title: Expression of Endoglin and Vascular Endothelial Growth Factor as Prognostic Markers in Experimental Colorectal Cancer.
abstract: OBJECTIVE
  Endoglin (CD105) is a receptor for the transforming growth factor-beta 1 (TGFβ1) with crucial role in vascular development and angiogenesis. Additionally, vascular endothelial growth factor (VEGF) overexpression has been associated with advanced stage and poor survival for several cancer types. These molecules have been shown to be useful markers for identifying proliferating endothelium involved in tumor angiogenesis, especially in patients with cancer at risk of developing metastases. The aim of this study was to evaluate the relationship between VEGF and endoglin expression in an experimental model of colorectal cancer, as well as to investigate the effect of cyclooxygenase-2 (COX2) inhibitors on tumor development incidence.
  
  
  METHODS
  Colon cancer was induced with 1,2-dimethylhydrazine dihydrochloride (DMH). Celecoxib and diclofenac treatment was started simultaneously with DMH induction. Endoglin protein expression was performed using western blot analysis. VEGF plasma concentrations were measured by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  In histopathological evaluations, no pathological change was observed in control rats, while adenocarcinoma (62.5%), dysplasia (31.25%) and inflammation (6.25%) were detected in the group given DMH. In treatment groups, a marked decrease was observed in adenocarcinoma rate. Expression of endoglin protein was significantly elevated in the DMH group compared to controls (p<0.001). No statistically significant difference was noted between treatment groups and DMH group regarding endoglin expression but a decrease was detected in the celecoxib-treated groups.
  
  
  CONCLUSIONS
  It was confirmed by histopathology and western blotting that COX2 inhibitors, particularly celecoxib, decrease the rate of disease and slow-down progression of existing CRC. These data show that endoglin expression may have an important role in tumor angiogenesis and predict of tumor invasion.
authors.affiliation: Department of Medical Biochemistry, Firat University Faculty of Veterinary Medicine, Elazig, Turkey drnilhan@yahoo.com.
authors.forename: Nevin
authors.initials: N
authors.lastname: Ilhan
authors.affiliation: Department of Medical Biochemistry, Firat University Faculty of Veterinary Medicine, Elazig, Turkey.
authors.forename: Hilal
authors.initials: H
authors.lastname: Gungor
authors.affiliation: Department of Medical Biochemistry, Firat University Faculty of Veterinary Medicine, Elazig, Turkey.
authors.forename: H Fatih
authors.initials: HF
authors.lastname: Gul
authors.affiliation: Department of Pathology, Firat University Faculty of Veterinary Medicine, Elazig, Turkey.
authors.forename: Hatice
authors.initials: H
authors.lastname: Eroksuz
mesh_terms: D000230:Adenocarcinoma / Q000139:chemically induced / Q000235:genetics / Q000473:pathology; D000818:Animals; D014408:Biomarkers, Tumor / Q000096:biosynthesis* / Q000235:genetics; D000068579:Celecoxib / Q000008:administration & dosage; D015179:Colorectal Neoplasms / Q000139:chemically induced / Q000235:genetics* / Q000473:pathology; D052246:Cyclooxygenase 2 Inhibitors / Q000008:administration & dosage; D004008:Diclofenac / Q000008:administration & dosage; D000071063:Endoglin / Q000096:biosynthesis* / Q000235:genetics; D066246:ErbB Receptors / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007093:Imidazoles / Q000633:toxicity; D007249:Inflammation / Q000139:chemically induced / Q000235:genetics / Q000473:pathology; D009374:Neoplasms, Experimental / Q000139:chemically induced / Q000235:genetics* / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000235:genetics / Q000473:pathology; D011379:Prognosis; D051381:Rats; D053773:Transforming Growth Factor beta1 / Q000096:biosynthesis / Q000235:genetics; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; D052246:Cyclooxygenase 2 Inhibitors; D000071063:Endoglin; D007093:Imidazoles; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A; D004008:Diclofenac; C512478:EGFR protein, human; D066246:ErbB Receptors; D000068579:Celecoxib; C032654:1,2-dimethylimidazole
keywords: COX-2 inhibitors; Colorectal cancer; VEGF; angiogenesis; endoglin