Xiu Caimei, Song Ruiying, Jiang Jing
Department of Ophthalmology, the Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China.
Transl Cancer Res. 2021 Feb;10(2):738-747. doi: 10.21037/tcr-19-1480.
Retinoblastoma (RB), depicted as an aggressive eye cancer, mainly occurs in infancy and childhood and is followed by high mortality and poor prognosis. Increasing evidence has revealed that long noncoding RNA taurine upregulated gene 1 (TUG1) is closely linked to the progression of diverse cancers. Nonetheless, the specific function and molecular regulatory mechanism of TUG1 in RB still need to be explored.
To explore the specific role of TUG1 in RB. TUG1 expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell counting kit-8 (CCK-8), colony formation, 5-ethynyl-2'-deoxyuridine (EdU), caspase-3, terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) and western blot assays were utilized to study the role of TUG1 in RB. The binding relation between miR-516b-5p and TUG1 or hexose-6-phosphate dehydrogenase/glucose 1-dehydrogenase (H6PD) was analyzed by luciferase reporter and RNA immunoprecipitation (RIP) assays.
The expression of TUG1 was upregulated in RB cells. TUG1 knockdown repressed proliferation ability and promoted apoptosis ability of RB cells. Moreover, TUG1 could bind with miR-516b-5p, which targeted H6PD in RB. In addition, the expression of H6PD was negatively and positively regulated by miR-516b-5p and TUG1 in RB, respectively. Finally, H6PD overexpression could partially offset the effects of TUG1 deficiency on cell proliferation and apoptosis.
TUG1 promoted the development of RB by sponging miR-516b-5p to upregulate H6PD expression, which might provide a new thought for researching RB-related molecular mechanism.
视网膜母细胞瘤（RB）是一种侵袭性眼癌，主要发生于婴幼儿期，死亡率高且预后差。越来越多的证据表明，长链非编码RNA牛磺酸上调基因1（TUG1）与多种癌症的进展密切相关。然而，TUG1在RB中的具体功能和分子调控机制仍有待探索。
为探究TUG1在RB中的具体作用，采用实时定量聚合酶链反应（RT-qPCR）检测TUG1表达。运用细胞计数试剂盒-8（CCK-8）、集落形成、5-乙炔基-2'-脱氧尿苷（EdU）、半胱天冬酶-3、末端脱氧核苷酸转移酶介导的缺口末端标记（TUNEL）和蛋白质印迹分析等方法研究TUG1在RB中的作用。通过荧光素酶报告基因和RNA免疫沉淀（RIP）分析，检测微小RNA-516b-5p（miR-516b-5p）与TUG1或6-磷酸己糖脱氢酶/葡萄糖-1-脱氢酶（H6PD）之间的结合关系。
RB细胞中TUG1表达上调。敲低TUG1可抑制RB细胞的增殖能力并促进其凋亡能力。此外，TUG1可与miR-516b-5p结合，而miR-516b-5p在RB中靶向H6PD。另外，在RB中，H6PD的表达分别受到miR-516b-5p的负调控和TUG1的正调控。最后，H6PD过表达可部分抵消TUG1缺陷对细胞增殖和凋亡的影响。
TUG1通过吸附miR-516b-5p上调H6PD表达，从而促进RB的发展，这可能为研究RB相关分子机制提供新思路。
