentiation. Such role will be assessed and validated by establishing the effect of the genes upon manipulation in culture and the effects resulting by in vivo manipulation both in experimental disease models as well as in transgenic animals. This should allow for the identification of specific cellular mechanisms that may affect both normal development and be involved in the establishment of pathological conditions in the CNS. The use of state of the art culture techniques in the neural stem cell area, molecular biology, FACS sorting and in vivo transplantation will part of the training program.