title: Effect of NF-κB inhibitors on the chemotherapy-induced apoptosis of the colon cancer cell line HT-29.
abstract: This study aimed to investigate the impact of the combined use of the nuclear factor-κB (NF-κB) inhibitors pyrrolidine dithiocarbamate (PDTC), bortezomib or SN50, and the chemotherapy agents arsenic acid (As(2)O(3)), fluorouracil (5FU), oxaliplatin or paclitaxel on the growth and apoptosis of HT-29 cells. Cell morphology was observed using inverted microscopy, and cell viability and apoptosis were assessed using the MTT assay and flow cytometry, respectively. The activities of NF-κB were analyzed by western blotting and electrophoretic mobility shift assay (EMSA). Cell growth was significantly inhibited by As(2)O(3), oxaliplatin and paclitaxel in a time- and concentration-dependent manner (P<0.05), while 5FU inhibited cell growth in a time-dependent manner only (P<0.05). The growth inhibition rate and apoptosis induction ratio were increased following the combined treatment of the chemotherapy agent and NF-κB inhibitor. The expression of NF-κB p65 was upregulated when cells were treated with a chemotherapy drug, however it was downregulated following combined treatment or treatment with an NF-κB inhibitor alone. In conclusion, an NF-κB inhibitor combined with a chemotherapy drug effectively inhibited cell proliferation, induced cell apoptosis and inhibited NF-κB activity to enhance the chemotherapeutic sensitivity of HT-29 cells.
authors.affiliation: Department of Gastroenterology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086,  P.R. China.
authors.forename: Ting
authors.initials: T
authors.lastname: Liu
authors.forename: Dan
authors.initials: D
authors.lastname: Liu
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Ji-Tao
authors.initials: JT
authors.lastname: Song
authors.forename: Shan-Ling
authors.initials: SL
authors.lastname: Gao
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Li-Hong
authors.initials: LH
authors.lastname: Hu
authors.forename: Bing-Rong
authors.initials: BR
authors.lastname: Liu