The Role of NF-kappa B Signaling Pathway in TNF-α-induced Gastric Cancer Cell Apoptosis / 中国医科大学学报

ABSTRACT

Objective To investigate the role of nuclear factor kappa-B（NF-κB）signaling pathway in tumor necrosis factor α（TNF-α）-induced apoptosis in gastric cancer cells.Methods Human gastric cancer cell line SGC7901 was treated with TNF-α for 24 hours.MTT assay,flowcytometry and Western blot was used to detect the cell viability and apoptosis.Transient transfection was performed by using Lipofectamine 2000 reagent.The cells of experimental group and control group were respectively transfected with mutant IκB cDNA and vectors.Results Under the treatment of 100,1 000 or 10 000 U/ml TNF-α,the cell viability of SGC7901 cells was（99.2±0.6）%,（92.0±2.7）% and（97.9±2.2）%,respectively.Further study showed that TNF-α engagement led to rapid activation of NF-κB signaling pathway.Blockage of TNF-α-induced NF-κB activation by transient transfection with a mutant IκB enhanced the sensitivity of cells towards TNF-α-induced apoptosis.Conclusion In human gastric cancer cells,activation of NF-κB signaling pathway by TNF-α might be responsible for the resistance to TNF-α-induced apoptosis.Blockage of NF-κB significantly enhanced the apoptosis induced by TNF-α.