沉默lncRNA THAP9-AS1对乳腺癌细胞增殖、凋亡、迁移及侵袭的影响

Effect of silencing lncRNA THAP9-AS1 on the proliferation,apoptosis,migration and invasion of breast cancer cells

目的:探讨沉默长链非编码RNA THAP9反义RNA1(lncRNA THAP9-AS1)对乳腺癌细胞增殖、凋亡、迁移及侵袭的影响。方法:选取贵州省肿瘤医院2017年6月至2020年6月25例乳腺癌患者的癌组织及癌旁组织,采用实时荧光定量PCR(real-time quantitative polymerase chain reaction,RT-qPCR)检测lncRNA THAP9-AS1和miR-505-3p表达水平。将MDA-MB-231细胞随机分为s i-THAP9-AS1组、s i-NC组、miR-505-3p组、miR-NC组、s i-THAP9-AS1+ant i-miR-NC组、si-THAP9-AS1+miR-505-3p inhibitor组。采用四甲基偶氮唑盐比色(methyl thiazolyl tetrazolium,MTT)法检测细胞活性,平板克隆实验检测细胞集落形成数,流式细胞术实验检测细胞凋亡,划痕实验和Transwell检测细胞迁移及侵袭,双荧光素酶报告实验检测lncRNA THAP9-AS1和miR-505-3p的靶向关系。结果:与癌旁组织相比,乳腺癌组织中lncRNA THAP9-AS1的表达水平升高,miR-505-3p的表达水平降低(P<0.05)。沉默lncRNA THAP9-AS1或过表达miR-505-3p可降低细胞活性及迁移距离,减少集落形成数和侵袭细胞数,增加细胞凋亡率,增加E-cadherin蛋白表达水平升高,并降低N-cadherin蛋白表达水平(P<0.05)。LncRNA THAP9-AS1靶向调控miR-505-3p;抑制miR-505-3p逆转了沉默lncRNA THAP9-AS1对MDA-MB-231增殖、迁移及侵袭的影响。结论:沉默lncRNA THAP9-AS1可通过增加miR-505-3p抑制乳腺癌细胞增殖、迁移及侵袭,并抑制凋亡。

Objective:To explore the effect of silencing lncRNA THAP9-AS1 on the proliferation,apoptosis,migration and invasion of breast cancer cells.Methods:The cancer tissues and adjacent tissues were collected from 25 breast cancer patients at Guizhou Cancer Hospital from June 2017 to June 2020.The expression levels of lncRNA THAP9-AS1 and miR-505-3p were detected by real-time quantitative polymerase chain reaction(RT-qPCR).MDA-MB-231 cells were randomly divided into the si-THAP9-AS1 group,the si-NC group,the miR-505-3p group,the miR-NC group,the si-THAP9-AS1+anti-miR-NC group,and the si-THAP9-AS1+miR-505-3p inhibitor group.Cell activity was detected by methyl thiazolyl tetrazolium(MTT)method;cell colony formation was detected by plate cloning assay;cell apoptosis was detected by flow cytometry assay;cell migration and invasion were detected by scratching assay and Transwell assay;dual luciferase reporting assay was used to detect the targeting relationship between lncRNA THAP9-AS1 and miR-505-3p.Results:The expression level of lncRNA THAP9-AS1 was increased in breast cancer tissues compared with adjacent tissues,while the expression level of miR-505-3p was decreased(P<0.05).Silencing lncRNA THAP9-AS1 or miR-505-3p overexpression could inhibit cell viability and migration,decrease the number of colonies and invaded cells,increase the rate of apoptosis and the protein level of E-cadherin,and reduce the protein level of N-cadherin(P<0.05).Moreover,lncRNA THAP9-AS1 targeted miR-505-3p,and inhibition of miR-505-3p reversed the effects of lncRNA THAP9-AS1 silence on the proliferation,migration and invasion of MDA-MB-231 cells.Conclusion:Silencing lncRNA THAP9-AS1 can inhibit the proliferation,migration and invasion and promote apoptosis of breast cancer cells by up-regulating miR-505-3p.