| Objective To explore the mechanism of Tumor Necrosis Factor-alpha(TNF-α) in the promotion of human gastric carcinoma cell invasion.Methods By using immunohistochemical technique ,to detect the activity of nuclear factor-kappa B (NF-kB) and the expression of urokinase type plasminogen activator(uPA) in SGC-7901 cells treated with different concentrations of TNF-α.The respective effect of TNF-αand Pyrrolidine dithiocarbamate(PDTC,an inhibitor of NF-kB ) on gastric cancer cell proliferation was detected with MTT. After pretreatment with PDTC and treated with different concentrations of TNF-α,the invasion of SGC-7901 cells was observed by Boyden migration assay.Results Immunohistochemistry assay showed that the activity of NF-Kb and the expression of uPA was significantly increased after TNF-αtreatment. TNF-a and PDTC did not affect the proliferation of SGC-7901 cells in limited concentrations, furthermore TNF-αtreatment resulted in increased invasions of SGC-7901 cells in dose-dependent and time-dependent manner( cell-number as TNF-αat 5,10,20ng/mL vs 0ng/mL: 84.33±3.786,108.33±6.110,121.330±4.163 vs63.330±4.933,F=126.282,P<0.001),while TNF-αinduced invasion of SGC-7901 cells was markedly inhibited by pretreatment with PDTC(cell number : 42.330±4.041 vs 63.330±4.933,F=126.282,P<0.05).Conclusions TNF-αpromotes the invasion of human gastric carcinoma cell,and the up-regulation of uPA and NF-kB activity is involved in this process. |
