title: Serum Cripto-1 is a novel biomarker for non-small cell lung cancer diagnosis and prognosis.
abstract: BACKGROUND
  Cripto-1 (CR-1) is highly expressed in several different types of human tumors. However, the clinical significance of CR-1 expression in serum specimens from non-small cell lung cancer (NSCLC) patients has not yet been determined.
  
  
  OBJECTIVE
  The aim of this study was to explore the diagnostic and prognostic value of serum CR-1 levels in patients with NSCLC.
  
  
  METHODS
  Serum specimens from 592 NSCLC patients, 180 benign lung disease patients and 240 healthy controls were collected. The concentrations of CR-1 were measured by sandwich enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Patients with NSCLC had higher serum CR-1 levels than the controls (P < 0.01) and patients with benign lung diseases (P < 0.01). When a cutoff point of 1.8 ng/mL was selected (diagnostic specificity 95%), the diagnostic sensitivity for NSCLC is 56.8%. About 37.5% of carcinoembryonic antigen (CEA)-negative lung cancer patients were CR-1 positive at 95% specificity. In patients with stage I/II lung cancer, use of these two markers in combination results in almost 21% increase in sensitivity, at 95% specificity, compared with CEA alone. Uni-variate analysis revealed that NSCLC patients with positive CR-1 had a shorter overall survival (OS) and progression-free survival (PFS) than those with negative CR-1 [hazard ratio (HR) of 2.93, P = 0.005; HR of 2.12, P = 0.005]. Cox multi-variate analysis indicated that CR-1 was an independent prognostic indicator of PFS and OS (HR of 1.91, P = 0.006; HR of 1.82, P = 0.007). Kaplan-Meier survival curves further confirmed that patients with negative CR-1 had longer PFS and OS (P = 0.026 and P = 0.011, respectively).
  
  
  CONCLUSIONS
  In conclusion, measurement of serum CR-1 is a useful diagnostic and prognostic marker for NSCLC patients.
authors.affiliation: Department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, China.|Clinical Center of Nanjing Respiratory Diseases and Imaging, Nanjing, China.
authors.forename: Chun Hua
authors.initials: CH
authors.lastname: Xu
authors.affiliation: Department of Radiology, Nanjing Chest Hospital, Nanjing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Respiratory Medicine, Nanjing Pukou Central Hospital, Nanjing, China.
authors.forename: Li Hua
authors.initials: LH
authors.lastname: Qian
authors.affiliation: Department of Respiratory Medicine, Nanjing Chest Hospital, Nanjing, China.|Clinical Center of Nanjing Respiratory Diseases and Imaging, Nanjing, China.
authors.forename: Li Ke
authors.initials: LK
authors.lastname: Yu
authors.affiliation: Department of Respiratory Medicine, Nanjing Jiangning Hospital, Nanjing, China.
authors.forename: Xiu Wei
authors.initials: XW
authors.lastname: Zhang
authors.affiliation: Department of Geriatrics Medicine, Nanjing Second Hospital, Nanjing, China.
authors.forename: Qing Bo
authors.initials: QB
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D002272:Carcinoembryonic Antigen / Q000097:blood; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000401:mortality* / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D058851:GPI-Linked Proteins / Q000097:blood*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008168:Lung / Q000473:pathology; D008175:Lung Neoplasms / Q000097:blood* / Q000401:mortality* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000097:blood*; D009367:Neoplasm Staging; D011379:Prognosis; D016019:Survival Analysis
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D058851:GPI-Linked Proteins; D036341:Intercellular Signaling Peptides and Proteins; D009363:Neoplasm Proteins; C070636:TDGF1 protein, human
keywords: Cripto-1; biomarker; diagnosis; non-small cell lung cancer; prognosis