Suppression of local invasion of ameloblastoma by inhibition of matrix metalloproteinase-2 in vitro.

<bold>Background: </bold>Ameloblastomas are odontogenic neoplasms characterized by local invasiveness. This study was conducted to address the role of matrix metalloproteinase-2 (MMP-2) in the invasiveness of ameloblastomas.<bold>Methods: </bold>Plasmids containing either MMP-2 siRNA or tissue inhibitor of metalloproteinase-2 (TIMP-2) cDNA were created and subsequently transfected into primary ameloblastoma cells. Zymography, RT-PCR, and Western blots were used to assess MMP-2 activity and expression of MMP-2 and TIMP-2, as well as protein levels.<bold>Results: </bold>Primary cultures of ameloblastoma cells expressed cytokeratin (CK) 14 and 16, and MMP-2, but only weakly expressed CK18 and vimentin. MMP-2 mRNA and protein levels were significantly inhibited by RNA interference (P < 0.05). Both MMP-2 siRNA and TIMP-2 overexpression inhibited MMP-2 activity and the in vitro invasiveness of ameloblastoma.<bold>Conclusion: </bold>These results indicate that inhibition of MMP-2 activity suppresses the local invasiveness of ameloblastoma cells. This mechanism may serve as a novel therapeutic target in ameloblastomas pursuant to additional research. [ABSTRACT FROM AUTHOR]