Ma Xingkai, Zhou Jieyu, Liu Jianyong, Wu Geping, Yu Yan, Zhu Hongyan, Liu Jisheng
Department of Otorhinolaryngology, Zhangjiagang First People's Hospital, Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, P.R. China,
Department of Otorhinolaryngology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai, P.R. China.
Onco Targets Ther. 2018 Nov 27;11:8399-8408. doi: 10.2147/OTT.S182573. eCollection 2018.
Antidifferentiation noncoding RNA (ANCR) is a newly identified long noncoding RNA, which is reported to function as an oncogene in multiple human cancers. However, its function in nasopharyngeal carcinoma (NPC) and underlying mechanism are still unclear.
We explored the expression of ANCR in NPC tissues and cells by real-time PCR and analyzed the relationship between ANCR expression and clinicopathological characteristics of NPC patients by Pearson's chi-squared test. Then we inhibited ANCR expression in NPC cells using siRNAs and evaluated the effect of ANCR expression on cell proliferation, colony formation, and radiosensitivity by cell counting kit-8 assay and colony formation assay. We used RT-PCR and Western blot analyses to search target genes of ANCR. Also, we used RNA immunoprecipitation (RIP) assay and chromatin immunoprecipitation assay to study the molecular mechanism in this regulation.
We found that ANCR was upregulated in NPC tissues and cells. ANCR expression was significantly correlated with tumor size and TNM stage. Further, ANCR knockdown inhibited NPC cell growth and radiation resistance. Mechanistically, we found that PTEN was upregulated in ANCR knockdown NPC cells. In addition, RIP assay indicated that EZH2, the oncogenic histone methyltransferase of polycomb repressive complex 2, interacted with ANCR in NPC cells. More importantly, the binding of EZH2 and deposition of relevant negative histone marker H3K27me3 on PTEN promoter depended on ANCR expression.
ANCR expression is upregulated in NPC and promotes NPC growth and radiation resistance through an epigenetic regulation of PTEN expression.
去分化非编码RNA（ANCR）是一种新发现的长链非编码RNA，据报道在多种人类癌症中发挥癌基因作用。然而，其在鼻咽癌（NPC）中的功能及潜在机制仍不清楚。
我们通过实时PCR检测NPC组织和细胞中ANCR的表达，并采用Pearson卡方检验分析ANCR表达与NPC患者临床病理特征之间的关系。然后，我们使用小干扰RNA（siRNAs）抑制NPC细胞中ANCR的表达，并通过细胞计数试剂盒-8检测和集落形成实验评估ANCR表达对细胞增殖、集落形成和放射敏感性的影响。我们使用逆转录-聚合酶链反应（RT-PCR）和蛋白质免疫印迹分析来寻找ANCR的靶基因。此外，我们使用RNA免疫沉淀（RIP）实验和染色质免疫沉淀实验来研究这种调控的分子机制。
我们发现ANCR在NPC组织和细胞中上调。ANCR表达与肿瘤大小和TNM分期显著相关。此外，敲低ANCR可抑制NPC细胞生长和辐射抗性。机制上，我们发现敲低ANCR的NPC细胞中磷酸酶和张力蛋白同源物（PTEN）上调。此外，RIP实验表明，多梳抑制复合物2的致癌组蛋白甲基转移酶EZH2在NPC细胞中与ANCR相互作用。更重要的是，EZH2与PTEN启动子上相关负性组蛋白标记H3K27me3的结合和沉积依赖于ANCR的表达。
ANCR在NPC中表达上调，并通过对PTEN表达的表观遗传调控促进NPC生长和辐射抗性。
