Expression of matrix metalloproteinase-9 in gastric cancer and its prognostic significance

LI Xiaoshan; XU Qing; FU Xiangyang; LUO Weisheng

Abstract：Objective To investigate the expression of matrix metalloproteinase-9( MMP-9) in gastric cancer and evaluate its relation ship with clinicopathological characteristics and prognosis of gastric cancer. Methods The expression of MMP-9 in 101 gastric cancer patients was determined by immunohistochemistry. The relationship between MMP-9 with clinicopathological characteristics and prognosis in gastric cancer was analyzed. The patients were followed up and recurrence-free survival ( RFS) and overall survival ( OS) were estimated using the Kaplan-Meier method, while factors influencing prognosis were tested by Cox proportional harzard model. Re-sults Overexpression rate of MMP-9 was 54?5% of gastric cancer samples, higher than 15?5% of adjacent normal tissue( P<0?001) . The expression of MMP-9 was closely related to tumor size, tumor site, tumor invasion, lymph node metastasis and clinical stage in gastric cancer samples ( P<0?05) . The median RFS and OS of 101 patients were 28?0 and 35?0 months, respectively. Moreover, the patients with MMP-9 lower expression had better RFS and OS than those with MMP-9 overexpression ( 63?0 vs. 11?0 months, 65?0 vs. 17?0 months;P<0?001) . The multivariate Cox proportional hazard regression analysis of prognostic factors for RFS and OS showed that the expression of MMP-9, tumor size, lymphnode metastasis were independent factors for prognosis of gastric cancer. Conclusion The expression of MMP-9 is correlated with tumor invasion and metastasis, and it can be a powerful molecular marker to predict the progro-sis of gastric cancer.