The significance of plasminogen activators and matrix metalloproteases for
clinical outcome, growth and metastatic behavior of head and neck squamous
cell carcinoma (SCC) is still controversial. The majority of studies has be
en based on either immunohistological stainings, which provide only limited
quantitative information, or in vitro experiments. We analyzed 44 head and
neck; SCC and 11 mucosa tissue samples for the expression of gelatinolytic
or fibrinolytic proteases by quantitative zymographic analysis and compare
d lytic activities to clinical and histopathological data. We calculated ac
tivation ratios for matrix metalloproteinases-2 and -9 (MMP-2 and MMP-9) by
separate evaluations of inactive and activated MMP forms. Increased gelati
nolytic and fibrinolytic activity was found in head and neck SCC when compa
red to mucosa. Increased values were caused by MMP-9 and urokinase type pla
sminogen activator, respectively. No statistically significant correlations
of either protease lytic activity or activation ratio could be related to
T-stage, metastasis, tissue necrosis or the differentiation stage of tumors
. The data recorded are compared with previously published reports.