Immunohistochemical and clinical significance of matrix metalloproteinase-2 and its inhibitor in oral lichen planus.

BACKGROUND

Matrix metalloproteinases (MMP) are being considered important mediators in cancer invasion, and plenty of research is in progress. Our objective was to evaluate the presence of MMP-2 and tissue inhibitor of metalloproteinase (TIMP-2) in oral lichen planus (OLP) and to assess its role in the pathogenesis of OLP and as an indicator of malignant transformation.

MATERIALS AND

METHODS

Immunohistochemical analysis for MMP-2 and TIMP-2 was performed in thirty histopathologically confirmed, formalin-fixed, paraffin-embedded specimens of OLP (24 cases of reticular and 6 cases of erosive LP). A semi-quantitative analysis was done to assess the expression and distribution of this marker in these lesions.

RESULTS

In all cases of OLP, MMP-2 expression was seen mainly in areas of lymphocytic inflammatory infiltrate (100%) in the lamina propria within the overlying epithelium. TIMP-2 expression was seen more than 50% in the fibroblasts and basal and parabasal cells.

CONCLUSION

The expression of MMP-2 and TIMP-2 was observed in all cases of OLP. However, a clinical 5-year follow-up of the lesion revealed no progression of the disease except for chronic exacerbation and regression of these lesions. Although our study considers MMP-2 and TIMP-2 as mediators in the pathogenesis of OLP, it still remains debatable whether they have a direct role to play in the disease process or whether they are suitable biomarkers to assess the disease progression.