Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004, People׳s Republic of China.
Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001, People׳s Republic of China; Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001, People׳s Republic of China.
Exp Cell Res. 2014 May 15;324(1):54-64. doi: 10.1016/j.yexcr.2014.03.009. Epub 2014 Mar 21.
MiR-17-92 cluster has recently been reported as an oncogene in some tumors. However, the association of miR-18a, an important member of this cluster, with glioblastoma remains unknown. Therefore, this study aims to investigate the expression of miR-18a in glioblastoma and its role in biological behavior of U87 and U251 human glioblastoma cell lines. Quantitative RT-PCR results showed that miR-18a was highly expressed in glioblastoma tissues and U87 and U251 cell lines compared with that in human brain tissues and primary normal human astrocytes, and the expression levels were increased along with the rising pathological grades of glioblastoma. Neogenin was identified as the target gene of miR-18a by dual-luciferase reporter assays. RT-PCR and western blot results showed that its expression levels were decreased along with the rising pathological grades of glioblastoma. Inhibition of miR-18a expression was established by transfecting exogenous miR-18a inhibitor into U87 and U251 cells, and its effects on the biological behavior of glioblastoma cells were studied using CCK-8 assay, transwell assay and flow cytometry. Inhibition of miR-18a expression in U87 and U251 cells significantly up-regulated neogenin, and dramatically suppressed the abilities of cell proliferation, migration and invasion, induced cell cycle arrest and promoted cellular apoptosis. Collectively, these results suggest that miR-18a may regulate biological behavior of human glioblastoma cells by targeting neogenin, and miR-18a can serve as a potential target in the treatment of glioblastoma.
miR-17-92 簇最近被报道为一些肿瘤中的癌基因。然而，miR-18a 作为该簇的一个重要成员，与神经胶质瘤的关系尚不清楚。因此，本研究旨在探讨 miR-18a 在神经胶质瘤中的表达及其在 U87 和 U251 人神经胶质瘤细胞系中的生物学行为中的作用。定量 RT-PCR 结果显示，与正常人脑组织和原代正常星形胶质细胞相比，miR-18a 在神经胶质瘤组织和 U87、U251 细胞系中高表达，且表达水平随神经胶质瘤病理分级的升高而升高。双荧光素酶报告基因实验鉴定出 neogenin 是 miR-18a 的靶基因。RT-PCR 和 Western blot 结果显示，其表达水平随神经胶质瘤病理分级的升高而降低。通过转染外源性 miR-18a 抑制剂建立 miR-18a 表达抑制，用 CCK-8 检测、Transwell 检测和流式细胞术研究其对神经胶质瘤细胞生物学行为的影响。抑制 U87 和 U251 细胞中 miR-18a 的表达显著上调了 neogenin，显著抑制了细胞增殖、迁移和侵袭能力，诱导细胞周期停滞，并促进细胞凋亡。综上所述，这些结果表明，miR-18a 可能通过靶向 neogenin 调节人神经胶质瘤细胞的生物学行为，miR-18a 可作为神经胶质瘤治疗的潜在靶点。
