Curcumin Combined With 5-FU On Apoptotic And Effect Of The Expression Of NF-κB、Caspase-3 In The MEC-1 Cells

Objective:To Investigate the effect of combination of curcumin and 5-FU on the apoptosis effect and the expression of NF-κB and caspase-3 protein in human salivary mucoepidermoid carcinoma cells（MEC-1）.To provide a theoretical and experimental basis for the clinical combination treatment of mucoepidermoid carcinoma with curcumin and 5-FU.Methods:The experimental group was divided into curcumin group,5-FU group and combination group.The control group was PBS group containing 0.1%DMSO.MEC-1cells were placed in RPMI-1640 culture medium containing 10%fetal bovine serum（FBS）and 1%double antibody;and cultured in 37℃,5%CO₂ incubator.Passaged until the tumor cells were in logarithmic growth phase.（1）MEC-1 cells were treated with curcumin in different concentration（0、20、40、60、80、120μmol/L）at different time（24、48、72h）,and the inhibition rate of cell proliferation was detected by CCK-8 assay.（2）Similarly,the treatment of 5-FU at different concentrations（0、20、40、60、80、120μmol/L）on MEC-1 cells was performed,the inhibition rate of cell proliferation was detected by CCK-8 assay after 24 hours of treatment.The IC₅₀ values of curcumin and5-FU for 24 hours were calculated and used in subsequent experiments.（3）The inhibition rate of cell proliferation in vitro was detected by 24h CCK-8 assay on single use of curcumin and 5-FU respectively and combination use on the MEC-1 cells.（4）MEC-1 cells were treated with curcumin、5-FU and curcumin+5-FU at different concentrations（20、40 and 60μmol/L）.After 12 and 24 hours,apoptosis was detected by flow cytometry.（5）After adding 34.79μmol/L curcumin and 104.6μmol/L 5-FU,the expression of NF-κB and caspase-3 protein in MEC-1 cells treated with MEC-1 cells alone or in combination with Western bolt.Results:（1）Under different concentrations,the proliferation of MEC-1 cells in the experimental group and the control group were compared and the difference was statistically significant(F_group=719.378,P_group<0.01).With the increase of time,the inhibitory effect of curcumin on the proliferation of MEC-1 cells increased(F_time=203.286,(P_time<0.01).There is an interaction between different curcumin concentration and treatment time(F_interaction=12.650,P_interaction<0.01).In other words,curcumin at different time points and different concentrations could inhibit the growth of MEC-1 cells.（2）The inhibitory effect of 5-FU on the proliferation of MEC-1 cells was enhanced with the increase of drug concentration.（3）Comparison of inhibitory effect on the proliferation of MEC-1 cells between the combination group and 34.79μmol/L of curcumin as well as the combination group and 104.6μmol/L of 5-FU,the difference was statistically significant（P<0.05）.The inhibitory effect of combined drug on MEC-1 cells proliferation was stronger than that of single drug.（4）Curcumin、5-FU and the combination of curcumin and5-FU could induce apoptosis of MEC-1 cells.With the increase of concentration,the apoptosis effect on MEC-1 cells induced by each drug group was enhanced.The combination treatment group and curcumin group,the combination group and 5-FU group in inducing apoptosis of MEC-1 cells were statistically significant（P<0.05）,among which the combination group had stronger ability in MEC-1 cell apoptosis inducing.（5）Both curcumin and 5-FU could down-regulate NF-κB and up-regulation Caspase-3.Conclusion:（1）Curcumin and 5-FU can effectively inhibit the proliferation of MEC-1cells and induce the apoptosis of MEC-1 cells with different concentrations of 5-FU.Combination of drugs than single drug on MEC-1 cell growth inhibition and induction of apoptosis stronger.（2）Curcumin combined with 5-FU can effectively inhibit the proliferation of MEC-1 cells and promote the apoptosis of MEC-1 cells.The mechanism may be related to the inhibition of NF-κB activity and up-regulation of caspase-3expression.