Abstract:

BACKGROUND: Cell cycle has proved that about 90% stem cells were in resting state in the G0 phase; therefore, serum deprivation method which did not contain any growth factors and related nutrition additive was beneficial for separating glioma stem cells.
OBJECTIVE: To explore the method of serum deprivation to culture glioma cell lines U87, and to isolate and identify the cancer stem cells which are in the U87 cell lines.
METHODS: U87 cells were cultured in the medium containing both DMEM and L-glutamine for six days; cancer stem cells would be screened out; then the medium was changed for the neural stem cell culturing medium. The formation of tumor spheres and their differentiation characteristics were observed when they were inoculated onto serum-containing medium. The immunofluorescence staining of cells was employed to identify the surviving cells cultured in serum deprivation medium, tumor spheres and differentiated cells.
RESULTS AND CONCLUSION: The serum deprivation method was used to select tumor stem cells successfully which expressed CD133 and could form tumor spheres. The tumor spheres had an ability of multi-differentiations, and the daughter cells expressed glial fibrillary acidic protein and neuron specific enolase. The U87 cell lines exist glioma stem cells which have the capacities of self-renewal and multi-differentiation.