The significance of matrix metalloproteinases-2,9 in the expression of human middle ear cholesteatoma.

Objective To explore the expression of matrix metalloproteinase-2,9 (MMP-2,MMP-9) and their clinical significance in human middle ear cholesteatoma. Methods Immunohistochemical S-P method was used to examine the expression of MMP-2?MMP-9 in 34 cases of acquired middle ear cholesteatoma and 10 cases of normal external acoustic meatus skin. Results It was found that the positive rates of MMP-2 and MMP-9 in 34 cases of middle ear cholesteatoma were 85.3%(29/34) and 91.2%(31/34)respectively. There was significant difference of the expression of MMP-2 and MMP-9 between cholesteatoma and external acoustic meatus skin (anterior P0.05,posterior P0.01). The stain in cholesteatoma was stronger than that in external acoustic meatus skin. The positive expression of MMP-2 and MMP-9 were mostly middle and strong, expressions of MMP-2 and MMP-9 were observed in all layers of the epithelial cells in cholesteatoma and the stain was strongest in basement membrane. Conclusion The results showed that the expressions of MMP-2 and MMP-9 are associated with bone destruction in middle ear cholesteatoma.