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
Objective: We studied the inhibitory effect of human cholangiocarcinoma line (QBC939) treated by selective cyclooxygenase-2 (COX-2) inhibitor NS-398 and provided the theoretical foundation for the clinical practi...Objective: We studied the inhibitory effect of human cholangiocarcinoma line (QBC939) treated by selective cyclooxygenase-2 (COX-2) inhibitor NS-398 and provided the theoretical foundation for the clinical practice. Methods: Selec- tive COX-2 inhibitor NS-398 on the growth suppression was evaluated by MTT method. The apoptotic rate was quantified and cell cycle by flow cytometry (FCM). Invasive ability was detected by Transwell. The expression of vascular endothelial growth factor (VEGF) and COX-2 in cholangiocarcinoma line was determined by enzyme-linked immunosorbent assay (ELISA). Results: NS-398 could be time-dose dependently inhibited the growth, induced apoptosis, invasived ability, S phase was inhibited, down-regulate the expression of VEGF and COX-2 in cholangiocarcinoma line (QBC939). Conclusion: NS398 can inhibit proliferation of cholangiocarcinoma cell line QBC939 and inhibit the invasive ability and induce its apoptosis in vitro, which may contributed to the COX-2 dependent pathway to reduce the release of VEGF.展开更多
Objective: To investigate the expression of cyclooxygenase -2 (COX-2) in hepatocellular carcinoma cell lines and to explore the effect of NS-398, a selective inhibitor for COX-2, on HepG-2 cell line. Methods: lmmu...Objective: To investigate the expression of cyclooxygenase -2 (COX-2) in hepatocellular carcinoma cell lines and to explore the effect of NS-398, a selective inhibitor for COX-2, on HepG-2 cell line. Methods: lmmunohistochemistry and RT-PCR were used to investigate COX-2 expression in 6 HCC cell lines. MTT and Flowcytometry were used to evaluate the effect of the selective inhibitor of COX-2, NS-398, on HepG-2 cell lines. Results: All six HCC cell lines showed COX-2 expression at protein level. Five out of 6 cell lines showed COX-2 expression at mRNA level. NS-398 could suppress the growth of HepG-2 cell line, in a time and dose dependant manner. Conclusion: NS-398, a selective inhibitor of COX-2, showed inhibition effect on HepG-2 HCC cell line. The efficacy of inhibition was time and dose dependent, providing a new evidence for chemoprovention of hepatocellular carcinorma with COX-2 selective inhibitors.展开更多
AIM: To study the effect of NS-398, a selective cydooxygenase 2 (COX-2) inhibitor, on invasion of colon cancer cell line HT-29 in vitro and to explore its mechanisms. METHODS: Invasive behaviors of the malignant colon...AIM: To study the effect of NS-398, a selective cydooxygenase 2 (COX-2) inhibitor, on invasion of colon cancer cell line HT-29 in vitro and to explore its mechanisms. METHODS: Invasive behaviors of the malignant colon cancer cell line HT-29 were investigated in this study. Expressions of COX-2 and CD44v6 in HT-29 cells were detected by flow cytometry. Cellular survival rate was determined by MTT assay. The invasive capacity was quantified by a modified Boyden chamber model. Alterations of cytoskeleton component F-actin were observed by confocal laser scanning microscope. RESULTS: Flow cytometry analysis showed that COX-2 was highly expressed in HT-29 cells. The invasive capability of HT-29 cells could be greatly inhibited by NS-398 at the experimental concentrations of 0.1,1.0 and 10 μmol/L with an inhibitory rate of 22.74%, 42.35% and 58.61% (P<0.01), respectively. MTT assay showed that NS-398 at the experimental concentrations had no significant influence on cellular viability, indicating that such anti-invasive effects had no relationship with cytotoxicity. F-actin was mainly distributed around nuclei forming annular structure in HT-29 cells. After exposure to NS-398 of 10 μmol/L, the annular structure around nuclei disappeared and the fluorescence intensity of F-actin decreased obviously. Treatment with NS-398 could down-regulate the expression of CD44v6 as well. CONCLUSION: NS-398 has anti-invasive effects on colon cancer HT-29 cells in vitro, which may be mediated by a novel mechanism of disruption of cytoskeleton. Down-regulation of CD44v6 expression may be related to alterations of cytoskeleton.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.
文摘Objective: We studied the inhibitory effect of human cholangiocarcinoma line (QBC939) treated by selective cyclooxygenase-2 (COX-2) inhibitor NS-398 and provided the theoretical foundation for the clinical practice. Methods: Selec- tive COX-2 inhibitor NS-398 on the growth suppression was evaluated by MTT method. The apoptotic rate was quantified and cell cycle by flow cytometry (FCM). Invasive ability was detected by Transwell. The expression of vascular endothelial growth factor (VEGF) and COX-2 in cholangiocarcinoma line was determined by enzyme-linked immunosorbent assay (ELISA). Results: NS-398 could be time-dose dependently inhibited the growth, induced apoptosis, invasived ability, S phase was inhibited, down-regulate the expression of VEGF and COX-2 in cholangiocarcinoma line (QBC939). Conclusion: NS398 can inhibit proliferation of cholangiocarcinoma cell line QBC939 and inhibit the invasive ability and induce its apoptosis in vitro, which may contributed to the COX-2 dependent pathway to reduce the release of VEGF.
文摘Objective: To investigate the expression of cyclooxygenase -2 (COX-2) in hepatocellular carcinoma cell lines and to explore the effect of NS-398, a selective inhibitor for COX-2, on HepG-2 cell line. Methods: lmmunohistochemistry and RT-PCR were used to investigate COX-2 expression in 6 HCC cell lines. MTT and Flowcytometry were used to evaluate the effect of the selective inhibitor of COX-2, NS-398, on HepG-2 cell lines. Results: All six HCC cell lines showed COX-2 expression at protein level. Five out of 6 cell lines showed COX-2 expression at mRNA level. NS-398 could suppress the growth of HepG-2 cell line, in a time and dose dependant manner. Conclusion: NS-398, a selective inhibitor of COX-2, showed inhibition effect on HepG-2 HCC cell line. The efficacy of inhibition was time and dose dependent, providing a new evidence for chemoprovention of hepatocellular carcinorma with COX-2 selective inhibitors.
文摘AIM: To study the effect of NS-398, a selective cydooxygenase 2 (COX-2) inhibitor, on invasion of colon cancer cell line HT-29 in vitro and to explore its mechanisms. METHODS: Invasive behaviors of the malignant colon cancer cell line HT-29 were investigated in this study. Expressions of COX-2 and CD44v6 in HT-29 cells were detected by flow cytometry. Cellular survival rate was determined by MTT assay. The invasive capacity was quantified by a modified Boyden chamber model. Alterations of cytoskeleton component F-actin were observed by confocal laser scanning microscope. RESULTS: Flow cytometry analysis showed that COX-2 was highly expressed in HT-29 cells. The invasive capability of HT-29 cells could be greatly inhibited by NS-398 at the experimental concentrations of 0.1,1.0 and 10 μmol/L with an inhibitory rate of 22.74%, 42.35% and 58.61% (P<0.01), respectively. MTT assay showed that NS-398 at the experimental concentrations had no significant influence on cellular viability, indicating that such anti-invasive effects had no relationship with cytotoxicity. F-actin was mainly distributed around nuclei forming annular structure in HT-29 cells. After exposure to NS-398 of 10 μmol/L, the annular structure around nuclei disappeared and the fluorescence intensity of F-actin decreased obviously. Treatment with NS-398 could down-regulate the expression of CD44v6 as well. CONCLUSION: NS-398 has anti-invasive effects on colon cancer HT-29 cells in vitro, which may be mediated by a novel mechanism of disruption of cytoskeleton. Down-regulation of CD44v6 expression may be related to alterations of cytoskeleton.