The aim of this study was to correlate matrix metalloproteinase-2 and matrix metalloproteinase-9 expression with the clinicopathological features and outcome of patients with early gastric cancer and to clinically elucidate more information on the role of matrix metalloproteinase-2 and matrix metalloproteinase-9 protein overexpression with regard to lymph node metastasis of early gastric cancer. The levels of matrix metalloproteinase-2 and matrix metalloproteinase-9 protein expression were assessed by immunohistochemistry. An association was observed between matrix metalloproteinase-2, matrix metalloproteinase-9, and matrix metalloproteinase-2/matrix metalloproteinase-9 overexpression and clinicopathological factors, such as ulceration and lymph node metastasis. Furthermore, matrix metalloproteinase-9 and matrix metalloproteinase-2/matrix metalloproteinase-9 overexpression both were strongly correlated with histological grade. In addition, matrix metalloproteinase-2/matrix metalloproteinase-9 overexpression correlated with deep invasion. Multivariate Cox regression analysis revealed that matrix metalloproteinase-2 and matrix metalloproteinase-9 expression were both independent factors of overall survival in patients with early gastric cancer. In novelty, we found that matrix metalloproteinase-2/matrix metalloproteinase-9 overexpression was an independent indicator of lymph node metastasis in early gastric cancer which will be helpful in clinic to select the appropriate treatment of these patients.
