Data_Sheet_2_RETRACTED: Long Non-coding RNA LINC00320 Inhibits Tumorigenicity of Glioma Cells and Angiogenesis Through Downregulation of NFKB1-Mediated AQP9.ZIP

The inhibitory effect of long intergenic non-coding RNA 00320 (LINC00320) in glioma cell proliferation has been proposed in a recent study. However, the mechanisms by which LINC00320 regulate aquaporin 9 (AQP9) in glioma require further exploration. Hence, this study aims to investigate effects of LINC00320 on tumorigenicity of glioma cells and angiogenesis of microvascular endothelial cells (MVECs). Expression of LINC00320 and AQP9 in glioma tissues and cells was measured by reverse transcription–quantitative polymerase chain reaction and Western blot analysis. The relationship among LINC00320, nuclear factor κB subunit 1 (NFKB1) and AQP9 was examined by RNA immunoprecipitation, dual-luciferase reporter gene, and chromatin immunoprecipitation assays. The participation of LINC00320 and AQP9 in glioma cell proliferation and MVEC angiogenesis was analyzed using gain- and loss-of-function approaches. Finally, a nude mouse orthotopic xenograft model of glioma was established to investigate the effects of LINC00320 and AQP9 on glioma growth in vivo. LINC00320 was under-expressed and AQP9 was over-expressed in glioma tissues. Further mechanistic investigation showed that LINC00320 downregulated AQP9 by inhibiting the recruitment of NFKB1 to the promoter region of AQP9. LINC00320 overexpression or AQP9 silencing inhibited the proliferation of glioma cells and angiogenesis of MVECs. Also, upregulation of LINC00320 restrained tumor growth and angiogenesis in xenograft mice by downregulating AQP9. Taken together, LINC00320 acts as a tumor suppressor in glioma, thus presenting a novel therapeutic target.

近期研究提出了长链非编码RNA 00320（LINC00320）对胶质瘤细胞增殖的抑制作用。然而，LINC00320调控胶质瘤中水通道蛋白9（AQP9）的机制尚需进一步探究。因此，本研究旨在调查LINC00320对胶质瘤细胞的肿瘤生成性和微血管内皮细胞（MVECs）血管生成的影响。通过逆转录-定量聚合酶链反应和蛋白质印迹分析，对胶质瘤组织和细胞中的LINC00320和AQP9的表达进行了测定。通过RNA免疫沉淀、双荧光素酶报告基因和染色质免疫沉淀实验，考察了LINC00320、核因子κB亚基1（NFKB1）和AQP9之间的关系。利用功能获得和功能丧失方法分析了LINC00320和AQP9在胶质瘤细胞增殖和MVEC血管生成中的作用。最终，建立了一种裸鼠原位异种移植模型，以研究LINC00320和AQP9对胶质瘤体内生长的影响。结果显示，LINC00320在胶质瘤组织中表达下调，而AQP9表达上调。进一步的机制研究表明，LINC00320通过抑制NFKB1招募至AQP9启动子区域来下调AQP9。LINC00320过表达或AQP9沉默抑制了胶质瘤细胞的增殖和MVEC的血管生成。此外，LINC00320的上调通过下调AQP9抑制了异种移植小鼠的肿瘤生长和血管生成。综上所述，LINC00320在胶质瘤中作为肿瘤抑制因子发挥作用，从而呈现了一种新的治疗靶点。