title: Clinical significance of serum matrix metalloproteinase-13 levels in patients with esophageal squamous cell carcinoma (ESCC).
abstract: OBJECTIVE
  Matrix metalloproteinase-13 (MMP13) is a highly regulated zinc-dependent endopeptidase and has been reported to be associated with vascular invasion and lymph node metastasis and predicts poor outcome for relatively early stage in esophageal squamous cell carcinoma (ESCC) patients. However, the role of the serum MMP-13 levels in ESCC is still unknown. In the present study, we investigate the clinical significance of MMP-13 levels in patients with ESCC.
  
  
  METHODS
  The serum level of MMP-13 was measured with commercially available ELISA kit in 112 healthy controls and 141 ESCC patients prior to surgical resection. Statistical associations between clinicopathological observations and MMP-13 levels were determined using the Mann-Whitney U test. The clinical value of MMP-13 level as a prognostic parameter was evaluated using the Cox's proportional hazards model.
  
  
  RESULTS
  The results showed compared with the healthy control group (74.5±12.3 ng/ml), ESCC patients tended to have significantly higher serum MMP-13 concentrations (86.2 ± 14.6 ng/ml) (p < 0.05). Elevation of MMP-13 levels (≥ 76.4 ng/ml) was observed in 61.7% (87/141) of patients with ESCC, and 18.4% (26/141) in healthy controls. MMP-13 levels were associated with lymph node metastasis (p < 0.001), distant metastasis (p < 0.001), histological differentiation (p = 0.026), T classification (p < 0.005), but not with the tumor size, clinical stage, age and gender of the patients or tumor location. Multivariate analysis revealed that patients with an elevated level of MMP-13 (≥ 76.4 ng/ml) had significantly lower 5 year survival rate than those with non-elevated MMP-13 (< 76.4 ng/ml, log-rank p < 0.001).
  
  
  CONCLUSIONS
  It is suggested that the elevated level of preoperative MMP-13 was found to associate with tumor progression and poor survival in patients with ESCC.
authors.affiliation: Department of Surgery, the Affiliated Hospital of Medical College, Qingdao University, Qingdao, China. qyfyzhang@126.com  
authors.forename: X-L
authors.initials: XL
authors.lastname: Jiao
authors.forename: D
authors.initials: D
authors.lastname: Chen
authors.forename: J-G
authors.initials: JG
authors.lastname: Wang
authors.forename: K-J
authors.initials: KJ
authors.lastname: Zhang
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D002294:Carcinoma, Squamous Cell / Q000097:blood* / Q000201:enzymology / Q000401:mortality / Q000556:secondary / Q000628:therapy; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D004938:Esophageal Neoplasms / Q000097:blood* / Q000201:enzymology / Q000401:mortality / Q000473:pathology / Q000628:therapy; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D008297:Male; D053509:Matrix Metalloproteinase 13 / Q000097:blood*; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012307:Risk Factors; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; C507079:MMP13 protein, human; D053509:Matrix Metalloproteinase 13