Department of Breast Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China.
J Cell Biochem. 2020 Oct;121(10):4176-4187. doi: 10.1002/jcb.29572. Epub 2020 Jan 10.
Triple-negative breast cancer (TNBC) is one of the malignant type of breast cancer. Previous study indicated that long noncoding RNA (lncRNA) ZEB1-AS1 was associated with the progression of several cancers. However, its underlying molecular mechanism in TNBC remains to be elucidated. In this study, ZEB1-AS1 expression was boosted in TNBC tissues and cell lines according to reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Inhibition of ZEB1-AS1 suppressed cell proliferation, migration, invasion, and promoted cell apoptosis in TNBC. Moreover, ZEB1-AS1 positively regulated ZEB1 expression. RT-qPCR disclosed ZEB1 expression was elevated in TNBC tissues and ZEB1 silence blocked TNBC progression. RNA pull-down and RNA immunoprecipitation assays revealed ZEB1-AS1 and ZEB1 both could bind with ELAVL1. ZEB1-AS1 maintained ZEB1 messenger RNA (mRNA) stability by binding with ELAVL1. In addition chromatin, immunoprecipitation and luciferase reporter assays confirmed that ZEB1 could bind with ZEB1-AS1 promoter and promoted ZEB1-AS1 expression. Rescue assays manifested ZEB1 overexpression could abolish the inhibitory effect caused by ZEB1-AS1 inhibition on TNBC progression. To sum up, ZEB1 induced-upregulation of ZEB1-AS1 maintained the stability of ZEB1 mRNA by binding with ELAVL1, which formed a feedback loop to facilitate TNBC progression. These findings might provide a new target for TNBC treatment.
三阴性乳腺癌(TNBC)是乳腺癌的恶性类型之一。先前的研究表明,长链非编码 RNA(lncRNA)ZEB1-AS1 与几种癌症的进展有关。然而,其在 TNBC 中的潜在分子机制仍有待阐明。在这项研究中,根据逆转录定量聚合酶链反应(RT-qPCR),在 TNBC 组织和细胞系中上调了 ZEB1-AS1 的表达。抑制 ZEB1-AS1 可抑制 TNBC 细胞的增殖、迁移和侵袭,并促进细胞凋亡。此外,ZEB1-AS1 可正向调节 ZEB1 的表达。RT-qPCR 显示 ZEB1 在 TNBC 组织中表达上调,而 ZEB1 沉默则阻断了 TNBC 的进展。RNA 下拉和 RNA 免疫沉淀试验表明,ZEB1-AS1 和 ZEB1 均可与 ELAVL1 结合。ZEB1-AS1 通过与 ELAVL1 结合来维持 ZEB1 mRNA 的稳定性。此外,染色质免疫沉淀和荧光素酶报告基因检测证实 ZEB1 可与 ZEB1-AS1 启动子结合,并促进 ZEB1-AS1 的表达。挽救试验表明,ZEB1 的过表达可以消除 ZEB1-AS1 抑制对 TNBC 进展的抑制作用。总之,ZEB1 通过与 ELAVL1 结合诱导 ZEB1-AS1 的上调,从而维持 ZEB1 mRNA 的稳定性,形成反馈环以促进 TNBC 的进展。这些发现可能为 TNBC 的治疗提供新的靶点。