Tumor Angiogenesis: Pericytes and Maturation Are Not to Be Ignored

Figure 3

Tumor cell-derived PDGF-B induced pericyte differentiation. Incorporation of pericytes into newly formed vessels is one of the key steps to terminate angiogenesis. Studies in animal models have shown that PDGF-B is responsible for (1) differentiation of pericytes from mesenchymal stem cells through the PDGF-B-NRP-1 signaling pathway (2) increased recruitment and attachment of newly differentiated pericytes into newly formed tumor vessels. In addition, Flk1+ cells differentiate into endothelial cells or pericytes upon stimulation by VEGF or PDGF-B [72].