BACKGROUND AND OBJECTIVE: Celecoxib can inhibit cell proliferation, regulate cell cycle and induce apoptosis, but the underlying mechanisms are still unclear. This study was to investigate the association between the NF-kappaB (kappaB) pathway and the apoptosis of breast cancer cell line MDA-MB-231 induced by celecoxib. METHODS: The expression of cyclo-oxygenase-2 (COX-2) mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR). Cell proliferation and cell cycle were detected by MTT and flow cytometry (FCM), respectively. The protein expressions of caspase-3 and p65 in MDA-MB-231 cells were detected by western blot. RESULTS: After incubation with different concentrations of celecoxib for 48 h, COX-2 mRNA expression in MDA-MB-231 cells was decreased in a dose-dependent manner compared with untreated cells (P<0.05). Proliferation of MDA-MB-231 cells was reduced drastically in a dose-and time-dependent manner after celecoxib treatment (P<0.05). Combination of prostaglandin E2 (PGE2) and celecoxib exerted similar inhibition effect to celecoxib alone on cell growth (P>0.05). High-dose celecoxib induced an increase in the percentage of G0/G1 phase cells accompanied by the change in DNA ploidy. The cellular caspase-3 level was enhanced whereas the p65 level was decreased in celecoxib-treated MDA-MB-231 cells after 24 h in comparison to those in the control cells. CONCLUSION: Celecoxib could inhibit MDA-MB-231 cell proliferation and promote cell apoptosis by down-regulating the NF-kappaB signaling pathway.
BACKGROUND AND OBJECTIVE:Celecoxib can inhibit cell proliferation, regulate cell cycle and induce apoptosis, but the underlying mechanisms are still unclear. This study was to investigate the association between the NF-kappaB (kappaB) pathway and the apoptosis of breast cancer cell line MDA-MB-231 induced by celecoxib. METHODS: The expression of cyclo-oxygenase-2 (COX-2) mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR). Cell proliferation and cell cycle were detected by MTT and flow cytometry (FCM), respectively. The protein expressions of caspase-3 and p65 in MDA-MB-231 cells were detected by western blot. RESULTS: After incubation with different concentrations of celecoxib for 48 h, COX-2 mRNA expression in MDA-MB-231 cells was decreased in a dose-dependent manner compared with untreated cells (P<0.05). Proliferation of MDA-MB-231 cells was reduced drastically in a dose-and time-dependent manner after celecoxib treatment (P<0.05). Combination of prostaglandin E2 (PGE2) and celecoxib exerted similar inhibition effect to celecoxib alone on cell growth (P>0.05). High-dose celecoxib induced an increase in the percentage of G0/G1 phase cells accompanied by the change in DNA ploidy. The cellular caspase-3 level was enhanced whereas the p65 level was decreased in celecoxib-treated MDA-MB-231 cells after 24 h in comparison to those in the control cells. CONCLUSION:Celecoxib could inhibit MDA-MB-231 cell proliferation and promote cell apoptosis by down-regulating the NF-kappaB signaling pathway.