The Clinical Utility of Matrix Metalloproteinase 9 in Evaluating Pathological Grade and Prognosis of Glioma Patients: A Meta-Analysis

IIn the recent years, matrix metalloproteinase 9 (MMP-9) has been focused on as an indicator of glioma grade and prognosis, especially in China. However, all results resulted in many conflicts. So, it is necessary to conduct a meta-analysis to secure a convincing correlation between MMP-9 and grade and prognosis. Eligible studies were included via multiple searches, and then odds ratios (ORs) and hazard ratios (HRs) with 95 % confidence intervals (95 % CIs) were estimated. Funnel plots were available for evaluation of publication bias. In addition, heterogeneity and sensitivity were also analyzed. In the present meta-analysis, 23 articles were allowed for inclusion with total 1,635 patients. Coincidentally, all studies were conducted in Chinese populations. High MMP-9 expression in gliomas was closely associated with high WHO grade (III+ IV) (n=22, OR=5.25, 95 % CI=4.09-6.73; p=0.000), while MMP-9 expression did not correlate to age (n=4, OR=1.02, 95 % CI=0.67-1.54; p=0.929) and gender (n=5, OR=0.91, 95 % CI=0.63-1.33; p=0.632). Besides, overall survival analysis from two articles revealed MMP-9 expression significantly predicted 5-year-OS (HR=6.44, 95 % CI=3.88-10.70; p=0.000) in glioma patients. No heterogeneity and publication bias were observed across all studies. To conclude, this meta-analysis suggests MMP-9 is potently associated with high grade and poor 5 years prognosis, and MMP-9 test of glioma tissues should be established in department of pathology as a routine in clinical practice.