Analysis of Expression of Matrix Metalloproteinases-2 and −9 in Hypopharyngeal Squamous Cell Carcinoma by in Situ Hybridization

The gene expression of two type IV collagenases (matrix metalloproteinase [MMP]-2, a 72 kd type IV collagenase, and MMP-9, a 92 kd type IV collagenase) was investigated in carcinomas of the hypopharynx. We examined 27 cases operated on in our hospital by an in situ hybridization technique to detect their messenger RNA signals in cancer cells and surrounding stroma. Both signals were detected in all cancer nests and in stromal cells in the same specimens. Clinicopathologic studies showed a significant relationship between MMP-2 expression in the primary cancer and the outcome of treatment. Our present study suggests that hypopharyngeal squamous cell carcinoma producing MMP-2 has a high potential for invasion and metastasis and a poor outcome. The analysis of MMPs will be useful for treatment planning in hypopharyngeal carcinoma and for prognosis.