title: Elevated pleural effusion IL-17 is a diagnostic marker and outcome predictor in lung cancer patients.
abstract: BACKGROUND
  Interleukin 17 (IL-17) is a proinflammatory cytokine produced mainly by CD4(+) T-lymphocytes and may be important in tumor cell growth and progression. In this study, we aimed to evaluate the diagnostic and prognostic value of pleural effusion levels of IL-17 in lung cancer patients with malignant pleural effusion (MPE).
  
  
  METHODS
  Pleural effusion samples were collected from 78 lung cancer patients with MPE and from 45 patients with nonmalignant pleural effusion. Pleural fluid concentrations of IL-17 were measured by using enzyme-linked immunosorbent assays.
  
  
  RESULTS
  Malignant effusion exhibited higher IL-17 levels than nonmalignant effusion (20.49 ± 5.27 pg/ml vs. 13.16 ± 2.25 pg/ml; P < 0.01). Lung cancer patients with pleural fluid IL-17 levels below 15 pg/ml had longer overall survival than those patients with higher levels (10.8 months vs. 4.7 months; P < 0.05). On the basis of multivariate analysis, we found that pleural fluid IL-17 level was an independent prognostic factor in lung cancer patients with MPE.
  
  
  CONCLUSIONS
  Measurement of IL-17 levels might be a useful diagnostic and prognostic test for lung cancer patients with MPE.
authors.forename: ChunHua
authors.initials: C
authors.lastname: Xu
authors.affiliation: First Department of Respiratory Medicine, Nanjing Chest Hospital, 215 Guangzhou Road, Nanjing 210029, China. yulike_doctor@163.com.
authors.forename: LiKe
authors.initials: L
authors.lastname: Yu
authors.forename: Ping
authors.initials: P
authors.lastname: Zhan
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D020381:Interleukin-17 / Q000032:analysis / Q000096:biosynthesis*; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D016066:Pleural Effusion, Malignant / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D016016:Proportional Hazards Models
chemical_list: D014408:Biomarkers, Tumor; D020381:Interleukin-17