EXPRESSION OF MMP-1, TIMP-1, AND TYPE-I COLLAGEN IN LARYNGEAL CARCINOMA

Matrix metalloproteinases (MMPs) are thought to play an important role in tumor invasion and metastasis. To our knowledge, however, no previ ous report examined the histologic localization of matrix metalloprote inase-l (MMP-1), tissue inhibitor of metalloproteinase-l (TIMP-1) and Type I collagen in laryngeal carcinoma from the same samples. In this study, immunohistochemical staining for MMP-1, TIMP-1, and Type I coll agen was performed on paraffin-embedded sections from 83 laryngeal squ amous cell carcinomas. Twenty of the 83 tumors were examined for MMP-1 and TIMP-1 mRNA using in sial hybridization (ISH). Immunohistochemica l and ISH analyses indicated that squamous cancer cells as well as str omal cells such as fibroblasts, macrophages, and mononuclear and endot helial cells expressed MMP-1 and TIMP-1 in the area adjacent to the tu mor. The localization of MMP-1 and TIMP-1 protein is similar to that o f their respective transcripts. Dense or moderate patterns of Type I c ollagen were associated with a tendency toward positivity for TIMP-1 a nd negativity for MMP-1 (P <.002). A sparse pattern of Type I collagen was associated with a tendency toward positivity for MMP-1 and negati vity for TIMP-1 (P <.004). The patterns of Type I collagen staining co rrelated significantly with imbalances in MMP-1 and TIMP-1 expression (P <.001). Matrix degradation and remodeling in squamous cell carcinom a of the larynx might be attributable to an imbalance in the expressio n of MMP-1 and TIMP-1.