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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Blotting, Western, Bronchi, Cells, Cultured, Epithelial Cells, Female, Glucocorticoids, Humans, Immunoenzyme Techniques, In Vitro Techniques, Male, Middle Aged, Mitogen-Activated Protein Kinase 1, Nasal Polyps, Occludin, Prednisone, Reverse Transcriptase Polymerase Chain Reaction, Up-Regulation.
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Does corticosteroid regulate epithelial occludin expression in nasal polyps through a MKP-1-dependent pathway? Context: To evaluate the regulatory effect of corticosteroid on occludin expression in polyp tissues of chronic rhinosinusitis with nasal polyps (CRSwNP) patients and in vitro. Twenty CRSwNP patients were enrolled and subjected to prednisone (30 mg/day for 14 days). The expression of occludin in polyp tissues was examined before and after treatment using immunohistochemical staining and quantitative reverse transcription polymerase chain reaction. Moreover, the expression of occludin in polyp-derived epithelial cells (PECs) and human bronchial epithelial cells (BECs) was examined using Western blot analysis in the presence of corticosteroid and/or MKP-1 siRNA, respectively. mRNA and protein expression of occludin in polyp tissues was significantly upregulated after prednisone administration (p < 0.05). Corticosteroids significantly increased MKP-1 and occludin expression in cultured PECs (p < 0.05), and MKP-1 siRNA significantly decreased occludin expression in cultured BECs (p < 0.05).
assistant
Our findings suggest that corticosteroid can promote epithelial occludin expression in nasal polyps through a MKP-1-dependent pathway. Final Decision: yes