miR-221/222靶向抑制对三阴性乳腺癌MDA-MB-231细胞顺铂敏感性的影响

Effect of miR-221/222 targeted inhibition on Cisplatin sensitivity of triple-negative breast cancer MDA-MB-231 cells

目的探讨微RNA(miR)-221/222靶向抑制对三阴性乳腺癌(TNBC)MDA-MB-231细胞顺铂(DDP)敏感性的影响。方法随机将MDA-MB-231细胞分为对照组、miR-221抑制组、miR-222抑制组和miR-221/222抑制组,分别转染空白试剂、miR-221抑制剂、miR-222抑制剂和miR-221/222抑制剂,转染后均给予DDP 5μg/mL进行培养。以荧光定量聚合酶链式反应检测miR-221/222 mRNA的相对表达量,以MTT法检测细胞增殖抑制率,以Annexin V-FTTC/PI双染法检测细胞凋亡率,以蛋白质印迹法分析凋亡相关蛋白的水平。结果miR-221 mRNA的表达水平比较,miR-221抑制组低于对照组,miR-222抑制组高于miR-221抑制组,miR-221/222抑制组低于miR-222抑制组,差异均有统计学意义(均P<0.05);miR-222抑制组和miR-221/222抑制组miR-222 mRNA的表达水平低于miR-221抑制组和对照组,差异均有统计学意义(均P<0.05);miR-221/222抑制组转染后24、48 h的细胞增殖抑制率及细胞凋亡率均高于其余三组,差异均有统计学意义(均P<0.05);miR-221/222抑制组转染后48 h细胞Caspase-9和Bax水平高于其余三组,Bcl-2水平低于其余三组,差异均有统计学意义(均P<0.05)。结论共抑制miR-221/222可增加MDA-MB-231细胞的DDP敏感性。

Objective To investigate the Cisplatin(DDP)sensitivity of microRNA(miR)-221/222 targeted inhibition on triple-negative breast cancer(TNBC)MDA-MB-231 cells.Methods MDA-MB-231 cells were randomly divided into control group,miR-221 inhibition group,miR-222 inhibition group and miR-221/222 inhibition group,transfected with blank reagent,miR-221 inhibitor,miR-222 inhibitor and miR-221/222 inhibitor respectively,and after transfection,DDP 5μg/mL was given for culture.Relative expression of miR-221/222 mRNA was detected by fluorescence quantitative polymerase chain reaction,inhibition rate of cell proliferation was detected by MTT method,apoptosis rate was detected by Annexin V-FTTC/PI double staining method,and the expression levels of apoptosis related proteins were detected by Western blot.Results Comparing the expression level of miR-221 mRNA,the miR-221 inhibition group was lower than the control group,the miR-222 inhibition group was higher than the miR-221 inhibition group,and the miR-221/222 inhibition group was lower than the miR-222 inhibition group,and the differences were statistical significance(all P<0.05).The expression level of miR-222 mRNA in the miR-222 inhibition group and miR-221/222 inhibition group were lower than that of the miR-221 inhibition group and the control group,and the differences were statistically significant(all P<0.05).The inhibition rate of cell proliferation and apoptosis of the miR-221/222 inhibition group was higher than that of the other three groups at 24 and 48 h after transfection,and the differences were statistically significant(all P<0.05).The levels of Caspase-9 and Bax in the miR-221/222 inhibition group were higher than those of the other three groups at 48 h after transfection,and the Bcl-2 level was lower than that of the other three groups,and the differences were statistically significant(all P<0.05).Conclusion Co-inhibition of miR-221/222 can increase DDP sensitivity of MDA-MB-231 cells.