The Effect Of FOXO3a On Breast Cancer MDA-MB-231 Cell Growth, Proliferation And Cisplatin Chemotherapy Sensitivity

Objective: Construction of a high expression cell strain of FOXO3 a to explore the effect of FOXO3 a on growth and proliferation in breast cancer MDA-MB-231 cell line.Methods: The experiment was divided into three groups: blank group Control group(normal MDA-MB-231 cell group),negative control group NC group(MDA-MB-231 cell group transfected with empty plasmid),experimental group FOXO3 a group(transfection)MDA-MB-231 cell group of FOXO3 a plasmid).1)The MDA-MB-231 cell line was transfected with the FOXO3 a plasmid vector and the empty vector,respectively,and a cell line highly expressing FOXO3 a and a cell line transfected with an empty vector were constructed.2)The content of FOXO3 a protein in three groups of cells was detected by Western Blot(WB)to determine whether FOXO3 a was successfully transfected.3)MTT assay was used to detect the proliferation inhibition of the three groups at 24 h,48h,72 h and 96 h.4)7-AAD/PI-Annexin V staining flow cytometry was used to detect the apoptosis of each cell line for 24 hours.5)Scratch test to detect the migration ability of the three groups of cells at 0h,24 h and 48 h.6)Transwell assay was used to detect the invasive ability of the three groups of cells at 0h,24 h and 48 h.Results: 1)Western Blot results showed that FOXO3 a protein expression levels were different in the three groups of cells,and the relative expression of FOXO3 a group was significantly higher than that of Control group and NC group(P<0.05),while FOXO3 a of Control group and NC group were significantly higher.There was no significant difference in the relative expression of protein(P>0.05).2)The results of MTT assay showed that the survival rates of the three groups of cells were different.The cell proliferation inhibition rate of FOXO3 a group was significantly higher than that of Contorl group(P=0.013<0.05)and NC group(P=0.012<0.05).Academic significance;Contorl group and NC group were not significantly different(P>0.05).3)Flow cytometry results of 7-AAD/PE-Annexin V staining showed that the apoptosis rate of FOXO3 a group(13.37±0.25)% was significantly higher than that of Contorl group(8.38±0.45)% and NC group(9.18±0.23).%),the difference was statistically significant(P<0.05);there was no significant difference in apoptosis rate between Contorl group and NC group(P>0.05).4)The scratch test results showed that the scratch repair rate of the three groups of cells was different,and the scratch repair rate of the FOXO3 a group(42.07±1.76%)was significantly lower than that of the Contorl group(48.73±1.25%,P=0.002<0.05).There was a statistically significant difference between the NC group and the NC group(48.27±1.6%,P=0.003<0.05).There was no significant difference between the Contorl group and the NC group(P>0.05).5)Transwell results showed that the invasive ability of the three groups of cells was different.The number of Transwell membrane cells in the FOXO3 a group(56.33±4.51)was significantly lower than that in the Contorl group(80.24±5.57,P=0.011<0.05)and the NC group(92.43).±3.51,P=0.007<0.05),the difference was statistically significant,but there was no significant difference between Contorl group and NC group(P>0.05).Conclusion:1.FOXO3 a inhibits the proliferation,migration and invasion of breast cancer MDA-MB-231 cells,promotes apoptosis,and may play an inhibitory role in the development,metastasis and invasion of breast cancer.Objective: To explore the effect of FOXO3 a on cisplatin chemotherapy sensitivity in breast cancer cells.Methods: The experiment was divided into 6 groups: Control group,NC group,FOXO3 a group,DDP(cisplatin)group,DDP+NC group,DDP+FOXO3a group.1)MTT assay for different concentrations of cisplatin(1?g/ml,10?g/ml,20?g/ml,40?g/ml,60?g/ml,80?g/ml,120?g/ml,160?g/ml)for MDA-MB-231 cells The cell proliferation inhibition rate at 24 h,48h and 72 h was screened to select the optimal cisplatin concentration.2)7-AAD/PE-Annexin V staining flow cytometry was used to detect the apoptosis rate of DDP group,DDP+NC group and DDP+FOXO3a group after adding cisplatin(20?g/ml).3)MTT assay was used to detect the inhibition of proliferation of the three groups of cells treated with cisplatin(20?g/ml)at 0h,24 h,48h,72 h and 96 h.Results: 1)The MTT assay showed that the IC50 of cisplatin concentration was 20 ?g/ml.2)Flow cytometry results showed that there was a statistically significant difference in apoptosis rate between DDP group(36.20±0.29),DDP+NC group(35.54±0.72)and DDP+FOXO3a group(46.41±0.77).<0.05),there was no significant difference in apoptosis rate between DDP group and DDP+NC group(P>0.05).3)The results of MTT assay showed that there was no significant difference in cell viability between DDP group,DDP+NC group and DDP+FOXO3a group(P>0.05).There was no significant cell survival rate between DDP group and DDP+NC group.Difference(P>0.05).Conclusion:FOXO3a increased the apoptotic rate of MDA-MB-231 cells treated with cisplatin,which may enhance the sensitivity of triple-negative breast cancer to cisplatin chemotherapy.