title: Thymoquinone chemosensitizes colon cancer cells through inhibition of NF-κB.
abstract: In the present study, the effects and molecular mechanisms of thymoquinone (TQ) on colon cancer cells were investigated. Cell viability was determined using a Cell Counting Kit-8 assay, and the results revealed that treatment with TQ significantly decreased cell viability in COLO205 and HCT116 cells in a dose-dependent manner. TQ treatment additionally sensitized COLO205 and HCT116 cells to cisplatin therapy in a concentration-dependent manner. To investigate the molecular mechanisms of TQ action, western blot analysis was used to determine the levels of phosphorylated p65 and nuclear factor-κB (NF-κB)-regulated gene products vascular endothelial growth factor (VEGF), c-Myc and B-cell lymphoma 2 (Bcl-2). The results indicated that TQ treatment significantly decreased the level of phosphorylated p65 in the nucleus, which indicated the inhibition of NF-κB activation by TQ treatment. Treatment with TQ also decreased the expression levels of VEGF, c-Myc and Bcl-2. In addition, the inhibition of NF-κB activation with a specific inhibitor, pyrrolidine dithiocarbamate, potentiated the induction of cell death and caused a chemosensitization effect of TQ in colon cancer cells. Overall, the results of the present study suggested that TQ induced cell death and chemosensitized colon cancer cells by inhibiting NF-κB signaling.
authors.affiliation: Department of Gastroenterology, The Affiliated Henan Provincial People's Hospital, Zhengzhou University, Zhengzhou, Henan 450003, P.R. China.
authors.forename: Lida
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Gastroenterology, The Affiliated Henan Provincial People's Hospital, Zhengzhou University, Zhengzhou, Henan 450003, P.R. China.
authors.forename: Yangqiu
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Department of Gastroenterology, The Affiliated Henan Provincial People's Hospital, Zhengzhou University, Zhengzhou, Henan 450003, P.R. China.
authors.forename: Yuxiu
authors.initials: Y
authors.lastname: Yang
keywords: cell death; chemosensitization; colon cancer; nuclear factor-κB; thymoquinone