title: αA-crystallin gene CpG islands hypermethylation in nuclear cataract after pars plana vitrectomy.
abstract: OBJECTIVE
  To investigate the DNA methylation status of αA-crystallin gene in cataract secondary to pars plana vitrectomy.
  
  
  METHODS
  Anterior capsular membranes of 40 eyes of 40 patients with cataract secondary to vitrectomy were collected. Another 20 eyes of 20 patients who received pars plana vitrectomy and phacoemulsification in the primary procedure, were recruited as control. Methylation status of the CpG islands of αA-crystallin gene was analyzed by pyrosequencing. Expression of αA-crystallin was evaluated by real-time polymerase chain reaction and western blot.
  
  
  RESULTS
  In the post vitrectomy group, five patients with posterior subcapsular opacity and four patients with cortical opacity were excluded from further analysis. The remaining 31 patients with nuclear cataract were assigned into two groups according to tamponade types: 19 of octafluoropropane (C3F8) and 12 of silicone oil (SiO). The average nuclear color grading was elevated both in C3F8 and SiO groups after vitrectomy. Compared to the control group, hypermethylation of the CpG islands in the αA-crystallin gene promoter was found in both post vitrectomy groups, accompanied by significantly reduced αA-crystallin expression. No statistically significant differences were found between the C3F8 and SiO groups either for DNA methylation status or αA-crystallin expression.
  
  
  CONCLUSIONS
  CpG islands hypermethylation of αA-crystallin gene may be involved in nuclear cataract formation after pars plana vitrectomy.
authors: Department of Ophthalmology, Eye and ENT Hospital, Fudan University, 83 Fenyang Road, Shanghai, 200031, People's Republic of China.
authors: Xiang-Jia
authors: XJ
authors: Zhu
authors: Ke-Ke
authors: KK
authors: Zhang
authors: Peng
authors: P
authors: Zhou
authors: Chun-Hui
authors: CH
authors: Jiang
authors: Yi
authors: Y
authors: Lu
mesh_terms: D000328:Adult; D001483:Base Sequence; D015153:Blotting, Western; D058442:Capsule Opacification / Q000175:diagnosis / Q000209:etiology / Q000235:genetics*; D018899:CpG Islands / Q000235:genetics*; D003459:Crystallins / Q000235:genetics* / Q000378:metabolism; D019175:DNA Methylation / Q000235:genetics*; D058450:Endotamponade; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology; D005260:Female; D005466:Fluorocarbons; D006801:Humans; D007907:Lens Nucleus, Crystalline / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D060888:Real-Time Polymerase Chain Reaction; D012163:Retinal Detachment / Q000601:surgery; D012167:Retinal Perforations / Q000601:surgery; D012827:Silicone Oils; D014821:Vitrectomy / Q000009:adverse effects*
chemical_list: C511246:CRYAA protein, human; D003459:Crystallins; D005466:Fluorocarbons; D012827:Silicone Oils; C042852:perflutren