IGFBP1 and cancer: In particular, growth-regulated protein (GRO), ENA-78/CXCL5, TIMP-2, and leptin were strongly up-regulated in malignant seroma, whereas IGFBP-1 (insulin-like factor binding protein-1), IL-3, IFN-γ, FGF-9 and IL-16 were down-regulated in malignant versus benign seroma fluid (Figs. 2a, b,  3a–c).