title: Regulation of Apoptosis by miR-122 in Pterygium via Targeting Bcl-w.
abstract: To identify the differently expressed micro (mi) RNAs in pterygium compared with normal conjunctiva and investigate the potential role of miRNAs in the pathogenesis of pterygium.
  
  
  
  With microRNA microarray and quantitative RT-PCR, we identified that microRNA-122 (miR-122) was significantly decreased in pterygium tissue. We detected the expression of Bcl-w, a predicted target of miR-122, in both pterygium and normal conjunctiva, as well as its correlation with the expression of miR-122. Pterygium epithelial cells were isolated and cultured, and transfected with miR-122 mimic or miR-122 inhibitor to change the miR-122 levels. The regulation of Bcl-w expression by miR-122 was examined with luciferase activity assay, quantitative (q) RT-PCR, and Western blot. The effect of the miR-122 on the apoptosis of cultured pterygium epithelial cells was investigated with TUNEL staining and caspase activity assay.
  
  
  
  We found the expression of Bcl-w, with an inverse correlation with the expression of miR-122, was significantly increased in pterygium, especially in the superficial layer of epithelium. In cultured pterygium epithelial cells, miR-122 could specifically combine with Bcl-w mRNA, and negatively regulated the expression of Bcl-w. Suppression of miR-122 could reduce apoptosis and caspase activity in pterygium epithelial cell treated with TNFα/cycloheximide (CHX), and this effect was abolished by inhibition of the expression of Bcl-w with specific siRNA.
  
  
  
  Decreased expression of miR-122 in pterygium might result in abnormal cell apoptosis via its regulation of the expression of Bcl-w, and subsequently contribute to the development of pterygium.
authors.affiliation: Department of Histology and Embryology, Guangzhou Medical University, Guangzhou, China.
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Cui
authors.affiliation: Department of Ophthalmology, Guangdong No.2 Provincial People's Hospital, Guangzhou, China 3Department of Ophthalmology, Guangzhou Red Cross Hospital, the fourth affiliated hospital of Jinan University, Guangzhou, China.
authors.forename: Hong-Yang
authors.initials: HY
authors.lastname: Li
authors.affiliation: Institute of Ophthalmology, School of Medicine, Jinan University, Guangzhou, China.
authors.forename: Zi-Xun
authors.initials: ZX
authors.lastname: Gao
authors.affiliation: Department of Ophthalmology, Guangzhou Red Cross Hospital, the fourth affiliated hospital of Jinan University, Guangzhou, China.
authors.forename: Na
authors.initials: N
authors.lastname: Liang
authors.affiliation: Department of Ophthalmology, Guangzhou Red Cross Hospital, the fourth affiliated hospital of Jinan University, Guangzhou, China.
authors.forename: Sheng-Sheng
authors.initials: SS
authors.lastname: Ma
authors.affiliation: Department of Ophthalmology, Guangzhou Red Cross Hospital, the fourth affiliated hospital of Jinan University, Guangzhou, China.
authors.forename: Fan-Jian
authors.initials: FJ
authors.lastname: Meng
authors.affiliation: Institute of Ophthalmology, School of Medicine, Jinan University, Guangzhou, China.
authors.forename: Zhi-Jie
authors.initials: ZJ
authors.lastname: Li
authors.affiliation: Institute of Ophthalmology, School of Medicine, Jinan University, Guangzhou, China 5Department of Public Health and Preventive Medicine, Jinan University, Guangzhou, China.
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Pan
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D017209:Apoptosis / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D016022:Case-Control Studies; D020169:Caspases / Q000378:metabolism; D002478:Cells, Cultured; D003228:Conjunctiva / Q000378:metabolism; D003513:Cycloheximide / Q000494:pharmacology; D015536:Down-Regulation / Q000502:physiology; D004847:Epithelial Cells / Q000378:metabolism; D006801:Humans; D035683:MicroRNAs / Q000378:metabolism / Q000502:physiology*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D011625:Pterygium / Q000209:etiology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D051017:Apoptosis Regulatory Proteins; C491073:BCL2L2 protein, human; C531907:MIRN122 microRNA, human; D035683:MicroRNAs; D011500:Protein Synthesis Inhibitors; D014409:Tumor Necrosis Factor-alpha; D003513:Cycloheximide; D020169:Caspases