Matrix metalloproteinase-2 expression in laryngeal preneoplastic and neoplastic lesions

Matrix metalloproteinase-2 (MMP-2), a member of gelatinases, is particularl y important in the digestion of nonfibrillary and denaturated collagens; th us, it may play a role in tissue remodeling and in the invasion of malignan t cells. The expression of MMP-2 has not yet been described in preneoplasti c lesions of the larynx thus far. The purpose of this study was to evaluate whether the expression of MMP-2 plays a role in early laryngeal carcinogen esis. Laryngectomy specimens of 20 invasive carcinoma cases were studied. The sli des with atypical hyperplasia, carcinoma in situ, and invasive carcinoma we re selected from laryngectomy specimens. On these slides, 23 atypical hyper plasia and 17 carcinoma in situ areas were identified. MMP-2 expression was scored immunohistochemically on paraffin tissue sections using the avidin- biotin-peroxidase method. MMP-2 expression in all three groups was statistically different. A sequent ial increase in MMP-2 expression correlated significantly with the hypothes is of multistep carcinogenesis. In contrast, MMP-2 expression was not relat ed to tumor stage, lymph node metastasis, or differentiation in squamous ce ll carcinomas. In conclusion, this sequential increase in MMP-2 expression points to an al tered expression of MMP-2 in early neoplastic transformation in laryngeal m ucosa, followed by an increasing expression during the progression of the d isease.