Tauroursodeoxycholic acid attenuates colitis‐associated colon cancer by inhibiting nuclear factor kappaB signaling

• DOI: 10.1111/jgh.14526
• Publication Date: 2018-10-31T02:09:42Z
• Authors: Young Hoon Kim; Jee Hyun Kim; Byeong Gwan Kim; Kook Lae Lee; Ji Won Kim; Seong‐Joon Koh
• Keywords: Male; 0301 basic medicine; Colon; Interleukin-8; NF-kappa B; Apoptosis; Colitis; 3. Good health; Mice, Inbred C57BL; Taurochenodeoxycholic Acid; 03 medical and health sciences; Interleukin-1alpha; Tumor Cells, Cultured; Animals; Colorectal Neoplasms; Signal Transduction

AbstractBackground and AimInflammatory bowel diseases is associated with an increased risk for the development of colorectal cancer. However, the mechanism of immune signaling pathways linked to colitis‐associated cancer (CAC) has not been fully elucidated. Tauroursodeoxycholic acid (TUDCA) exhibits anti‐inflammatory and anti‐cancer activities. The aim of this study is to investigate the role of TUDCA in the pathogenesis of CAC.MethodsColitis‐associated cancer was induced in mice using azoxymethane and dextran sodium sulfate administration, and TUDCA's effect on tumor development was evaluated. HCT 116 and COLO 205 were treated with TUDCA or vehicle and then stimulated with tumor necrosis factor‐α (TNF‐α). Expression of interleukin (IL)‐8 was determined by real‐time reverse transcription‐polymerase chain reaction and enzyme‐linked immunosorbent assay, and IκBα phosphorylation and degradation was evaluated by immunoblot assay. The DNA‐binding activity of NF‐κB was assessed by electrophoretic mobility shift assay. Cell viability assay and real‐time reverse transcription‐polymerase chain reaction of bcl‐xL, MCL1, c‐FLIP‐L, and VEGF were performed.ResultsTauroursodeoxycholic acid significantly attenuated the development of CAC in mice. Exposure to TUDCA resulted in extensive epithelial apoptosis and reduced levels of phospho‐IκB kinase in the colon. In HCT 116 cells stimulated with TNF‐α, TUDCA significantly inhibited IL‐8 and IL‐1α expression and suppressed TNF‐α‐induced IκBα phosphorylation/degradation and DNA‐binding activity of NF‐κB. Furthermore, in both HCT 116 and COLO 205 cells, TUDCA reduced cell viability and downregulated the expression of bcl‐xL, MCL1, c‐FLIP‐L, and VEGF.ConclusionThese results demonstrated that TUDCA suppresses NF‐κB signaling and ameliorates colitis‐associated tumorigenesis, suggesting that TUDCA could be a potential treatment for CAC.