The Effects Of Selective Somatostatin Receptor Agonists , Nimesulide On Human Hepatoma Cell

Objectives 1.To investigate the effects of selective somatostatin receptor (SSTR) agonists,selective COX-2 inhibitor (nimesulide) on proliferation,apoptosis and migration of human hepatoma cell (HepG2). 2.To examine whether SSTR agonists combined with nimesulide could enhance the effects on proliferation,apoptosis and migration HepG2. 3. To understand the influence of nimesulide on the expression of Smad4 in HepG2.Methods 1.Effects of SSTR agonists and nimesulide on proliferation,apoptosis and migration of HepG2 were assessed by MTS,The TdT-mediated dUTP nick end labelin assay (TUNEL) and transwell, respectively. 2.The influence of nimesulide on the expression of Smad4 in HepG2 was investigated by fluorescein isothiocyanate (FITC).Results1. None of four SSTR agonists influenced proliferation or apoptosis of HepG2. However, SSTR5 agonist (L-817,818) showed an obvious inbitory effect on migration when dosage was 1μg/ml, there was a statistical significance when the dosage reached to 5μg/ml (P<0.05).2. Nimesulide showed an obvious inbitory effect on proliferation and migration of HepG2, with an obvious dose-dependent manner, there was a statistical significance when the dosage was 100, 200, 400μmol/L and 200, 400μmol/L, respectively(P<0.05). Nimesulide could promote the apoptosis of HepG2, it had an obvious apoptosis signs compared with control group, like pyknosis, splitting, etc.3. The combination of SSTR agonists and nimesulide could not improve the inhibitory effect on proliferation and migration of HepG2, compared with control group. 4. The expression of Smad4 followed nimesulide was higher than control group.Conclusion1. SSTR agonists have no significant effects on proliferation and apoptosis of HepG2, SSTR5 agonist (L-817,818) shows an obvious inbitory effect on migration when the dosage is high.2. Nimesulide can suppress the proliferation and migration of HepG2, promote apoptosis of HepG2.3. The combination of SSTR agonists and nimesulide could not improve the inhibitory effect on proliferation and migration of HepG2.4. Nimesulide shows an anti-hepatic carcinoma by up-regulating the expression of Smad4.