title: [Expression and regulation of tight junction protein Occludin in nasal polyps].
abstract: OBJECTIVE
  To evaluate the possible role of tight junction protein Occludin in nasal polyps.
  
  
  METHODS
  The expression of Claudin-1, Occludin and ZO-1 in nasal polyps (n = 20) and healthy uncinate mucosa (n = 15) were examined using immunohistochemical staining, real-time quantitative polymerase chain reaction (PCR) and Western blot analysis. The regulatory effects of proinflammatory cytokines (IFN-γ, IL-13, IL-17, TGF-β, TGF-α) on the expression of Occludin in cultured human nasal epithelial cells were investigated.
  
  
  RESULTS
  The immunohistochemical results showed that Claudin-1, Occludin and ZO-1 were detected both in the nasal polyp group and the control group. The expression sites were the cell membrane and cytoplasm of nasal mucosa epithelial cells. The mean optical density of Claudin-1, Occludin and ZO-1 were 0.187 ± 0.076,0.172 ± 0.109 and 0.098 ± 0.035 respectively in the nasal polyp group and were significantly lower than those in the control group (0.312 ± 0.101, 0.220 ± 0.069 and 0.233 ± 0.093 respectively), the differences were significant (t = 9.345, t = 3.301, t = 13.323, all P < 0.01).RT-PCR results showed that the relative expression of Occludin mRNA was 0.000 117 ± 0.000 035 in the nasal polyp group and was significantly lower than that in the control group(0.000 464 ± 0.000 134), and the difference was significant (Z = -5.0, P < 0.01) . There was no statistically significant difference in the relative expression of Claudin-1 and ZO-1 mRNA between the nasal polyp group and the control group (P > 0.05) . After the cultured human nasal epithelial cells were stimulated by IL-13, IL-17, IFN-γ and other proinflammatory cytokines, the relative expression of Occludin mRNA was 0.631 ± 0.039, 0.581 ± 0.029 and 0.648 ± 0.040, respectively. Compared with the unstimulated control group, the differences were statistically significant (t = 16.299, 24.669 and 14.995 respectively, all P < 0.05).Western blot analyse showed that the relative grayscale in the above proinflammatory cytokines stimulation groups was 0.650 ± 0.061,0.482 ± 0.106 and 0.536 ± 0.109, respectively. Compared with the unstimulated control group, the differences were statistically significant (t = 9.880, 8.442 and 7.310 respectively, all P < 0.05).
  
  
  CONCLUSIONS
  The reduced expression of Occludin might be involved in the pathogenesis of nasal polyps.
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
authors.forename: Jiebo
authors.initials: J
authors.lastname: Guo
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
authors.forename: Han
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
authors.forename: Kejun
authors.initials: K
authors.lastname: Zuo
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wei
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Shi
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
authors.forename: Huabin
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China. Email: entxgfess@163.com.
authors.forename: Geng
authors.initials: G
authors.lastname: Xu
mesh_terms: D062445:Claudin-1; D016207:Cytokines; D004847:Epithelial Cells; D006801:Humans; D018793:Interleukin-13; D020381:Interleukin-17; D009297:Nasal Mucosa; D009298:Nasal Polyps / Q000378:metabolism*; D062793:Occludin / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger; D019108:Tight Junctions / Q000378:metabolism*; D016211:Transforming Growth Factor alpha; D062826:Zonula Occludens-1 Protein
chemical_list: D062445:Claudin-1; D016207:Cytokines; D018793:Interleukin-13; D020381:Interleukin-17; D062793:Occludin; D012333:RNA, Messenger; D016211:Transforming Growth Factor alpha; D062826:Zonula Occludens-1 Protein