The effect and mechanism of cyclooxygenase-2 selective inhibitor NS-398 on the proliferation and apoptosis of human mammary adenocarcinoma MCF-7 cell

Objective To investigate the effects and mechanism of a cyclooxygenase-2(COX-2) selective inhibitor NS-398 on the proliferation and apoptosis of mammary adenocarcinoma MCF-7 cell. MethodsAfter the treatment with NS-398 on MCF-7 cell,MTT assay was used to observe the inhibition of MCF-7 cell growth and apoptosis was detected by flow cytometry.The expression of COX-2,Bcl-2 and Bax was detected by flow cytometry.The content of PGE2 in the supernatants of cell culture was measured by radioimmunoassay(RIA). ResultsNS-398 may inhibit the proliferation of MCF-7 cells in a concentration-and time-dependent manner.Meanwhile NS-398 treatment resulted in an increase of G0/G1-phase cells(P0.01) and a decrease of S-and G2/M-phase cells(P0.01).The apoptosis of MCF-7 cells was also obviously increased after NS-398 treatment.COX-2,Bcl-2 and PGE2 protein expression was down-regulated(P0.01),while Bax protein expression was up-regulated(P0.01) after NS-398 treatment. ConclusionNS-398 may inhibit the proliferation and induce the apoptosis of MCF-7 cell through the inactivation of COX-2,down-regulation of PGE2 and Bcl-2 expression,and up-regulation of Bax expression.