Protective effect and mechanism of rebamipide on NSAIDs associated small bowel injury.

PURPOSE: To investigate the protective effect and mechanism of rebamipide on NSAIDs associated intestinal injury. METHODS: Intestinal injury was induced in Sprague Dawley rats by intragastric administration of diclofenac with rebamipide intervention, and LPS and TAK-242 were given intraperitoneally respectively. The expression of TLR4/NF-κB and the related proteins in the intestinal mucosa were detected. 55 patients taking NSAIDs and diagnosed as NSAIDs associated small intestinal injury were recruited as NSAIDs group. Another 55 patients without NSAIDs and no obvious abnormality in the small bowel served as the control group. RESULTS: The macroscopic and histological scores of the small intestinal mucosa in the rebamipide pretreatment group were significantly lower compared to the diclofenac group (p < 0.01). The expressions of Tollip, ZO-1 and Claudin-1 in the diclofenac group were down-regulated compared with that in the control group, while they increased significantly in the rebamipide pretreatment group (p < 0.01). The expressions of TLR4/NF-κBp65, IL-1ß, IL-6, IL-8, and TNF-α significantly increased in the model group while they were down-regulated in the rebamipide pretreatment group (p < 0.05). Administration of LPS 1 h after diclofenac aggravated small intestinal damage, and increased expression of IL-1ß, IL-6, IL-8 and TNF-α. Administration of rebamipide did not effectively reverse intestinal injury induced by diclofenac and LPS. In contrast, pretreatment with TAK-242 significantly inhibited damage and prevented the increased expression of the cytokines. The expression of TLR4 and NF-κBp65 in the patients with NSAIDs associated intestinal injury was significantly higher than that in the control group (p < 0.01), while the expression of Tollip was decreased (p < 0.01). CONCLUSION: Rebamipide effectively alleviated intestinal mucosa injury by probably suppressing the TLR4/NF-κB signaling pathway and the decreasing of ZO-1 and Claudin-1 induced by diclofenac.

BCLAF1 promotes cell proliferation, invasion and drug-resistance though targeting lncRNA NEAT1 in hepatocellular carcinoma.

AIMS: In the present research, we aimed to investigate the effect of Bcl-2-associated transcription factor 1 (BCLAF1) on hepatocellular carcinoma and further explore the special molecular mechanism. MAIN METHODS: The expression of BCLAF1 was analyzed in tumor tissues and different hepatocellular cancer cell lines by real-time RT-PCR and Western blot. Cell proliferation and invasion was explored using MTT and Transwell assay respectively. In addition, luciferase reporter assay was performed to determine the binding activity of BCLAF1 and Nuclear enrichment-rich transcription factor 1 (NEAT1) promoter. Finally, the IC50 for 5-Fluorouracil (5-Fu) was measured by MTT assay, and Western blot was used to determine the expression of P-glycoprotein (P-gp) and multidrug resistance protein1 (MRP1). KEY FINDING: The result revealed that BCLAF1 was highly expressed in hepatocellular carcinoma tissues and cells. In addition, BCLAF1-siRNA inhibited the proliferation and invasion of hepatocellular carcinoma cells, and overexpression of BCLAF1 promoted proliferation and invasion. Furthermore, luciferase reporter assay demonstrated that BCLAF1 directly interact with lncNEAT1 promoter and improved NEAT1 expression, and BCLAF1 promoted proliferation and invasion through targeting lncRNA NEAT1. What's more, BCLAF1 promoted 5-Fu resistance and the expression of P-gp and MRP1 in hepatocellular carcinoma cells by targeting NEAT1. SIGNIFICANCE: The results of the present study suggested that BCLAF1 might be a new gene related to proliferation and drug-resistance of hepatocellular carcinoma. In the future, the search for a deep and reasonable mechanism for the role of BCLAF1 will help us to understand its function more comprehensively, and finally find a new method for the treatment of human cancer.