Fibronectin is an adhesive glycoprotein with a molecular mass of 440 kDa. It is believed to be important for the formation of a provisional matri, Xenopus/Amphibian, that promotes cell adhesion and migration during wound healing. Its age-dependent increase in plasma and tissues may be accompanied in pathological states, especially in tumor growth, by its proteolytic breakdown by a number of neutral proteases. It has also shown that several of its proteolytic breakdown products e, Xenopus/Amphibian,hibit une, Xenopus/Amphibian,pected and mostly harmful biological activities.