title: Effects of Bevacizumab on Bcl-2 Expression and Apoptosis in Retinal Pigment Epithelial Cells under Oxidative Stress.
abstract: OBJECTIVE
  To evaluate the effects of bevacizumab on expression of B-cell leukemia/lymphoma (Bcl)-2 and apoptosis in retinal pigment epithelial (RPE) cells under oxidative stress conditions.
  
  
  METHODS
  RPE cells were treated with H(2)O(2) (0, 100, 200, 300, and 400 µM) and bevacizumab at or above the doses normally used in clinical practice (0, 0.33, 0.67, 1.33, and 2.67 mg/mL). Cell apoptosis was measured using flow cytometry with annexin V-fluorescein isothiocyanate. The expression of Bcl-2 mRNA was determined using reverse transcription polymerase chain reaction.
  
  
  RESULTS
  Under low oxidative stress conditions (H(2)O(2) 100 µM), cell apoptosis was not significantly different at any concentration of bevacizumab, but Bcl-2 mRNA expression decreased with increasing concentration of bevacizumab (0.33, 0.67, 1.33, and 2.67 mg/mL). Under moderate oxidative stress conditions (H(2)O(2) 200 µM), Bcl-2 mRNA expression decreased with increasing concentration of bevacizumab (0.33, 0.67, 1.33, and 2.67 mg/mL), but cell apoptosis increased only at 2.67 mg/mL of bevacizumab. Under high oxidative stress (300 µM) conditions, cell apoptosis increased at high concentrations of bevacizumab (1.33 and 2.67 mg/mL), but it did not correlate with Bcl-2 expression.
  
  
  CONCLUSIONS
  Withdrawal of vascular endothelial growth factor can lead to RPE cell apoptosis and influences the expression of anti-apoptotic genes such as Bcl-2 under oxidative stress conditions. Since oxidative stress levels of each patient are unknown, repeated injections of intravitreal bevacizumab, as in eyes with age-related macular degeneration, might influence RPE cell survival.
authors.affiliation: Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, Korea.
authors.forename: Sukjin
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, Korea.
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, Korea.
authors.forename: Na Rae
authors.initials: NR
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology and Inha Vision Science Laboratory, Inha University School of Medicine, Incheon, Korea.
authors.forename: Hee Seung
authors.initials: HS
authors.lastname: Chin
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D000068258:Bevacizumab / Q000494:pharmacology*; D002460:Cell Line; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D055213:Retinal Pigment Epithelium / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors
chemical_list: D020533:Angiogenesis Inhibitors; C000595707:BCL2 protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab; D006861:Hydrogen Peroxide
keywords: Apoptosis; Bcl-2; Bevacizumab; Retinal pigment epithelial cell