Tumour VEGF/Non Tumour VEGF protein expression ratio as a biomarker for survival in colorectal cancer patients

AimsVascular endothelial growth factor (VEGF) over-expression is frequently considered as a marker of both, a poor prognosis and of an aggressive tumour phenotype. Colorectal carcinoma is still one of the most lethal malignancies. Thus, our purpose was to study the expression of VEGF in tumour tissue (VEGFt) and in the tissue surrounding tumours (VEGFnt) and analyse its correlation with clinico-pathological features and overall survival.MethodsThe study was designed to determine the concentration of vascular endothelial growth factor in tumour (n = 87) and non-tumour tissue (n = 230) obtained form the colorectal cancer patients. Accordingly, VEGF expression was studied in tissue homogenates by a quantitative sandwich ELISA method.ResultsThe study was performed on 317 colorectal samples from 87 colorectal cancer patients. VEGF expression was higher in the tumour than in the non-tumour area (P < 0.0005). In areas of 5–10 cm around the tumours, VEGF expression was higher than the expression obtained in proximal or distal edge of the resection. VEGFt expression was lower in patients with stage I than in patients with stage II, III, or IV. However, a shorter overall survival time was evident when the ratio obtained between VEGF expression in the tumour and mean VEGF expression in the non-tumour areas of the same patient (VEGFt/VEGFnt ratio) was ≤2 (P = 0.019).ConclusionsVEGF expression in colorectal cancer tissue was higher in tumour than in non-tumour areas. VEGFt expression was lower in initial clinical stages. Indeed, patients who presented a VEGFt/VEGFnt ratio >2 survived longer. This is the first report showing that the clinical outcome could be related to the VEGFnt over-expression in colorectal cancer patients.