title: Effects of bevacizumab on apoptosis, Na+ -K+ -adenosine triphosphatase and zonula occludens 1 expression on cultured corneal endothelial cells.
abstract: BACKGROUND
  This laboratory study was undertaken to investigate the influence of bevacizumab on apoptosis, Na(+)-K(+)-adenosine triphosphatase (Na(+)-K(+)-ATPase) and zonula occludens 1 (ZO-1) expression on cultured human corneal endothelial cells (HCECs).
  
  
  METHODS
  Annexin V binding combined with propidium iodide (PI) costaining was used to distinguish viable, early and late apoptotic cells. Immunolocalization of ZO-1 and Na(+)-K(+)-ATPase was performed to analyze intercellular cell integrity after exposure to 5.0 mg/ml bevacizumab for 24 h.
  
  
  RESULTS
  No significant induction of apoptosis or necrosis was seen in HCECs after exposure to 5.0 mg/ml bevacizumab (p = 0.689, p = 0.516, respectively). The mean number of annexin-V-FITC- and PI-positive cells did not change significantly. Additionally, no significant changes in expression were detectable, neither for ZO-1 nor for Na(+)-K(+)-ATPase in comparison with the control. For ZO-1, 70.0% of the cells stained intensely, 24.7% stained moderately, and 5.3% stained weakly in the control group. After exposure to 5.0 mg bevacizumab, only minor changes were observable: 68.8% stained intensely, 25.4% moderately and 5.8% weakly (p = 0.524). For Na(+)-K(+)-ATPase, 19.3% of the cells stained intensely, 59.4% moderately, and 21.3% weakly in the control group. After exposure to 5.0 mg bevacizumab, again only minor changes were observable in the expression pattern: 18.2% stained intensely, 60.3% moderately and 21.5% weakly. The changes were not significant compared with the control (p = 0.492).
  
  
  CONCLUSIONS
  Bevacizumab, at concentrations used clinically, did not induce apoptosis or necrosis in HCECs in vitro. Additionally, no alteration of ZO-1 or Na(+)/K(+)-ATPase expression was detected after exposure to 5.0 mg/ml bevacizumab for 24 h.
authors.affiliation: Department of Ophthalmology, Eberhard-Karl University, Tuebingen, Germany. Efdal.Yoeruek @ med.uni-tuebingen.de
authors.forename: Efdal
authors.initials: E
authors.lastname: Yoeruek
authors.forename: Olcay
authors.initials: O
authors.lastname: Tatar
authors.forename: Martin S
authors.initials: MS
authors.lastname: Spitzer
authors.forename: Oguzhan
authors.initials: O
authors.lastname: Saygili
authors.forename: Tilo
authors.initials: T
authors.lastname: Biedermann
authors.forename: Karl U
authors.initials: KU
authors.lastname: Bartz-Schmidt
authors.forename: Sebastian
authors.initials: S
authors.lastname: Thaler
authors.forename: Peter
authors.initials: P
authors.lastname: Szurman
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D017304:Annexin A5 / Q000378:metabolism; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D061067:Antibodies, Monoclonal, Humanized; D017209:Apoptosis / Q000187:drug effects*; D000068258:Bevacizumab; D002478:Cells, Cultured; D004728:Endothelium, Corneal / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D010750:Phosphoproteins / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors*; D062826:Zonula Occludens-1 Protein
chemical_list: D020533:Angiogenesis Inhibitors; D017304:Annexin A5; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D008565:Membrane Proteins; D010750:Phosphoproteins; C569042:TJP1 protein, human; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D062826:Zonula Occludens-1 Protein; D000068258:Bevacizumab; D000254:Sodium-Potassium-Exchanging ATPase