Study On The Apoptosis Of Human Breast Cancer Cell MDA-MB-231 Induced By Arsenic Trioxide Combined With Tunicamycin

Objective:To investigate the effect of arsenic trioxide(As2O3)combined with Tunicamycin(TM)on the apoptosis of human triple-negative breast cancer cell MDA-MB-231 and its mechanism.Methods:Human hepatocellular carcinoma cell MDA-MB-231 was used as a model and routine cell culture.The experiment was treated with As2O3 group,TM group and combination group.As2O3 group and TM group were set to the following concentrations[Blank control(DMEVM)?control(DMEM + NaOH/DMSO,0.1,0.5,1,10,20,40,60,80 ?mol/L)],The cells were induced for 24 h,and the cell proliferation inhibition rate was detected by MTT assay;According to the cell proliferation inhibition rate,0.5?mol/L TM was chosen as the fixed concentration,combined with different concentrations of As2O3 as the combined group for 24 hours,and then MTT assay was used to detect the cell proliferation inhibition rate.Morphological changes were observed under inverted microscope.Flow cytometry was used to detect the apoptotic rate and mitochondrial membrane potential.Western blot was used to detect the protein expression of glucose-regulated protein 78(GRP78)and the expression of ERS-related protein Caspase4 in endoplasmic reticulum stress ERS.According to GRP78 protein expression,1?mol/L As2O3 combined with 0.5?mol/L TM group was selected,The cells were pretreated with 4-phenyl butyric acid 4-PBA for 2 hours,and the effect of the cells was observed 24 hours later.Results:1.MTT results showed that As2O3 group had both pro-proliferation and pro-apoptotic effect on cells,and proliferated and promoted apoptosis at 10?mol/L after 0.1,0.5 and 1?mol/L(P<0.05),compared with the control group(P<0.05).TM group had a growth inhibitory effect on breast cancer cells,and the proliferation inhibition rate was sigrnificantly higher than that of the control group(P<0.05).As2O3 combined with TM group to induce cells,the inhibition rate of cell growth was not offset by the effect of As2O3 combined with TM at 0.1,1?mol/L,but the proliferation inhibition rate was significantly increased(P<0.05).There was significant difference between the two groups(P<0.05).2?The control cells in the As2O3 group,the TM group and the two groups were in good condition,and the morphology was full and the spindle shape was large.The density of the adherent cells decreased with the increase of the drug dose.Shrink round,debris increased significantly,and a large number of cells floating.3.The apoptosis rates of As2O3 were 13.7%± 1.06 and 16.3%± 1.22,respectively,when the cells were treated with O.11?mol/L,1?mol/L,1Olpmol/L,20?mol/L and 40?mol/L for 24 hours(P<0.05).The apoptotic rates of the combination were 20.5%± 0.66 and 22.8%± 0.46,respectively,and the difference was significant(P<0.05)23.6 ± 0.95,43.3 ±0.74,51.4%± 0.76,which was significantly different from the control group(12.0%±1.15),which was statistically significant(P<0.05).4?Different concentrations of As2O3 combined 0.5?mol/L TM induction cells,mitochondrial membrane potential of the cell decreased significantly,there is a significant difference compared with the control group,with statistical significance(P<0.05).5?As2O3 induced no significant increase in the expression of GRP78 in breast cancer cells,and there was no significant difference compared with the control group(P>0.05).TM-induced breast cancer cells visible ERS GRP78 significantly upregulated to 12 ?mol/L TM cells induce expression of GRP78 ERS highest,compared with control group difference was statistically significant(P<0.05);The expression of GRP78 was the highest at 1?mol/L As2O3 combined with 0.5 pmol/L TM,which was statistically significant(P<0.05)compared with the control group.6.TM can upregulate the expression of caspase4 induced breast cancer cells when ERS,the difference compared with the control group was statistically significant(P<0.05);As2O3 combined with TM induced breast cancer cells,the expression of caspase4 was not up-regulated or down-regulated,and there was no significant difference compared with the control group(P>0.05).7?pretreatment with 4-PBA cells for 2 h,TM induced cells for 24 hours,showing caspase4 protein upregulation was blocked,and without 4-PBA pretreatment group were statistically significant difference(P<0.05);The expression of caspase4 protein was not changed by As2O3 combined with TM,and it was not statistically significant compared with As2O3(TM)group(P>0.05).Conclusion:1As2O3 combined with TM induced apoptosis of human breast cancer MDA-MB-231 cells was superior to single drug;2.1 ?mol/L As2O3 combined with 0.5 ?mol/L TM could synergistically promote the apoptosis of MDA-MB-231 cells.TM can reverse the proliferation promoting effect of As2O3 to inhibit proliferation and promote apoptosis;3?As2O3 combined with TM induced apoptosis of human breast cancer MDA-MB-231 cells through mitochondria and endoplasmic reticulum stress.