The Effect of Nimesulide on the Expression of NF-κB, Bcl-2 and Bax in the Human Gastric Cancer SGC-7901 Cell Line

The effect of nimesulide on the expression of NF-kB, Bcl-2 and bax in the human gastric cancer SGC-7901 cell line

OBJECTIVE To investigate whether nimesulide can suppress tumor growth and induce apoptosis in SGC-7901 gastric cancer cells and to explore the molecular mechanism involved. METHODS SGC-7901 cells were cultured in RPM1 1640 medium containing different concentrations of nimesulide (0, 12.5, 50, 100, 200, 400 μmol/L). The MTT assay, morphological observation, electron microscopy (EM), immunohistochemical analysis and Western blot analysis were employed to investigate the effects of nimesulide on the SGC-7901 cells and to explore possible related molecular mechanisms. RESULTS Nimesulide inhibited the growth of SGC-7901 cells and elicited typical apoptotic morphologic changes. Nimesulide also decreased NF-kB and Bcl-2 expression, but increased the level of the Bax protein. The positive rate of Bcl-2 protein expression at 0, 50, 100 and 200 μmol/L of nimesulide was 58.3±14.0%, 50.2±9.9%, 32.8±5.0% and 22.7±5.5% respectively based on immunohistochemical staining. The positive rate of Bax protein expression was 22.0±5.7%, 29.2±6.5%, 42.7±5.9% and 74.5±9.1% and the NF-kB expression was 74.2±10.9%, 61.8±7.6%, 36.7±10.9% and 17.5±12.3%, Significant differences were found between 0 μmol/L and 100 μmol/L and 200 μmol/L. Western blot analysis also showed that the expression of NF-kB was decreased. CONCLUSION Nimesulide suppresses tumor growth and induces apoptosis by inhibiting NF-kB expression, which may be related to the over-expression of Bax relative to Bcl-2 expression. This work was supported by the grant form the Natural Science Foundation of the Education Department of Jiangsu Province of China (No. 05KJD320234 and 01KJB320011).