Based on public databases and bioinformatics analyses, the low expression of lncRNA MIDEAS-AS1 in breast cancer tissues was detected and further validated in a cohort of TNBC tissues. The effects of MIDEAS-AS1 on proliferation, migration, invasion were determined by in vitro and in vivo experiments. RNA pull-down assay and RNA immunoprecipitation (RIP) assay were carried out to reveal the interaction between MIDEAS-AS1 and MATR3. Luciferase reporter assay, Chromatin immunoprecipitation (ChIP) and qRT-PCR were used to evaluate the regulatory effect of MIDEAS-AS1/MATR3 complex on NCALD.
LncRNA MIDEAS-AS1 was significantly downregulated in TNBC, which was correlated with poor overall survival (OS) and progression-free survival (PFS) in TNBC patients. MIDEAS-AS1 overexpression remarkably inhibited tumor growth and metastasis in vitro and in vivo. Mechanistically, MIDEAS-AS1 mainly located in the nucleus and interacted with the nuclear protein MATR3. Meanwhile, NCALD was selected as the downstream target, which was transcriptionally regulated by MIDEAS-AS1/MATR3 complex and further inactivated NF-κB signaling pathway. Furthermore, rescue experiment showed that the suppression of cell malignant phenotype caused by MIDEAS-AS1 overexpression could be reversed by inhibition of NCALD.
Collectively, our results demonstrate that MIDEAS-AS1 serves as a tumor-suppressor in TNBC through modulating MATR3/NCALD axis, and MIDEAS-AS1 may function as a prognostic biomarker for TNBC.
方法:基于公共数据库和生物信息学分析,检测到lncRNAMIDEAS-AS1在乳腺癌组织中的低表达,并在TNBC组织队列中进一步验证.MIDEAS-AS1对增殖的影响,迁移,通过体外和体内实验确定侵袭。进行RNA下拉测定和RNA免疫沉淀(RIP)测定以揭示MIDEAS-AS1和MATR3之间的相互作用。荧光素酶报告基因测定,染色质免疫沉淀(ChIP)和qRT-PCR用于评估MIDEAS-AS1/MATR3复合物对NCALD的调节作用。
结果:LncRNAMIDEAS-AS1在TNBC中显著下调,这与TNBC患者的总生存期(OS)和无进展生存期(PFS)相关。MIDEAS-AS1过表达在体外和体内均显着抑制肿瘤的生长和转移。机械上,MIDEAS-AS1主要位于细胞核中,并与核蛋白MATR3相互作用。同时,NCALD被选为下游目标,受MIDEAS-AS1/MATR3复合物的转录调控,并进一步灭活NF-κB信号通路。此外,拯救实验表明,MIDEAS-AS1过表达引起的细胞恶性表型抑制可以通过抑制NCALD逆转。
结论:总的来说,我们的结果表明,MIDEAS-AS1通过调节MATR3/NCALD轴在TNBC中充当肿瘤抑制因子,和MIDEAS-AS1可能作为TNBC的预后生物标志物。