Clinical significance of matrix metalloproteinase-2 in endometrial cancer: A systematic review and meta-analysis

BACKGROUND: Matrix metalloproteinase-2 (MMP-2), a member of the zinc-dependent metalloproteinase gene family, plays a vital role in cancer invasion, metastasis, and progression. This systematic review and meta-analysis aims to explore the clinical significance of MMP-2 expression in endometrial cancer. METHODS: PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure databases were systematically searched up to September 30, 2017, supplemented by manual searches of bibliographies. Two reviewers independently identified articles, extracted data, assessed quality, and cross-checked the results. Meta-analysis was conducted to explore the difference in the positive rate of MMP-2 expression between patients with endometrial cancer and those with endometriosis or normal endometrium, and to investigate the associations of MMP-2 expression with clinicopathologic characteristics of patients with endometrial cancer. Weighted mean differences and risk ratios (RRs) with 95% confidence interval (CI) were calculated for continuous and dichotomous variables, respectively. RESULTS: Totally 20 studies were selected for this systematic review and meta-analysis. Compared with those with endometriosis or normal endometria, the positive rate of MMP-2 expression is significantly higher in patients with endometrial cancer (RR = 2.31, 95% CI: 1.78–3.00, P < .01). MMP-2 expression was significantly associated with Federation of Gynecology and Obstetrics stage (RR = 1.19, 95% CI: 1.09–1.31, P < .01), histologic grade (RR = 1.10, 95% CI: 1.01–1.19, P = .02), lymph node metastasis (RR = 1.32, 95% CI: 1.15–1.51, P < .01), and myometrial invasion (RR = 1.25, 95% CI: 1.12–1.38, P < .01). CONCLUSION: The results showed that MMP-2 was expressed in high percentage of endometrial cancer and its expression may be associated closely with clinical stage, and tumor invasion and metastasis, indicating that MMP-2 overexpression may serve as a predictive factor for poor prognosis of endometrial cancer.