IBSP and thyroid gland papillary carcinoma: The study of co-expression of bone sialoprotein, integrin αVβ3, and MMP-2 in papillary thyroid carcinoma cells demonstrated that cancer cells appear to become more invasive when bone sialoprotein forms a cell-surface trimolecular complex that links MMP-2 to integrin αVβ3 (Karadag et al. 2004).