Glioma Revisited: From Neurogenesis and Cancer Stem Cells to the Epigenetic Regulation of the Niche

Figure 1

A summary of gliomagenesis. (a) The interactions between the neurogenic niche (subventricular zone, SVZ) and neural stem cells (NSCs) highlighting the most relevant cell types and the secreted factors that affect the neural proliferation. Oligodendrocyte progenitors are more likely to undergo malignant transformation. (b) The role of cancer stem cells (CSCs) in tumor progression. There are different subpopulations of CSCs, which may contribute to tumor heterogeneity. Histone deacetylase inhibitors (HDACis) may be effective against CSCs by promoting their differentiation. The perivascular niches (PVNs) provide growth factors that enhance CSC proliferation and self-renewal. Because of the rapid tumor growth, hypoxic niches (HNs) are formed and, through the action of HIFs, secrete VEGF, which in turn may lead to new vascular niches.