Cancer Stem Cells and Macrophages: Implications in Tumor Biology and Therapeutic Strategies

Figure 2

The CSC niche and tumor microenvironment. At center stage is the CSC, in contact with a complex and dynamic cellular network, including daughter cancer cells, stellate cells (in the case of HCC and PDAC), cancer-associated fibroblasts (CAFs), and immune cells, which include T-cells, monocytes, neutrophils, and tumor-associated macrophages (TAMs). Nourished by the circulatory system, these cells communicate with one another and directly with the CSC via secreted factors, forming a positive feedback loop that promotes CSC tumorigenicity and metastasis.