title: Role of the VEGF ligand to receptor ratio in the progression of mismatch repair-proficient colorectal cancer.
abstract: BACKGROUND
  The VEGF family of ligands and receptors are intimately involved in tumor angiogenesis, lymphangiogenesis and metastasis. The evaluation of VEGF ligand/receptor ratios may provide a more profound understanding of the involvement of these proteins in colorectal tumour progression. The aim of this study was to elucidate the role of the VEGF ligand/receptor ratios on tumour progression and metastasis in patients with mismatch repair-proficient colorectal cancer.
  
  
  METHODS
  Immunohistochemistry for VEGF-A, VEGF-B, VEGF-C, VEGF-D, VEGFR1, VEGFR2 and VEGF3 was carried out on 387 mismatch repair-proficient colorectal cancers using a tissue microarray. Evaluation of immunoreactivity was performed semi-quantitatively and the ligand/receptor expression ratio was obtained.
  
  
  RESULTS
  An increased VEGF-A/VEGFR1 ratio, VEGF-A and VEGFR1 was linked to the presence of peritumoral lymphocytic inflammation at the invasive front (p = 0.032; p = 0.005; p = 0.032, respectively). VEGFR1 expression was related to poorer outcome in multivariable analysis with pT stage, pN stage, vascular invasion, and post-operative therapy. A higher ratio of VEGF-A/VEGFR2 was linked to advanced TNM stage (p = 0.005) while VEGF-A and VEGFR2 were elevated in tumours with an infiltrating tumour growth pattern (p = 0.006; p = 0.014; p = 0.006). No effect of VEGF-A/VEGFR2, VEGF-A or VEGFR2 on survival time was noted.
  
  
  CONCLUSIONS
  Our findings highlight an involvement of VEGF-A, VEGR1 and VEGFR2 in events occurring at the invasive tumour front and a potential prognostic role of VEGFR1 expression in mismatch repair-proficient colorectal cancers. The VEGF-A ligand to VEGFR1 or VEGFR2 ratio may represent an alternative evaluation system for identifying patients with poorer clinical outcome.
authors.affiliation: Institute of Pathology, University Hospital of Basel, Basel, Switzerland.
authors.forename: Manuela
authors.initials: M
authors.lastname: Eppenberger
authors.forename: Inti
authors.initials: I
authors.lastname: Zlobec
authors.forename: Daniel
authors.initials: D
authors.lastname: Baumhoer
authors.forename: Luigi
authors.initials: L
authors.lastname: Terracciano
authors.forename: Alessandro
authors.initials: A
authors.lastname: Lugli
mesh_terms: D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology*; D004260:DNA Repair; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007249:Inflammation; D008024:Ligands; D008297:Male; D009362:Neoplasm Metastasis; D020411:Oligonucleotide Array Sequence Analysis; D040262:Receptors, Vascular Endothelial Growth Factor / Q000378:metabolism; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A / Q000737:chemistry / Q000378:metabolism*
chemical_list: D008024:Ligands; D042461:Vascular Endothelial Growth Factor A; D040262:Receptors, Vascular Endothelial Growth Factor