Clinical significance of matrix metalloproteinase-7 expression in esophageal carcinoma

Matrix metalloproteinase-7 (MMP-7) is a member of MMP family and has a wide variety of substrate spectra. It is reported to play an important role in carcinoma invasion and metastasis. There is, however, little information on the clinical significance of MMP-7 in human esophageal carcinoma. We thus studied 48 tumor/normal pair samples of human esophagus by Northern blot analysis. The results demonstrated that the tumor tissue (T) of esophageal carcinoma showed a higher expression of MMP-7 mRNA than the corresponding normal tissue (N) in 31 cases (65%). We also statistically evaluated tumor MMP-7 value (T value) corrected for MMP-7-positive control (KYSE150 transfected with the MMP-7 gene). Fourteen cases with T value ≥ 0.3 showed a higher frequency of lymph node metastasis than 34 cases with T value < 0.3 (P < 0.05). The cases with T value ≥ 0.3 showed a significantly poorer prognosis than those with T value < 0.3 (P < 0.01). Multivariate analysis demonstrated that the MMP-7 expression status was the independent factor relating to the prognosis (P = 0.0005). The findings indicated that MMP-7 might be a novel prognostic factor for patients with esophageal carcinoma.