微小RNA-525-5p通过靶向RECQ样蛋白5调控乳腺癌放射敏感性  

MicroRNA-525-5p regulates radiosensitivity of breast cancer by targeting RECQ protein-like 5

作　　者：梁猛 LIANG Meng(Oncology Department,Shiyan Taihe Hospital(The Affiliated Hospital of Hubei Medical College),Shiyan,Hubei 442000,China)

机构地区：[1]十堰市太和医院(湖北医药学院附属医院)肿瘤科,湖北十堰442000

出　　处：《安徽医药》2022年第10期2032-2037,I0003,共7页Anhui Medical and Pharmaceutical Journal

摘　　要：目的探讨微小RNA-525-5p(miR-525-5p)对乳腺癌细胞辐射照射敏感性的影响及机制。方法该研究起止时间为2019年6月至2020年6月,人乳腺癌细胞MDA-MB-231、MCF-7、BT474、非恶性乳腺上皮细胞MCF-10A均购自美国菌种保藏中心。运用qRT-PCR法检测人乳腺癌细胞MDA-MB-231、MCF-7、BT474、非恶性乳腺上皮细胞MCF-10A中miR-525-5p的mRNA的表达;将miR-525-5p模拟物(miR-525-5p mimics)阴性对照(miR-NC)组(转染miR-NC)、miR-525-5p组(转染miR-525-5p mim‐ics)、RECQL5小干扰RNA阴性对照(si-NC)组(转染si-NC)、RECQL5小干扰RNA(si-RECQL5)组(转染si-RECQL5)、miR-525-5p+RECQL5过表达空载体(pcDNA)组(共转染miR-525-5p mimics和pcDNA)、miR-525-5p+RECQL5过表达载体(pcDNA-REC‐QL5)组(共转染miR-525-5p mimics和pcDNA-RECQL5),均用脂质体法转染至MDA-MB-231细胞;Western blotting检测细胞中RECQ样蛋白5(RECQL5)的蛋白表达;流式细胞术检测细胞凋亡;双荧光素酶报告基因检测实验检测细胞的荧光活性;克隆形成实验检测细胞的存活分数。结果与非恶性乳腺上皮细胞MCF-10A相比,人乳腺癌细胞MDA-MB-231、MCF-7、BT474中miR-525-5p表达[0.28±0.02,0.33±0.02,0.42±0.03比1.01±0.08]显著降低,RECQL5 mRNA和蛋白表达[1.68±0.15,1.58±0.12,1.48±0.11比1.00±0.08;1.43±0.11,1.38±0.12,1.53±0.14比0.99±0.07]显著升高(P<0.05)。过表达miR-525-5p或敲减RECQL5均可促进乳腺癌细胞MDA-MB-231凋亡,增强对辐射照射的敏感性。miR-525-5p可抑制野生型RECQL5细胞的荧光活性,并负向调控RECQL5的表达。过表达RECQL5可逆转miR-525-5p对乳腺癌细胞的凋亡促进及辐照增敏作用。结论miR-525-5p可促进乳腺癌细胞凋亡,增强对辐射照射的敏感性,其机制与靶向RECQL5有关,将可为乳腺癌的放射治疗提供新方向。Objective To investigate the effect and mechanism of microRNA-525-5p(miR-525-5p)on the sensitivity of breast cancer cells to radiation exposure.Methods The start and end time of this study was from June 2019 to June 2020.Human breast cancer cell MDA-MB-231,MCF-7,BT474 and non-malignant mammary epithelial cell MCF-10A were purchased from the American Culture Collection.qRT-PCR was used to detect the expressions of miR-525-5p mRNA in human breast cancer cell line MDA-MB-231,MCF7,BT474 and non-malignant mammary epithelial cell MCF-10A;miR-525-5p mimics negative control(miR-NC)group(transfected miR-NC),the miR-525-5p group(transfected miR-525-5p mimics),RECQL5 small interfering RNA negative control(si-NC)group(transfected si-NC),RECQL5 small interfering RNA(si-RECQL5)group(transfected si-RECQL5),miR-525-5p+RECQL5 overexpression empty vector(pcDNA)group(co-transfected miR-525-5p mimics and pcDNA),and miR-525-5p+RECQL5 overexpression vector(pcDNA-RECQL5)group(co-transfected miR-525-5p mimics and pcDNA-RECQL5)all transfected into MDA-MB-231 cells by liposome.The protein expression of RECQ protein-like 5(RECQL5)in cells was detected by Western blotting,the apoptosis was detected by flow cytometry,and the fluorescence activity of cells was detected by double luciferase reporter gene assay.The colony formation assay detected the survival fraction of the cells.Results Compared with non-malignant mammary epithelial cells MCF-10A,the expressions of miR-525-5p[(0.28±0.02),(0.33±0.02),(0.42±0.03)vs.(1.01±0.08)]were significantly decreased and the mRNA and protein expressions of RECQL5[(1.68±0.15),(1.58±0.12),(1.48±0.11)vs.(1.00±0.08);(1.43±0.11),(1.38±0.12),(1.53±0.14)vs.(0.99±0.07)]were significantly increased in human breast cancer cells MDA-MB-231,MCF-7 and BT474(P<0.05).Overexpression of miR-525-5p or knockdown of RECQL5 could both promote the apoptosis of breast cancer cells MDA-MB-231 and enhance the sensitivity to radiation exposure.MiR-525-5p inhibited the fluorescence activity of wild-type RECQL5 cells and

关 键 词：乳腺肿瘤 RecQ解旋酶类 微小RNA-525-5p 放射敏感性 

分 类 号：R737.9[医药卫生—肿瘤]