TGFB1 and cancer: MSCs can be induced to migrate to OS by transforming growth factor (TGF-β) and stromal-derived factor (SDF1), and MSCs can also be induced to differentiate into cancer-associated fibroblasts (CAF) by monocyte chemoattractant protein (MCP)-1, growth-regulated oncogene-α (GRO-α) and transforming growth factor (TGF)-β1 (Figure 3; Table 1).