Abstract:Objective To investigate the potential role of PI3K/Akt pathway in the anti-bladder tumor effect of selective cyclooxygenase-2(Cox-2)inhibitor celecoxib.Methods Adherent T24 cells were treated with different concentrations of PI3 Kinhibitor LY294002 and the proliferation activity of T24 cells was determined using the MTT assay.In addition,both adherence-and suspension-cultured T24 cells were challenged with celecoxib,PGE2and LY294002,respectively.Apoptosis rate of T24 cells was measured by flow cytometry and Akt activation in suspension-cultured T24 cells was determined by Western blotting after treatment with celecoxib and PGE2.Results Celecoxib treatment induced apoptosis in both adherence-and suspension-cultured T24 cells.Both PGE2and LY294002 had no significant effects on the proliferation and apoptosis in adherent T24 cells.However,PGE2inhibited apoptosis in suspension-cultured cells and LY294002 increased cell anoikis.Western blot analysis revealed that Akt activation was suppressed by celecoxib but was enhanced by PGE2.Conclusion Celecoxib inhibits proliferation and induces apoptosis of T24 cells through PI3K/Akt pathway involving the inhibition of Akt phosphorylation.