Fig. 4
From: Targeting cancer stem cell pathways for cancer therapy
The microenvironment of cancer stem cells. Proliferation, self-renewal, differentiation, metastasis, and tumorigenesis of CSCs in the CSC microenvironment. The CSC microenvironment is mainly composed of vascular niches, hypoxia, tumor-associated macrophages, cancer-associated fibroblasts, cancer-associated mesenchymal stem cells, and extracellular matrix. These cells in response to hypoxic stress and matrix induce growth factors and cytokines (such as IL-6 and VEGF) to regulate the growth of CSCs via Wnt, Notch, and other signaling pathways
