Transforming growth factor (TGF-β) and stromal-derived factor (SDF1) are reported to induce the migration of MSCs towards OS cells, while MCP-1, GRO-α, and TGF-β, in addition to effecting the chemotaxis of MSC, also induce the differentiation of MSCs into cancer-associated fibroblasts, resulting in mesenchymal-to-amoeboid transition [20]. The gene discussed is CCL2; the disease is cancer.