[Nuclear factor kappa B activity and cell viability of SMMC-7721 inhibited by mutated inhibitor kappa B alpha].

OBJECTIVE: To investigate the inhibition consequence of NF-kappaB activity and cell viability by transfecting mutated inhibitor kappa B alpha (mI(kappa)B(alpha)) into liver cancer cell line of SMMC-7721 cells. METHODS: The nucleic proteins of SMMC-7721 cells transfected with mI(kappa)B(alpha) plasmid and cells with empty pcDNA3 vector were used to determine not only the binding of the 32P-labelled kappaB probes by EMSA, but also the expression of NF-kappaB by western blot. Cell viability was also analyzed. RESULTS: NF-kappaB nuclear translocation was inhibited remarkably in SMMC-7721 cells transfected with mI(kappa)B(alpha) at 0, 24, 48 and 96 hours. Furthermore, NF-kappaB was not detected in the nucleic protein of mI(kappa)B(alpha) -transfected cells at the same intended time by western blot. Compared with that of control cells, the growth of SMMC-7721 cells transfected with mI(kappa)B(alpha) was suppressed evidently, especially on the second day, the cpm values of mI(kappa)B(alpha) -transfected cells, pcDNA3-transfected cells, and control cells were 5,092.63+/-541.41, 7,851.87+/-72.76, and 8,240.8+/-603.26 respectively (t = 14.29, P<0.01; t = 10.99, P<0.01). CONCLUSION: Stable expression of mI(kappa)B(alpha) in SMMC-7721 cells transfected with mI(kappa)B(alpha) plasmid inhibits NF-kappaB nuclear translocation, then suppresses the cell growth.