Abstract
Purpose: :
Pterygium is a proliferative, inflammatory and invasive ocular surface disease. Epidemiologic studies have implicated environmental factors such as ultraviolet light, chronic irritation, and inflammation as causative factors. Furthermore, other hypotheses suggested that growth factors may be involved directly or indirectly in the pathogenesis of pterygium. Vascular endothelial growth factor (VEGF) is known to participate in tumour vascularization and the isoform 165 is the predominant form of the complex VEGF family. Our aim was to study VEGF expression in human pterygium and normal conjunctiva tissues.
Methods: :
Specimens of pterygia (n=8) and normal conjunctiva (n=8) were obtained from patients after written informed consent. Tissue was fixed in paraformaldehyde and embedded in paraffin. Tissue sections were used for immunohistochemical stains with anti-VEGF antibody. Real Time quantitative transcriptase polymerase chain reaction (qRT-PCR) techniques were used to analyze the VEGF 165 gene expression.
Results: :
Increased VEGF expression was observed in the pterygium tissue compared with the normal conjunctiva. In the normal conjunctiva the greatest expression of VEGF was observed in the area closest to the basal epithelial, while in the pterygium tissue the staining was observed throughout the subepithelial connective tissue.Levels of mRNA-VEGF165 were significantly higher in pterygium than in conjunctives, showing double expression in pterygium tissues
Conclusions: :
VEGF overexpression in human pterygium suggests that this angiogenic factor might play a main active role in pterygium pathogenesis, and the chance of the use of VEGF inhibitors in the therapy for this disease.
Keywords: pterygium • vascular endothelial growth factor • cornea: epithelium