Effect of Polyinosinic-Polycytidylic Acid on MUC5B Expression in Human Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Polyinosinic-polycytidylic acid (Poly I:C) is structurally similar to double-stranded RNA, and is known to induce various inflammatory mediators and to cause inflammatory reactions in airway epithelial cells. However, the effect of Poly I:C on secretion of mucins in human airway epithelial cells has been very rarely reported. In this study, the effect and brief signaling pathway of Poly I:C on the expression of mucin genes were investigated in human airway epithelial cells. MATERIALS AND METHOD: In mucin-producing human NCI-H292 airway epithelial cells and the primary cultures of normal human nasal epithelial cells, the effect and signaling pathway of Poly I:C on expression of mucin genes were investigated using reverse transcriptase-polymerase chain reaction, real-time PCR, enzyme immunoassay, and immunoblot analysis with specific inhibitors and small interfering RNA (siRNA) for mitogen-activated protein kinase (MAPK). RESULTS: Poly I:C induced the MUC5B expression, and activated the phosphorylation of ERK1/2 and p38 MAPK. U0126 (ERK1/2 MAPK inhibitor) and SB203580 (p38 MAPK inhibitor) inhibited the Poly I:C-induced MUC5B expression. In addition, the knockdown of ERK2 and p38 MAPK by siRNA significantly blocked the Poly I:C-induced MUC5B mRNA expression. CONCLUSION: Poly I:C induces the MUC5B expression via ERK2 and p38 MAPK signaling pathways in human airway epithelial cells. Therefore, Poly I:C may play a role in the regulation of mucus hypersecretion through MAPK signaling pathways in the human airway epithelial cells.

Effect of Multi-Walled Carbon Nanotubes on MUC5AC and MUC5B Expression in Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Multi-walled carbon nanotubes (MWCNT) are one of the most commonly used nanomaterials to date. Recent studies have demonstrated that MWCNT increase immune response and allergic inflammation in airway epithelial cells. However, the effects of MWCNT on mucin in human airway epithelial cells have not been reported. Therefore, in the present study, the effect of MWCNT on MUC16, MUC5AC, and MUC5B expressions were investigated in human airway epithelial cells. SUBJECTS AND METHOD: In mucin-producing human NCI-H292 airway epithelial cells and primary cultures of normal nasal epithelial cells, the effects of MWCNT on MUC16, MUC5AC, and MUC5B expression were analyzed by reverse transcription polymerase chain reaction, real-time polymerase chain reaction, and enzyme-linked immunosorbent assay. RESULTS: In human NCI-H292 airway epithelial cells, MWCNT significantly induced the expression MUC5AC and MUC5B mRNA and the production of MUC5AC and MUC5B protein. However, MWCNT did not induce the expression of MUC16 mRNA. In the primary cultures of normal nasal epithelial cells, MWCNT also induced the expression of MUC5AC and MUC5B mRNA and the production of MUC5AC and MUC5B proteins. CONCLUSION: The results of this study demonstrate that MWCNT induces MUC5AC and MUC5B expression in human airway epithelial cells. These findings provide important information about the biological role of MWCNT on mucus-secretion in human airway epithelial cells.

A Case of Enteropathy-Associated T-cell Lymphoma (EATL) Presenting Perforation after Chemotherapy for Primary Intestinal Lymphoma / 대한소화기내시경학회지

Intestinal T-cell lymphomas are fairly uncommon, and can sometimes be associated with enteropathy. Enteropathy-associated T-cell lymphoma (EATL) is commonly accompanied by a nonspecific mucosal ulceration, similar to that observed as a complication of celiac disease. The clinical course of EATL is quite unfavorable, and tends to have a generally poor prognosis. When a tumor invades the bowel wall and is treated with corticosteroids and chemotherapy, cell lysis with perforation often occurs, particularly in case of lymphoma. Recent data indicate that extensive resection may improve local control, and eliminate the risk of early mortality due to visceral perforation or hemorrhaging in unresected lesions during chemotherapy. Here, we report the case of a 51-year-old male who was diagnosed with primary gastrointestinal lymphoma after colonoscopy, and presented with EATL after emergent exploratory laparatomy. We also include a review of the literature regarding this uncommon entity.