Xu Ran, Zhu Xuan, Chen Fangzhi, Huang Changkun, Ai Kai, Wu Hongtao, Zhang Lei, Zhao Xiaokun
Department of Urology, The Second Xiangya Hospital, Central South University, Middle Renmin Road No. 139, Changsha, 410011 Hunan China.
Cancer Cell Int. 2018 Mar 20;18:41. doi: 10.1186/s12935-018-0540-0. eCollection 2018.
The abnormal expression of non-coding RNAs (ncRNAs), such as microRNAs and long ncRNAs, often contribute to the development of cancers. miR-200c functions as a tumour suppressor that impacts the growth of bladder cancer cells and the epithelial-to-mesenchymal transition (EMT). LncRNA X inactive specific transcript (XIST) is highly expressed in tumour tissues, promotes cancer progression and might act as an miRNA molecular sponge. This study aimed to examine the relationship between lncRNA XIST and miR-200c and to assess their functions in the regulation of the stemness properties and tumourigenicity of human bladder cancer stem cell (BCSC)-like cells.
Biological effects including cell clone formation, sphere formation, self-renewal properties and mouse tumourigenesis were examined in BCSC-like cells with miR-200c overexpression or XIST knockdown. Real-time PCR and western blotting were used to detect the expression changing of related factors in BCSC-like cells gene models. Dual luciferase reporter assay was used to examine the changes of XIST and miR-200c expression levels.
The results indicated that miR-200c overexpression and XIST knockdown could inhibit cell clone formation, self-renewal ability and EMT in BCSC-like cells. miR-200c knockdown could restore the tumour growth inhibition caused by XIST knockdown.
LncRNA XIST may act as an inhibitor of miR-200c to regulate the stemness properties and tumourigenicity of bladder cancer cells, and our findings might reveal a potential strategy of targeting XIST for bladder cancer therapy.
非编码RNA（ncRNA），如微小RNA和长链ncRNA的异常表达，常常促成癌症的发展。miR-200c作为一种肿瘤抑制因子，影响膀胱癌细胞的生长以及上皮-间质转化（EMT）。长链ncRNA X染色体失活特异性转录本（XIST）在肿瘤组织中高表达，促进癌症进展，可能作为一种微小RNA分子海绵发挥作用。本研究旨在探究长链ncRNA XIST与miR-200c之间的关系，并评估它们在调控人膀胱癌干细胞（BCSC）样细胞的干性特性和致瘤性中的作用。
在过表达miR-200c或敲低XIST的BCSC样细胞中检测细胞克隆形成、成球、自我更新特性和小鼠致瘤性等生物学效应。采用实时定量PCR和蛋白质免疫印迹法检测BCSC样细胞基因模型中相关因子的表达变化。采用双荧光素酶报告基因检测法检测XIST和miR-200c表达水平的变化。
结果表明，过表达miR-200c和敲低XIST可抑制BCSC样细胞的克隆形成、自我更新能力和EMT。敲低miR-200c可恢复敲低XIST所导致的肿瘤生长抑制。
长链ncRNA XIST可能作为miR-200c的抑制剂来调控膀胱癌细胞的干性特性和致瘤性，我们的研究结果可能揭示了一种针对XIST进行膀胱癌治疗的潜在策略。
