ABSTRACT
A common component of the newly deposited tumor-associated matrix is the macromolecule hyaluronan, a glycosaminoglycan polysaccharide more commonly associated with embryonic connective tissues. Hyaluronan is a high-molecular-weight, nonsulfated glycosaminoglycan present in the extracellular matrix of most animal tissues. During specific morphogenic events, high concentrations of hyaluronan are selectively deposited within the extracellular matrix which, in turn, becomes highly hydrated and expands due to increased osmotic pressure. Hyaluronan serves a role in facilitating cell migration during tumor invasion, as it does in embryonic tissues, it would appear that the requirement for hyaluronan is closely related to the particular tissue stroma undergoing invasion. The cell type responsible for increased production of tumor-associated hyaluronan, and how that production is regulated, remains under investigation. Tumor cells that express hyaluronan receptors may directly interact with hyaluronan within tumor extracellular matrix as a support for locomotion or as a stimulus to induce migratory cell behavior.
