NANOG and glioblastoma: MiR-134 is a brain-enriched miRNA that plays an essential role in the development of the embryonic stem cell-orientated differentiation to central nervous system by suppression of Nanog and neural development (including neurons, cylindraxile and dendrites) and has been shown to be downregulated in oligodendrogliomas (ODG) and glioblastomas (GBM), suggesting its possible involvement in brain tumor progression.