Similar results are documented by Bussard and colleagues showing an increased presence of osteoblast-derived cytokines including IL-6, IL-8, MCP-1, macrophage-inflammatory protein 2 (MIP-2), and vascular endothelial growth factor (VEGF) in the presence of MDA-MB-231 breast cancer cells in ex vivo cultures of tumor bearing bones from athymic mice, or even in the presence of conditioned medium in vitro (34). The gene discussed is IL6; the disease is breast cancer.