Expression of Interstitial Collagenase (Matrix Metalloproteinase‐1) in Gastric Cancers

The expression of matrix metalloproteinase‐1 (MMP‐1) gene and the presence of MMP‐1 protein in gastric cancer were examined by in situ hybridization and immunohistochemistry. Expression of the interstitial Collagenase (MMP‐1) gene was detected within the stroma of the neoplastic glands, and infiltration of eosinopilic was observed to be associated with regions of MMP‐1 gene expression. The degree of eosinophils infiltration correlated with the level of MMP‐1 mRNA expression. Immunostaining showed localization of MMP‐1 protein in the stromal cells, and additionally in the neoplastic glands. These findings indicate that the stromal cells may play an important role in the expression of MMP‐1, and suggest a pathophysiological role for MMP‐1 in the invasion and metastasis of gastric cancer.