Increased expression of nucleophosmin is associated with the pathophysiology of chronic rhinosinusitis with nasal polyposis

Abstract Objective Nucleophosmin (NPM1) has been suggested to be involved in the pathophysiologic mechanism of inflammatory disorders. We measured the expression level of NPM1 in nasal polyp (NP) tissues of patients with chronic rhinosinusitis with nasal polyposis (CRSwNP). We also assessed the correlation between NPM1 expression and other parameters such as eosinophilic infiltration, inflammatory cytokines, and clinical indicators such as Lund-Mackay computed tomography (CT) score. Methods Thirty patients with CRSwNP were included. We performed pre-operative CT scan to determine Lund-Mackay CT scores. During endoscopic sinus surgery, we harvested NP tissues from patients with CRSwNP. We performed Sirius red staining to evaluate eosinophilia and conducted immunohistochemical staining for NPM1 and real-time PCR for cytokines including interleukin (IL)-5, IL-17A, and IL-32. Results The mRNA expression of NPM1 was significantly up-regulated in eosinophilic NP tissues (RQ 0.58 ± 0.06), compared to non-eosinophilic NP tissues (RQ 0.38 ± 0.08, p  Conclusion Expression of NPM1 was significantly increased in eosinophilic NP tissues from patients with CRSwNP. We observed an association between NPM1 expression and various pro-inflammatory cytokines such as IL-5, IL-17, and IL-32 and eosinophilic infiltration, which is thought to contribute to the pathophysiology of NP.