AIM: To evaluate the effects of NS-398, a cyclooxygenase-2 (COX-2) inhibitor, on the proliferation and apoptosis of HepG2 cells. METHODS: The effects of NS-398 on the proliferation of HepG2 cells were evaluated by MTT...AIM: To evaluate the effects of NS-398, a cyclooxygenase-2 (COX-2) inhibitor, on the proliferation and apoptosis of HepG2 cells. METHODS: The effects of NS-398 on the proliferation of HepG2 cells were evaluated by MTT. DNA fragmentation gel analysis was used to analyze the apoptotic cells. DNA ploidy and apoptotic cell percentage were calculated by flow cytornetry. The expression of COX-2 and Bcl-2 mRNA was identified by competitive RT-PCR. Furthermore, expression level of Bcl-2 was detected using Western blot in HepG2 after treated with NS-398. RESULTS: NS-398 inhibited cell proliferation and induced apoptosis of HepG2 cells in a concentration-dependent manner. DNA ploidy analysis showed that S phase cells were significantly decreased with increase of NS-398 concentration. The quiescent GO/G1 phase was accumulated with decrease of Bcl-2 mRNA. Whereas NS-398 had no effect on the expression of COX-2 mRNA, and no correlations were found between COX-2 mRNA and HepG2 cell proliferation and apoptosis induced by NS-398 (r=0.056 and r=0.119, respectively). Bcl-2 protein level was inhibited after treated with NS-398. CONCLUSION: NS-398 significantly inhibits the proliferation and induces apoptosis of HepG2 cells. Mechanisms involved may be accumulation of quiescent GO/G1 phase and decrease of Bcl-2 expression.展开更多
BACKGROUND: Kang-Lai-Te (KLT) is extracted from the traditional Chinese herbal medicine Semen Coicis, which has been used in China as an effective clinical drug for over a thousand years. It contains numerous ingredie...BACKGROUND: Kang-Lai-Te (KLT) is extracted from the traditional Chinese herbal medicine Semen Coicis, which has been used in China as an effective clinical drug for over a thousand years. It contains numerous ingredients with anti-tumor effects. In our previous studies on transplanted hepatomas in rats, KLT could stop the cells in the G2+M stage of cell cycle and then reduce the number of cells entering the stage G0 and G1, but the mechanism of the anti-proliferative effect was unknown. In this experiment, we examined whether KLT inhibits HepG2 cell growth, if so, tried to explore its mechanism. METHODS: KLT at different concentrations was used for the treatment of hepatocellular carcinoma cells in vitro, respectively. The proliferation inhibitory rate was evaluated by MTT assay, induction of cell apoptosis rate and the protein levels of Fas and Fas ligand (FasL) were determined by flow cytometry (FCM), and the expression of Fas and FasL mRNA was detected by real-time fluorescent quantitative RT-PCR. RESULTS: KLT produced an obvious time and dose-dependent inhibitory effect on HepG2 cells, and marked apoptosis was detected by FCM The protein of Fas increased by 11.01%, 18.71%, 28.71% and 37.15%; the protein of FasL increased by 1.49%, 1.91%, 3.27% and 3.38% in comparison with the control (P<0.05). Real-time fluorescent quantitative RT-PCR showed that treating HepG2 cells with KLT caused the upregulation of Fas and FasL mRNA. CONCLUSION: KLT inhibits HepG2 growth by inducing apoptosis, which may be mediated through activation of the Fas/FasL pathway. (Hepatobiliary Pancreat Dis Int 2009; 8: 267-272)展开更多
文摘AIM: To evaluate the effects of NS-398, a cyclooxygenase-2 (COX-2) inhibitor, on the proliferation and apoptosis of HepG2 cells. METHODS: The effects of NS-398 on the proliferation of HepG2 cells were evaluated by MTT. DNA fragmentation gel analysis was used to analyze the apoptotic cells. DNA ploidy and apoptotic cell percentage were calculated by flow cytornetry. The expression of COX-2 and Bcl-2 mRNA was identified by competitive RT-PCR. Furthermore, expression level of Bcl-2 was detected using Western blot in HepG2 after treated with NS-398. RESULTS: NS-398 inhibited cell proliferation and induced apoptosis of HepG2 cells in a concentration-dependent manner. DNA ploidy analysis showed that S phase cells were significantly decreased with increase of NS-398 concentration. The quiescent GO/G1 phase was accumulated with decrease of Bcl-2 mRNA. Whereas NS-398 had no effect on the expression of COX-2 mRNA, and no correlations were found between COX-2 mRNA and HepG2 cell proliferation and apoptosis induced by NS-398 (r=0.056 and r=0.119, respectively). Bcl-2 protein level was inhibited after treated with NS-398. CONCLUSION: NS-398 significantly inhibits the proliferation and induces apoptosis of HepG2 cells. Mechanisms involved may be accumulation of quiescent GO/G1 phase and decrease of Bcl-2 expression.
基金supported by grants from the Distinguished Young Scholar Foundation of Shandong province,China(No.2006BS03039)the Science&Technology Key Project of Shandong province,China(No.2007G30002014).
文摘BACKGROUND: Kang-Lai-Te (KLT) is extracted from the traditional Chinese herbal medicine Semen Coicis, which has been used in China as an effective clinical drug for over a thousand years. It contains numerous ingredients with anti-tumor effects. In our previous studies on transplanted hepatomas in rats, KLT could stop the cells in the G2+M stage of cell cycle and then reduce the number of cells entering the stage G0 and G1, but the mechanism of the anti-proliferative effect was unknown. In this experiment, we examined whether KLT inhibits HepG2 cell growth, if so, tried to explore its mechanism. METHODS: KLT at different concentrations was used for the treatment of hepatocellular carcinoma cells in vitro, respectively. The proliferation inhibitory rate was evaluated by MTT assay, induction of cell apoptosis rate and the protein levels of Fas and Fas ligand (FasL) were determined by flow cytometry (FCM), and the expression of Fas and FasL mRNA was detected by real-time fluorescent quantitative RT-PCR. RESULTS: KLT produced an obvious time and dose-dependent inhibitory effect on HepG2 cells, and marked apoptosis was detected by FCM The protein of Fas increased by 11.01%, 18.71%, 28.71% and 37.15%; the protein of FasL increased by 1.49%, 1.91%, 3.27% and 3.38% in comparison with the control (P<0.05). Real-time fluorescent quantitative RT-PCR showed that treating HepG2 cells with KLT caused the upregulation of Fas and FasL mRNA. CONCLUSION: KLT inhibits HepG2 growth by inducing apoptosis, which may be mediated through activation of the Fas/FasL pathway. (Hepatobiliary Pancreat Dis Int 2009; 8: 267-272)