Treatment of highly metastatic murine melanoma cells B16F10 with curcumin (15 microM) for 15 days significantly inhibited matrixmetalloproteinase-2 (MMP-2) activity. Expression of membrane type-1 matrix metalloproteinase (MT1-MMP) and focal adhesion kinase (FAK), an important component of the intracellular signalling pathway, were also reduced to almost background levels. MMP-2, MT1-MMP and FAK did not return to control levels even after 28 days of drug withdrawal. However, effect of curcumin on ligand binding property of integrin receptors was reversible. Downregulation of FAK (which would impair integrin mediated signal transduction cascade) and reduction of MMP-2 activity could be important reasons for anti-metastatic property of curcumin.