Zhao Long, Tang Xiaoping, Luo Renguo, Duan Jie, Wang Yuanchuan, Yang Binbin
Department of Neurosurgery, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China.
Curr Neurovasc Res. 2018;15(3):246-255. doi: 10.2174/1567202615666180813130143.
Glioma is a type of tumor that starts in the glial cells of brain and spine. However, the underlying molecular mechanisms of miRNAs dysregulation in glioma initiation and progression is largely unclear.
To further understand the molecular mechanism of miR-490-5P functions and how miR-490 regulated CCND1 function.
The expression of miR-490-5P in glioma tissues and cells was measured by qRT-PCR and ISH. Cell transfection is responsible for miR-490-5P overexpression and knockdown. CCK-8 and clone formation assay are applicable to examine the capacity of glioma cells proliferation. Cell cycle analysis is used to test glioma cells cycle distribution with miR-490-5P overexpression or downregulation. Further, in vivo tumor exnograft studies are used to examine the effects of miR- 490-5P on glioma malignancy in vivo.
We found overexpression of miR-490 lead to glioma cells cycle arrest at G1 phase and decreased proliferation. Next-step functional assays showed miR-490 regulated CCND1 expression and manipulated giloma cells proliferation. Finally, negative regulation of miR-490 in CCND1 function was validated through in vivo nude mice tumorigenesis assay and IHC examination in glioma tissue.
Overall, these results showed that epigenetic regulation of CCND1 via miR-490 was essential to glioma and provide a new insight into glioma diagnosis, treatment, prognosis and further translational investigations.
胶质瘤是一种起源于脑和脊髓神经胶质细胞的肿瘤。然而,微小RNA(miRNA)失调在胶质瘤起始和进展中的潜在分子机制在很大程度上尚不清楚。
进一步了解miR-490-5P的功能分子机制以及miR-490如何调节细胞周期蛋白D1(CCND1)的功能。
采用实时定量逆转录聚合酶链反应(qRT-PCR)和原位杂交(ISH)检测胶质瘤组织和细胞中miR-490-5P的表达。通过细胞转染实现miR-490-5P的过表达和敲低。采用细胞计数试剂盒-8(CCK-8)和克隆形成试验检测胶质瘤细胞的增殖能力。利用细胞周期分析检测过表达或下调miR-490-5P时胶质瘤细胞的周期分布。此外,通过体内肿瘤异种移植研究检测miR-490-5P对体内胶质瘤恶性程度的影响。
我们发现miR-490过表达导致胶质瘤细胞在G1期发生细胞周期阻滞并降低增殖能力。下一步功能试验表明,miR-490调节CCND1的表达并调控胶质瘤细胞的增殖。最后,通过体内裸鼠肿瘤发生试验和胶质瘤组织的免疫组化检查验证了miR-490对CCND1功能具有负调控作用。
总体而言,这些结果表明,miR-490对CCND1的表观遗传调控对胶质瘤至关重要,并为胶质瘤的诊断、治疗、预后及进一步的转化研究提供了新的见解。