IGFBP7 and thyroid gland carcinoma: Notably, while four out of five mice inoculated with vector control WRO cells presented detectable tumor xenografts, only two out of five mice inoculated with WRO-IGFBP7 cells presented tumor growth (Fig. 3b), suggesting that IGFBP7 overexpression apparently suppressed not only the tumor growth rate, but also the tumorigenicity of thyroid cancer cells.