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

Abstract

In 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.