Effect And Mechanism Of Celecoxib On The Sensitivity Of SKOV3Ovarian Cancer Cell Lines To Cisplatin

Objective:To observe the effects of celecoxib on enhancing the sensitivity of ovarian cancer cell lines SKOV3to Cisplatin, and its mechanisms in vitro.Methods:1. The cytotoxicity of celecoxib on SKOV3was detected by MTT assay, and drew the nontoxic dose to continue the following tests.2. The cytotoxicity of nontoxic dose celecoxib combined with DDP on SKOV3was also detected by MTT assay at different time points.3. The flow cytometry was carried out to investigate the effect of nontoxic dose celecoxib combined with DDP on apoptosis in ovarian cancer cell line SKOV3.4. mRNA and protein levels of Survivin in SKOV3cell lines were invesitgated after the treated of nontoxic dose celecoxib combined with DDP by Real-time PCR and Western Blot.5. ELISA assay was used to detect the concentration of PGE2in SKOV3cell culture medium after celecoxib and DDP were used.Results:1. MTT assay results showed that COX-2inhibitor celecoxib can inhibite the proliferation of SKOV3cells in a dose-time-dependent manner.When the concentration of celecoxib≤10uM, the growth of SKOV3cells was not inhibited significantly (inhibition rate<10%), so we screened lOuM as a dose to continue the follow-up experiments.2. MTT assay results showed that the growth of SKOV3cells were inhibited significantly by nontoxic dose celecoxib combined with DDP in a time-dependent manner (F=204.287, P=0.000),and the inhibition rate was significantly higher than using celecoxib or DDP alone, the difference was statistically significant (P=0.000); the combined effects of the two drugs after24h、48h、72h were calculated according to Jin’s formual, q values were1.27、 1.37、1.38, respectively, which were>1.15, showing a sensitizing effect.3. FCM assay results showed that after been treated by10uM clecoxib combined with DDP for48h,the apoptosis rate of SKOV3cells was statistically higher than DDP used alone (46.98%vs27.99%).4. The results of RT-PCR and Western Blot showed that the mRNA and protein levels of Survivin in SKOV3cells were decreased significantly after been treated by lOuM clecoxib combined with DDP for48h compared with those using DDP alone,the differences between the two group were statistically significant (P=0.000).5. ELISA results showed that the concentrations of PGE2in SKOV3cell culture medium were not decreased significantly after been treated by lOuM clecoxib combined with DDP for48h compared with those using clecoxib alone,the differences between the two group were not statistically significant (P>0.05). Conclusions:1. Clecoxib could inhibit the proliferation of SKOV3cells in a dose-time-dependent manner.2. lOuM clecoxib could enhance the sensitivity of SKOV3cell lines to cisplatin in a time-dependent manner.3. The possible chemosensitivity mechanism of clecoxib to SKOV3cell lines was that it can down-rugulate the expression of Survivin mRNA and protein,which contribute the SKOV3cells to apoptosis;4. In the chemosensitivity effect of SKOV3cells to cisplatin celecoxib may only play a regulatory role, did not play the role of treatment, it may not dependent on COX-2.