title: Microarray analysis of gene expression in fibrovascular membranes excised from patients with proliferative diabetic retinopathy.
abstract: OBJECTIVE
  We determined the profile of genes expressed in fibrovascular membranes (FVMs).
  
  
  METHODS
  Six FVMs were surgically removed from patients with proliferative diabetic retinopathy (PDR) during pars plana vitrectomy with membrane peeling. The FVMs were classified into three active FVMs or three inactive FVMs according to the presence or absence of neovascularization (NV) in the membranes. Total RNA was isolated from the six FVMs and also from three normal human retinas. The DNA microarray analysis was performed to compare the genes expressed in the FVMs to those in normal human retinas, and also between active and inactive FVMs. Ingenuity pathway analysis (IPA) was used to determine the key biological networks related to the genes that were significantly altered. Quantitative RT-PCR and immunohistochemistry were performed to validate the microarray analyses.
  
  
  RESULTS
  There were 87 genes expressed at significantly higher levels in FVMs than in normal human retinas. Functional classification of these genes showed that the most clustered genes were those related to extracellular matrix formation. The top biological network generated by the IPA was cellular assembly and organization involving nodes of genes related to extracellular matrix formation. These networks included the collagen family and matricellular proteins, THBS2, POSTN, and TNC. There were 91 genes significantly upregulated in active FVMs, and the most clustered functional category was angiogenesis. In contrast, 89 genes were significantly upregulated in inactive FVMs, and the most clustered functional category was metabolism. The IPA revealed that the top biological network related to the genes that were significantly altered in this comparison was cell-to-cell signaling, and interactions involving the PDGF and TGFβ families. The results of quantitative RT-PCR analyses and immunohistochemistry for several selected molecules were in good agreement with the microarray data.
  
  
  CONCLUSIONS
  Our data indicate that extracellular matrix-related molecules such as POSTN, TNC, TGFβ, and angiogenic factors have important roles in promoting the development of FVMs associated with PDR.
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Keijiro
authors.initials: K
authors.lastname: Ishikawa
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Yoshida
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kobayashi
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yedi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Takahito
authors.initials: T
authors.lastname: Nakama
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Nakao
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan Fukuoka University Chikushi Hospital, Chikushino, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Sassa
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Oshima
authors.affiliation: Department of Medicine and Clinical Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Niiro
authors.affiliation: Department of Medicine and Clinical Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Akashi
authors.affiliation: Fukuoka University Chikushi Hospital, Chikushino, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kono
authors.affiliation: Department of Ophthalmology, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Ishibashi
mesh_terms: D003930:Diabetic Retinopathy / Q000235:genetics* / Q000378:metabolism / Q000601:surgery; D005136:Eye Proteins / Q000096:biosynthesis / Q000235:genetics*; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D046228:Microarray Analysis; D008875:Middle Aged; D012313:RNA / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014821:Vitrectomy
chemical_list: D005136:Eye Proteins; D012313:RNA
keywords: VEGF; angiogenesis; fibrosis; microarray; proliferative vitreoretinal disease