Reversal Effect Of EGCG On Cisplatin Resistance In Cervical Cancer Cell Line SiHa/DDP

Objective:To investigate the reversal effect of epigallocatechin-3-gallate?EGCG?on cisplatin resistance of human cervical cancer cell line SiHa/DDP and its related mechanisms.Methods:Cisplatin with different concentrations were used in SiHa/DDP cells group and SiHa cells group,MTT assay was used to detect the proliferation inhibition rate of the two cells,and the IC₅₀0 of the two groups and SiHa/DDP cell resistance index were calculated to verify the cisplatin resistance of SiHa/DDP cells.MTT assay was used to determine the proliferation inhibition rate of SiHa/DDP cells treated with different concentrations of EGCG.IC₅ was used as the non-cytotoxic concentration of EGCG,which was the best reversal of drug resistance concentration in subsequent experiments.In order to clarify the reversal effect of EGCG on cisplatin resistance in SiHa/DDP cells,the control group,cisplatin group and cisplatin+EGCG group were established.MTT method was used to calculate the proliferation inhibition rate of each group,IC₅₀0 of each group was obtained,and the drug resistance reversal fold of EGCG to SiHa/DDP cells was calculated.Western blot was used to detect the expression of drug resistance-related proteins P-gp and ABCG2 in the control group,cisplatin group and cisplatin+EGCG group,and the differences of protein expression and differences grey level in each group was observed to investigate the possible mechanism by which EGCG reverses cisplatin resistance in SiHa/DDP cells.Result:1.SiHa cells were treated with different concentrations of cisplatin?0.625?g/ml,1.25?g/ml,2.5?g/ml,5?g/ml?for 48 hours.The inhibition rates of SiHa cells were 18.37%,24.72%,52.86%and 82.60%,respectively.When treated with corresponding concentrations of cisplatin,The inhibition rates of SiHa/DDP cells was 4.39%,7.65%,11.58%and25.45%respectively.The IC₅₀0 of the two groups were 2.13 and 15.81respectively.The resistance index of SiHa/DDP cells was RI=IC₅₀?SiHa/DDP group?/IC₅₀?SiHa group?=15.81/2.13=7.42.Statistically significant?P<0.05?.2.After treatment of SiHa/DDP cells were treated with different concentrations of EGCG?5?g/ml,10?g/ml,20?g/ml,40?g/ml,80?g/ml?for 48 hours,the cell proliferation inhibition rate of each group by MTT assay was 4.60%,9.39%,23.94%,39.59%,60.22%,and SiHa/DDP cells with EGCG at the concentration of 5?g/ml,the cell proliferation inhibition rate was less than 5%,which participated in the subsequent experiment as an optimal reversal drug resistance concentration.3.SiHa/DDP cells were treated with different concentrations of cisplatin combined with 5?g/ml EGCG treat with SiHa/DDP cells for 48hours,the cell proliferation inhibition rates were 11.54%,23.41%,39.29%and 78.02%respectively,and the IC₅₀0 was 2.68.After 48 hours of cisplatin alone,the cell inhibition rates were 4.39%,7.65%,11.58%,25.45%,and the IC₅₀0 was 15.81.the drug resistance reversal fold RI=IC₅₀?cisplatin group?/IC₅₀?cisplatin+EGCG group?=15.81/2.68=6.06,the difference was statistically significant?P<0.05?.4.After cisplatin was applied to SiHa/DDP cells,the expressions of drug-related proteins P-gp were higher than those in the control group,and the difference was statistically significant?P<0.05?.After cisplatin combined with EGCG was applied to SiHa/DDP cells,the expression of the P-gp and ABCG2 were significantly lower than that of the control group and the cisplatin group?P<0.05?.Conclusion:EGCG can reverse the cisplatin-resistant human cervical cancer cell line SiHa/DDP,which may be related to the the inhibitory of expression of P-gp and ABCG2 in the cells.