title: Association of angiopoietin-2, C-reactive protein and markers of obesity and insulin resistance with survival outcome in colorectal cancer.
abstract: BACKGROUND
  This study investigated the relationship of obesity, insulin resistance, inflammation and angiogenesis with cancer progression and survival in a colorectal cancer cohort.
  
  
  METHODS
  Clinical and pathological data, along with anthropometric and follow-up data, were collected from 344 consecutive colorectal cancer patients. Serum samples at diagnosis were analysed by immunoassay for adiponectin, C-reactive protein (CRP), vascular endothelial growth factor-A (VEGF-A), angiopoietin-2 (Ang-2), insulin-like growth factor-1 (IGF-1), insulin and C-peptide.
  
  
  RESULTS
  Serum Ang-2 and VEGF-A levels increased with tumour T stage (P=0.007 and P=0.025, respectively) and N stage (P=0.02 and P=0.03, respectively), and correlated with CRP levels (r=0.43, P<0.001 and r=0.23, P<0.001, respectively). Angiopoietin-2 correlated with C-peptide (r=0.14, P=0.007) and VEGF-A with IGF-1 in males (r=0.25, P=0.001). Kaplan-Meier analysis showed that patients with high serum levels of CRP and Ang-2 had significantly reduced survival (both P≤0.001). After adjusting for tumour stage and age, Ang-2 remained a significant predictor of survival. The CRP levels were inversely associated with survival in American Joint Committee on Cancer stage II patients (P=0.038), suggesting that CRP could be used to support treatment decisions in this subgroup. Serum markers and anthropometric measures of obesity correlated with each other, but not with survival.
  
  
  CONCLUSIONS
  Our study supports the concept that obesity-related inflammation, rather than obesity itself, is associated with colorectal cancer progression and survival. The study confirms serum Ang-2 as a predictive marker for outcome of colorectal cancer.
authors.affiliation: Angiogenesis and Cancer Research Group, Department of Pathology, University of Otago Christchurch, PO Box 4345, Christchurch 8140, New Zealand.
authors.forename: E
authors.initials: E
authors.lastname: Volkova
authors.forename: J A
authors.initials: JA
authors.lastname: Willis
authors.forename: J E
authors.initials: JE
authors.lastname: Wells
authors.forename: B A
authors.initials: BA
authors.lastname: Robinson
authors.forename: G U
authors.initials: GU
authors.lastname: Dachs
authors.forename: M J
authors.initials: MJ
authors.lastname: Currie
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000401:mortality* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D042702:Angiopoietin-2 / Q000097:blood*; D015415:Biomarkers / Q000378:metabolism*; D015992:Body Mass Index; D002096:C-Peptide / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D015179:Colorectal Neoplasms / Q000097:blood / Q000401:mortality* / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood*; D011446:Prospective Studies; D015996:Survival Rate; D016896:Treatment Outcome; D042461:Vascular Endothelial Growth Factor A / Q000097:blood
chemical_list: D042702:Angiopoietin-2; D015415:Biomarkers; D002096:C-Peptide; D007328:Insulin; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D007334:Insulin-Like Growth Factor I; D002097:C-Reactive Protein