Serum levels of matrix metalloproteinase-2 and-9 in patients with head andneck squamous cell carcinoma

Background: Matrix Metalloproteinases (MMPs) have been implicated as playin g an important role in cancer invasion and metastasis. MMPs have been ident ified in a wide variety of malignancies including head and neck squamous ce ll carcinomas (HNSCC). Material and Methods: We investigated the circulatin g level of MMP-2 (gelatinase A ol 72-kD type IV collagenase) and MMP-9 (gel atinase B or 92-kD type IV collagenase) in sera from patients with various head and neck squamous cell carcinomas (n=86) as well as from healthy norma l controls (n=47). Serum MMP concentrations were determined as serum immuno reactivity by using a quantitative sandwich enzyme immunoassay technique. F or statistical analysis, the t-test and Kruskal-Wallis test were performed. Results: The majority of the patients with HNSCC were found to have high c oncentrations of serum MMP-9. The levels of MMP-9 in the sera of patients w ith cancer ranged from 39 to 1547 ng/ml (mean, 417 ng/ml). In contrast, the MMP-9 serum levels in 47 healthy individuals ranged from 30 to 537 ng/ml ( mean, 189 ng/ml), MMP-9 serum concentration being significantly higher in H NSCC patients (p=0.001). MMP-9 serum concentrations of patients with advanc ed stage HNSCC were significantly higher (p=0.0449) compared to patients wi th early stage cancer. No significant difference of MMP-2 serum levels was seen when comparing HNSCC patients and normal controls. Conclusion: The pre sent data indicate that the elevation of serum levels of MMP-9, but not MMP -2 may be a useful market for clinical monitoring of HNSCC patients.