miRNA-4429对乳腺癌细胞增殖、迁移、侵袭、凋亡的影响及作用机制

Effect and mechanism of miRNA-4429 on proliferation,migration,invasion and apoptosis of breast cancer cells

目的 探讨微小RNA(miRNA)-4429对乳腺癌细胞增殖、迁移、侵袭、凋亡的影响及作用机制。方法收集100例乳腺癌患者的乳腺癌组织和癌旁组织,采用实时荧光定量逆转录聚合酶链反应(qRT-PCR)检测miRNA-4429和磷脂酰肌醇-3-激酶调节亚基1(PIK3R1)mRNA相对表达量。培养乳腺癌MDA-MB-231细胞,将脂质体转染试剂Lipo6000?分别与miRNA-4429模拟物(miRNA-4429 mimic)、miRNA-4429抑制物(miRNA-4429 inhibitor)、模拟物阴性对照(NC)混合均匀,分别作为miRNA-4429 mimic组、miRNA-4429 inhibitor组、NC组。采用克隆形成实验检测细胞增殖能力,Transwell实验检测细胞迁移和侵袭能力,流式细胞术检测细胞凋亡情况,qRTPCR检测PIK3R1 mRNA相对表达量,蛋白质印迹法检测PIK3R1蛋白表达情况。结果 乳腺癌组织中miRNA-4429、PIK3R1 mRNA相对表达量均明显低于癌旁组织,差异均有统计学意义(P﹤0.01)。miRNA-4429 mimic组克隆形成率、迁移细胞数目、侵袭细胞数目均低于NC组,miRNA-4429 inhibitor组克隆形成率、迁移细胞数目、侵袭细胞数目均高于NC组,差异均有统计学意义(P﹤0.05)。miRNA-4429 mimic组细胞早期凋亡率、晚期凋亡率及总凋亡率均高于NC组,miRNA-4429 inhibitor组细胞早期凋亡率、晚期凋亡率及总凋亡率均低于NC组,差异均有统计学意义(P﹤0.05)。miRNA-4429 mimic组细胞中PIK3R1 mRNA和蛋白相对表达量均低于NC组,miRNA-4429 inhibitor组细胞中PIK3R1 m RNA和蛋白相对表达量均高于NC组,差异均有统计学意义(P﹤0.05)。结论乳腺癌组织中miRNA-4429表达水平较低,miRNA-4429通过调控PIK3R1的表达抑制乳腺癌细胞增殖、迁移和侵袭,并促进乳腺癌细胞凋亡,可能成为治疗乳腺癌的新靶点。

Objective To investigate the effect and mechanism of microRNA(miRNA)-4429 on proliferation,migration,invasion and apoptosis of breast cancer cells.Method The breast cancer tissues and paracancerous tissues of 100patients with breast cancer were collected.The relative expression of miRNA-4429 and phosphoinositide-3-kinase regulatory subunit 1(PIK3R1) m RNA were detected by real-time quantitative reverse transcription-polymerase chain reaction(qRT-PCR).MDA-MB-231 cells were cultured and the liposome transfection reagent Lipo6000? was mixed with miRNA-4429 mimic,miRNA-4429 inhibitor and negative control(NC),respectively,as miRNA-4429 mimic group,miRNA-4429 inhibitor group and NC group.Cell proliferation was detected by clone formation assay,cell migration and invasion were detected by Transwell assay,cell apoptosis was detected by flow cytometry,and the expression of PIK3R1 mRNA and protein were detected by q RT-PCR and Western blot.Result The relative expression of miRNA-4429 and PIK3R1mRNA in breast cancer tissues were lower than those in paracancerous tissues(P<0.01).The clone formation rate,migration cell number and invasion cell number of miRNA-4429 mimic group were lower than those of NC group,while those of miRNA-4429 inhibitor group were higher than those of NC group,and the differences were statistically significant(P<0.05).The early and late apoptosis rates and overall apoptosis rate of miRNA-4429 mimic group were higher than those of NC group,while those of miRNA-4429 inhibitor group were lower than those of NC group,and the differences were statistically significant(P<0.05).The relative expression of PIK3R1 mRNA and protein in miRNA-4429 mimic group were lower than those in NC group,while those in miRNA-4429 inhibitor group were higher than those in NC group,and the differences were statistically significant(P<0.05).Conclusion The expression of miRNA-4429 is low in breast cancer tissues.By regulating the expression of PIK3R1,miRNA-4429 can inhibit the proliferation,migration and invasion of breast cancer cells,and promote the apoptosis of breast cancer cells,which may become a new target for the treatment of breast cancer.