title: Serum level of DKK-1 and its prognostic potential in non-small cell lung cancer.
abstract: BACKGROUND
  The aim of the present study was to measure the serum level of dickkopf-1(DKK-1) in patients with non-small cell lung cancer (NSCLC), and to determine the prognostic potential of serum DKK-1 in NSCLC.
  
  
  METHODS
  The present study included a total of 150 patients with NSCLC and 150 healthy controls. Serum level of DKK-1 was measured by enzyme-linked immunosorbent assay (ELISA). Numerical variables were recorded as means ± standard deviation (SD) and analyzed by independent t-tests. Categorical variables were presented as rates and analyzed by using the chi-square test or Fisher's exact test. The overall survival was analyzed by log-rank test, and survival curves were plotted according to Kaplan-Meier.
  
  
  RESULTS
  We found that serum DKK-1 level was significantly higher in patients with NSCLC than healthy controls. Mean serum DKK-1 level was 31.42 ± 6.32 ng/ml in the NSCLC group and 14.12 ± 3.29 ng/ml in the healthy control group (p <0.01). Serum DKK-1 level expression level was significantly positively correlated with TNM stage (p = 0.009), lymph node involvement(p = 0.001), and distant metastases(p < 0.001).In the multivariate Cox proportional hazards analysis, high DKK-1 expression was independently associated with poor survival (P < 0.001; HR = 3.98; 95% CI =2.19-4.83).
  
  
  CONCLUSIONS
  In conclusion, our results showed that DKK-1 was overexpressed in NSCLC, and DKK-1 in serum was a good predictor of poor prognosis in patients with NSCLC. More researches are needed in the future to clarify the detailed mechanism of DKK-1 in the carcinogenesis and metastasis of NSCLC.
  The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1471414150119415.
authors.forename: Liang-liang
authors.initials: LL
authors.lastname: Dong
authors.forename: Lu-yun
authors.initials: LY
authors.lastname: Qu
authors.forename: Li-yan
authors.initials: LY
authors.lastname: Chu
authors.affiliation: Department of Medical Oncology, Yantai Yuhuangding Hospital, 20 Yuhuangding East Road, Yantai 264000, China. dr_zhangxiaohui@126.com.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Zhang
authors.forename: Ying-hui
authors.initials: YH
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000401:mortality / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000097:blood* / Q000401:mortality / Q000473:pathology; D008297:Male; D011379:Prognosis; D016016:Proportional Hazards Models
chemical_list: D014408:Biomarkers, Tumor; C501126:DKK1 protein, human; D036341:Intercellular Signaling Peptides and Proteins