title: Serum angiopoietin-2 as a clinical marker for lung cancer.
abstract: BACKGROUND
  Angiopoietins play a critical role in the angiogenesis related to tumor growth in concert with vascular endothelial growth factor (VEGF), and enhanced expression of angiopoietin-2 has been reported in lung cancer tissue.
  
  
  METHODS
  Patients with lung cancer (n = 136) and healthy volunteers (n = 40) were enrolled. Serum angiopoietin-2 and VEGF concentrations were measured using enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Patients with lung cancer had higher serum angiopoietin-2 (2,046.3 +/- 1,171.3 pg/mL vs 1,269.8 +/- 494.1 pg/mL, p < 0.001) and VEGF (542.9 +/- 445.8 pg/mL vs 364.7 +/- 185.9 pg/mL, p < 0.05) [mean +/- SD] levels than the control group. Serum angiopoietin-2 and VEGF levels correlated with each other in patients with lung cancer (Spearman r = 0.30, p < 0.001), specifically in non-small cell lung cancer (NSCLC) [n = 110; r = 0.34; p < 0.001] but not in small cell lung cancer (n = 26). With stage progression in NSCLC, serum angiopoietin-2 levels increased, and patients with distant metastasis had higher levels than those without metastasis (p < 0.005). By contrast, serum VEGF level did not increase with stage progression, and only had a trend toward elevation in distant metastasis (p = 0.05). In NSCLC, the low angiopoietin-2 group (< 1,605.5 pg/mL) had a better overall survival compared to the high angiopoietin-2 group (> or = 1,605.5 pg/mL; p < 0.05), although this survival benefit was not maintained after controlling for stage in a multivariate analysis. The angiopoietin-2 levels were higher in NSCLC patients with postoperative recurrence than in those without.
  
  
  CONCLUSIONS
  Our study suggests that serum angiopoietin-2 is a useful clinical marker for detecting NSCLC with distant metastasis and is of potential prognostic value.
authors.affiliation: Department of Pulmonary and Critical Care Medicine, Ajou University School of Medicine, San 5, Wonchon-dong, Yeongtong-gu, Suwon, Gyeonggi-do 443-721, South Korea.
authors.forename: Joo Hun
authors.initials: JH
authors.lastname: Park
authors.forename: Kwang Joo
authors.initials: KJ
authors.lastname: Park
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: Seung Soo
authors.initials: SS
authors.lastname: Sheen
authors.forename: Keu Sung
authors.initials: KS
authors.lastname: Lee
authors.forename: Hyoung No
authors.initials: HN
authors.lastname: Lee
authors.forename: Yoon Jung
authors.initials: YJ
authors.lastname: Oh
authors.forename: Sung Chul
authors.initials: SC
authors.lastname: Hwang
mesh_terms: D000368:Aged; D042702:Angiopoietin-2 / Q000097:blood* / Q000235:genetics; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000175:diagnosis; D018288:Carcinoma, Small Cell / Q000097:blood* / Q000175:diagnosis; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008175:Lung Neoplasms / Q000097:blood* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
chemical_list: D042702:Angiopoietin-2; D042461:Vascular Endothelial Growth Factor A