Epithelial Cell Proliferation in Nasal Polyps Could Be Up‐Regulated by Platelet‐Derived Growth Factor

Abstract

The modifications of epithelial differentiation and proliferation observed in nasal polyps (NP) could be related to local secretion of growth factors, among which platelet-derived growth factor (PDGF) could play a key role. We therefore prospectively studied, by immunohistochemistry, proliferating cell nuclear antigen (PCNA, an S-phase cell marker), PDGF, and CD-68 (activated macrophages marker) expression in NP and inferior turbinate mucosa (NM) in 11 patients. Our data show that PCNA and PDGF expression are increased in NP epithelium, while CD-68 expression is increased in NP epithelium and lamina propria when compared to NM. Increased local PDGF secretion by numerous activated macrophages could therefore be involved in epithelial cell proliferation up-regulation in NP. PDGF could also be involved in the pathogenesis of NP via its connective tissue remodeling actions.

Role of Platelet-Derived Growth Factor in Airway Remodeling in Rhinosinusitis

“…21 It has also been reported that PDGF secretion by activated macrophages secreted up-regulated epithelial cell proliferation in nasal polyps. 22 However, the current report is the first to compare the protein and mRNA levels for PDGF-AA and -BB and PDGF-␣ and -␤ receptors in nasal mucosa from patients with AR, CRS without asthma, and CRS with asthma. PDGF-AA and -BB levels in nasal discharge were significantly increased in CRS with asthma, and mRNA levels for PDGF-AA and -BB were also significantly higher in nasal mucosa and polyps in CRS with asthma.…”

Overexpression of Hepatocyte Growth Factor and Its Receptor c-Met in Nasal Polyps

“…Although the etiology of nasal polyps is still unknown, several pathological studies [4][5][6][7] have addressed the key mechanisms leading to cellular proliferation, such as epithelial cell proliferation and angiogenesis, with the results suggesting that growth factors produced by inflammatory cells could affect cell proliferation. In those studies, insulinlike growth factor I, keratinocyte growth factor, and vascular endothelial growth factor were detected in nasal polyps and were implicated in the pathogenesis of disease.…”

Expression analysis of VEGFA, FGF2, TGFβ1, EGF and IGF1 in human nasal polyposis

“…Polypeptide growth factors have been shown to stimulate cell growth in various in vitro and in vivo systems. It has been reported that some growth factors, including TGFß, platelet-derived growth factor, insulin-like growth factor 1 (IGF1) and basic fibroblastic growth factor (bFGF), may contribute to cellular proliferation in NPs (11)(12)(13), thus no real-time RT-PCR experiments have been conducted for the verification of their results. RT-PCR is an established technique for quantifying mRNA expression in biological samples.…”