FN （Fibronectin） is a glycoprotein present in a soluble dimeric form in plasma, and in a dimeric or multimeric form at the cell surface and in extracellular matrix. It is proteolytically processed to generate the mature protein. Fibronectin is involved in cell adhesion and migration processes including embryogenesis, wound healing, blood coagulation, host defense, and metastasis. In recent years, FN has been shown to play an important role in the regulation of various malignant tumors such as lung cancer, colorectal cancer, and ovarian cancer.