Vascular endothelial growth factor and children featuring nasal polyps
Introduction
Chronic rhinosinusitis (CRS) is a common disorder amongst children [1]. The condition may be associated with the formation of nasal polyps, although nasal polyps are not so frequently found amongst children as amongst adults [2]. To the best of our knowledge, the exact etiological mechanism leading to the formation of nasal polyps appears to have remained largely obscure, however nasal polyps are believed, by many, to be a multifactorial disease [3], [4]. The histomorphological findings associated with nasal polyps typically include submucosal fibrosis with remarkable edema [2]. It would appear that developing a good understanding of the pathomechanisms of inflammation underlying the development of nasal polyps would seem to be crucial for further success as regards the treatment of such disease.
In recent years, several studies have drawn attention to the potential role for certain growth factors as regards the development of nasal polyps [5], [6], [7]. Vascular endothelial-cell growth factor (VEGF) appears to participate in a number of inflammatory processes by inducing plasma extravasation and angiogenesis [8]. The development of edema within nasal polyps is suggested, by some, to be caused by chronic and persistent inflammatory stimuli, thus it would appear imperative to determine the role VEGF plays as regards the development of CRS featuring nasal polyps versus CRS without nasal polyps.
The aim of this study is to demonstrate, immunohistochemically, the presence of VEGF within nasal polyps, and to compare the level of activity of VEGF for CRS patients featuring nasal polyps versus those CRS patients who do not suffer from nasal polyps.
Section snippets
Materials and methods
From January 1999 to December 2004 inclusively, 60 children (31 boys) afflicted with chronic rhinosinusitis were enrolled to receive endoscopic sinus surgery as part of this study. Thirty of the 60 children revealed CRS associated with nasal polyps and the other 30 children suffered from CRS with no evidence of nasal polyps, these latter individuals acting as study controls. Patient ages ranged from 11 to 16 years inclusively (mean, 13.6 years). All patients exhibited signs and symptoms of
Results
The mean number of VEGF-expressing cells per visual field as viewed under light microscopy (×400) for individuals from the CRS with nasal polyps group, and the corresponding mean number for individuals from the group featuring CRS without nasal polyps was, respectively, 20.8 ± 4.0 and 11.5 ± 3.4, Table 1. Using light microscopy (×400), the mean vascular count per visual field for individuals from the CRS with nasal polyps group, and for those deriving from the control group was, respectively, 10.5 ±
Discussion
The histomorphological features of nasal polyps and chronic rhinosinusitis have some features in common, both conditions revealing edema, and inflammatory-cell infiltration of nasosinal tissue and nasal-polyp tissue. Furthermore, nasal polyps typically reveal various degrees of tissue remodelling within epithelium, glands, connective tissue and also blood vessels [13]. Although numerous factors are reportedly involved in blood-vessel remodelling [14], [15], [16], one of them, VEGF, an agent
Conclusion
From the results of this study, the presence of VEGF-staining cells was extremely abundant within nasal-polyp tissue, and the MVD intense, as compared to the corresponding case for patients featuring sinusitis mucosa without nasal polyps. Further, the expression of VEGF within nasal polyps was significantly correlated with the development of nasal polyps. VEGF participates in the formation of nasal polyps amongst children suffering chronic rhinosinusitis by inducing plasma extravasation and
References (33)
- et al.
Histological analysis of nasal polyps in children
Int. J. Pediatr. Otorhinolaryngol.
(2001) - et al.
Vascular endothelial growth factor
J. Biol. Chem.
(1992) Sinusitis in children
N. Engl. J. Med.
(1992)- et al.
Allergic factors in nasal polyps
Otolaryngology (ROC)
(1997) - et al.
The role of bacterial infection of the maxillary sinus in nasal polyps
Clin. Otolaryngol.
(1989) - et al.
Insulinlike growth factor I immunoreactivity in nasal polyps
Arch. Otolaryngol. Head Neck Surg.
(1998) - et al.
Eosinophils in chronically inflamed human upper airway tissues express transforming growth factor B1 gene (TGFB1)
J. Clin. Invest.
(1992) - et al.
Expression of basic fibroblast growth factor in nasal polyps
Otolaryngol. Head Neck Surg.
(1998) - et al.
Vascular permeability/vascular endothelial growth factor in nasal polyps
Acta Otolaryngol. Suppl.
(2000) - et al.
Cystic fibrosis