Abstract
BACKGROUND: There are inconsistencies in the use of serum or plasma when analysing the matrix metalloproteinases (MMPs) as diagnostic or prognostic markers. The purpose of this study was to compare the concentration of MMP-1, -2, -7, -8, -9 and -13 in serum vs plasma samples. METHODS: Blood samples were obtained from sixty-five men and women. Samples were analysed for levels of MMPs in corresponding citrate plasma and serum. RESULTS: All MMPs expressed higher concentration in serum compared with plasma (P<0.01). There were no differences between genders. CONCLUSIONS: Present study demonstrated significant differences regarding concentrations of some MMPs using plasma vs serum. We conclude that future studies regarding MMPs as biological markers in cancer should consider the use of citrate plasma instead of serum.