Wound healing and
tumor stroma generation share several important properties, including hyperpermeable blood vessels, extravasation of
fibrinogen, and extravascular clotting. In both, the deposits of
fibrin gel serve initially as provisional stroma and later are replaced by granulation tissue.
Proteoglycans (PG) are also important constituents of the extracellular matrix, but their composition and role in healing
wounds and
tumor stroma generation are poorly understood. The authors used immunohistochemical and biochemical methods to investigate the
dermatan sulfate proteoglycan (
DSPG) and
chondroitin sulfate proteoglycan (CSPG) composition of healing skin
wounds and solid
tumors. By immunohistochemistry, the great majority of normal guinea pig and human dermis stained weakly for CSPG and strongly for
decorin. In contrast, the granulation tissue of healing skin
wounds and
scars stained intensely for CSPG and weakly or not at all for
decorin; however
decorin staining was restored to normal intensity after digestion with
chondroitin ABC lyase, suggesting that
decorin antigenic sites had been masked by
glycosaminoglycan (GAG) chains. Like
wounds, the stroma of several
carcinomas (line 1 guinea pig, human breast, colon, basal cell, and squamous) stained strongly for CSPG and weakly or not at all for
decorin, but
decorin staining developed after
chondroitin ABC lyase digestion. Thus healing
wounds and
tumor stroma express a common pattern of altered PG staining, adding another to the properties these pathologic entities share.
Proteoglycans extracted from healing
wounds after in situ labelling with [35S] Na
sulfate contained more CSPG than normal dermis with significantly longer GAG chains. Granulation tissue also synthesized more
DSPG than normal skin, with greater heterogeneity and longer GAG chains. These alterations in PG synthesis correlate with the cell proliferation, migration, and
collagen synthesis that accompany wound healing and may provide clues to the mechanisms responsible for both wound healing and
tumor stroma generation.