title: Elevated Matrix Metalloproteinase-9 Expression Correlates With Advanced Stages of Oral Cancer and Is Linked to Poor Clinical Outcomes.
abstract: OBJECTIVE
  Using a meta-analytic approach, the relation between increased matrix metalloproteinase-9 (MMP-9) expression, tumor stage, and clinical outcomes in oral cancers was investigated.
  
  
  METHODS
  Multiple English- and Chinese-language electronic databases were searched to identify high-quality case-and-control studies relevant to this meta-analysis. Methodologic quality of the included trials was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology statement to ensure consistency in reviewing and reporting the results. Statistical analyses were carried out with STATA 12.0 statistical software.
  
  
  RESULTS
  Nine case-and-control studies containing a combined total of 419 patients with oral cancer were included in the present meta-analysis. Results showed that patients who were positive for MMP-9 expression had a significantly poorer overall survival compared with those negative for MMP-9 (effect size = 2.10; 95% confidence interval, 0.98 to 3.22; P < .001). MMP-9 expression also positively correlated with lymph node metastasis and advanced T-stage groups (P < .05 for all comparisons). Further, high MMP-9 expression level correlated with increased oral cancer risk in Asians (P < .05 for all comparisons) as shown by method-stratified subgroup analysis.
  
  
  CONCLUSIONS
  The present results strongly suggest that MMP-9 expression level influences tumor invasion and metastasis in oral cancers. Based on these results, MMP-9 can be an excellent therapeutic target in patients with oral cancer.
authors.affiliation: Researcher, Department of Stomatology, General Hospital of the Chengdu Military Command, Chengdu, China.
authors.forename: Wei-Yin
authors.initials: WY
authors.lastname: Zheng
authors.affiliation: Researcher, Department of Respiratory Medicine, General Hospital of the Chengdu Military Command, Chengdu, China. Electronic address: zhangdingtao813@163.com.
authors.forename: Ding-Tao
authors.initials: DT
authors.lastname: Zhang
authors.affiliation: Researcher, Department of Stomatology, General Hospital of the Chengdu Military Command, Chengdu, China.
authors.forename: Shu-Yong
authors.initials: SY
authors.lastname: Yang
authors.affiliation: Researcher, Department of Stomatology, General Hospital of the Chengdu Military Command, Chengdu, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
mesh_terms: D015415:Biomarkers / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000175:diagnosis* / Q000201:enzymology; D011379:Prognosis; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D020780:Matrix Metalloproteinase 9