found that PCa cells provide osteoblasts with osteogenic cytokines [e.g. bone morphogenetic proteins (BMPs), platelet-derived growth factors (PDGF), endothelin-1 (ET1)] and osteolytic factors [e.g. MMPs and vascular endothelial growth factor (VEGF)], which enables these cells to make bone-derived cell growth factors (211). Here, EDN1 is linked to posterior cortical atrophy.