Xiong Zhiyong, Wang Luyang, Wang Qiangping, Yuan Ye
Department of Neurosurgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Department of Neurology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
J Cell Mol Med. 2018 Aug;22(8):3929-3940. doi: 10.1111/jcmm.13667. Epub 2018 May 29.
We aimed to explore the interaction among lncRNA MALAT1, miR-129 and SOX2. Besides, we would investigate the effect of MALAT1 on the proliferation of glioma stem cells and glioma tumorigenesis. Differentially expressed lncRNAs in glioma cells and glioma stem cells were screened out with microarray analysis. The targeting relationship between miR-129 and MALAT1 or SOX2 was validated by dual-luciferase reporter assay. The expressions of MALAT1, miR-129 and SOX2mRNA in both glioma non-stem cells and glioma stem cells were examined by qRT-PCR assay. The impact of MALAT1 and miR-129 on glioma stem cell proliferation was observed by CCK-8 assay, EdU assay and sphere formation assay. The protein expression of SOX2 was determined by western blot. The effects of MALAT1 and miR-129 on glioma tumour growth were further confirmed using xenograft mouse model. The mRNA expression of MALAT1 was significantly up-regulated in glioma stem cells compared with non-stem cells, while miR-129 was significantly down-regulated in glioma stem cells. MALAT1 knockdown inhibited glioma stem cell proliferation via miR-129 enhancement. Meanwhile, miR-129 directly targeted at SOX2 and suppressed cell viability and proliferation of glioma stem cells by suppressing SOX2 expression. The down-regulation of MALAT1 and miR-129 overexpression both suppressed glioma tumour growth via SOX2 expression promotion in vivo. MALAT1 enhanced glioma stem cell viability and proliferation abilities and promoted glioma tumorigenesis through suppressing miR-129 and facilitating SOX2 expressions.
我们旨在探究长链非编码RNA MALAT1、miR-129和SOX2之间的相互作用。此外，我们将研究MALAT1对胶质瘤干细胞增殖及胶质瘤肿瘤发生的影响。通过微阵列分析筛选出胶质瘤细胞和胶质瘤干细胞中差异表达的长链非编码RNA。采用双荧光素酶报告基因检测法验证miR-129与MALAT1或SOX2之间的靶向关系。运用qRT-PCR检测法检测MALAT1、miR-129和SOX2mRNA在胶质瘤非干细胞和胶质瘤干细胞中的表达情况。通过CCK-8检测法、EdU检测法和球体形成检测法观察MALAT1和miR-129对胶质瘤干细胞增殖的影响。采用蛋白质免疫印迹法测定SOX2的蛋白表达。利用异种移植小鼠模型进一步证实MALAT1和miR-129对胶质瘤肿瘤生长的影响。与非干细胞相比，MALAT1的mRNA表达在胶质瘤干细胞中显著上调，而miR-129在胶质瘤干细胞中显著下调。敲低MALAT1通过增强miR-129抑制胶质瘤干细胞增殖。同时，miR-129直接靶向SOX2，并通过抑制SOX2表达抑制胶质瘤干细胞的活力和增殖。在体内，MALAT1的下调和miR-129的过表达均通过促进SOX2表达抑制胶质瘤肿瘤生长。MALAT1通过抑制miR-129并促进SOX2表达增强胶质瘤干细胞的活力和增殖能力，促进胶质瘤肿瘤发生。
