Matrix Metalloproteinase-2 and -7 Expression in Colorectal Cancer

PURPOSE: Matrix metalloproteinase-2 (MMP-2) and MMP-7 have been implicated in tumor growth and metastasis. This study aimed to investigate the expressions of MMP-2 and -7 in colorectal cancer and to evaluate their values as prognostic markers. METHODS: Immunohistochemical staining for MMP-2 and -7 was done in 144 resected colorectal cancer specimens. Clinicopathological data and survival results were compared with regard to the expression results. RESULTS: The expression rates of MMP-2 in tumor cells in the tumor center and the tumor border were 16.7% and 38.9%, respectively. That of MMP-2 in stromal cells was 27.8%. MMP-7 immunoreactivities of tumor cells in the tumor center and the tumor border were 6.9% and 23.6%. The expressions of MMP-2 and MMP-7 were correlated. MMP-2 expression in stromal cells was more increased in the distal part of the colorectum: 8.8% in right colon cancer, 29.5% in left colon cancer and 36.4% in rectal cancer. MMP-2 expression of tumor cells in the tumor border was correlated with T-stage. MMP-7 expression of tumor cells in the tumor border was increased in case of infiltrative cancer compared with fungating tumor. The expression patterns of MMP-2 and -7 were not correlated with other clinicopathological factors, including tumor markers, node metastasis, distant metastasis, lymphatic invasion, tumor differentiation, and recurrence. No significant associations between the overall and disease-free survival rates and the MMP-2 and -7 expression patterns were noted. CONCLUSION: The high expression rates of MMP-2 and -7 in tumor borders suggest that MMP-2 and -7 have some role in tumor invasion, but in this study, MMP-2 and -7 did not appear to be significant predictors of prognosis in colorectal cancer.