Wang Zheng, Wang Xiaoxi, Cheng Fei, Wen Xue, Feng Shi, Yu Fang, Tang Hui, Liu Zhengjin, Teng Xiaodong
Department of Neurology, Hangzhou Seventh People's Hospital, Hangzhou, People's Republic of China.
Department of Pathology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People's Republic of China.
Cancer Manag Res. 2021 Mar 22;13:2691-2700. doi: 10.2147/CMAR.S298468. eCollection 2021.
Glioma is a common intracranial malignant tumor with high rates of invasiveness and mortality. This study aimed to investigate the mechanism of rapamycin in glioma.
U118-MG cells were treated with and without rapamycin in vivo and then collected for RNA sequencing. Differentially expressed miRNAs (DEMs) were screened and verified. MiR-26a-5p was selected for functional verification, and the target gene of miR-26a-5p was identified. The effects of miR-26a-5p on cell proliferation, cell cycle, apoptosis, and autophagy were also investigated.
In total, 58 up-regulated and 41 down-regulated DEMs were identified between rapamycin-treated and untreated U118-MG cells. MiR-26-5p levels were up-regulated in U118-MG cells treated with 12.5 μM rapamycin, and death-associated protein kinase 1 (DAPK1) expression, a direct miR-26a-5p target gene, was down-regulated. Rapamycin substantially inhibited cell proliferation and cell percentage in the S phase and promoted cell apoptosis; miR-26a-5p inhibitor increased cell proliferation and cell cycle and decreased cell apoptosis; DAPK1 overexpression further induced cell proliferation, increased the cell number in the S phase, and inhibited apoptosis in glioma cells. Notably, rapamycin increased the autophagy-related Beclin1 protein expression levels and the LC3 II/I ratio.
Rapamycin exerts anti-tumor effects by promoting autophagy in glioma cells, which was dependent on the miR-26a-5p/DAPK1 pathway activation by rapamycin.
胶质瘤是一种常见的颅内恶性肿瘤，具有较高的侵袭性和死亡率。本研究旨在探讨雷帕霉素在胶质瘤中的作用机制。
将U118-MG细胞在体内分别用雷帕霉素处理和不处理，然后收集细胞进行RNA测序。筛选并验证差异表达的miRNA（DEM）。选择miR-26a-5p进行功能验证，并鉴定miR-26a-5p的靶基因。还研究了miR-26a-5p对细胞增殖、细胞周期、凋亡和自噬的影响。
在雷帕霉素处理和未处理的U118-MG细胞之间，共鉴定出58个上调和41个下调的DEM。在用12.5μM雷帕霉素处理的U118-MG细胞中，miR-26-5p水平上调，而直接的miR-26a-5p靶基因死亡相关蛋白激酶1（DAPK1）的表达下调。雷帕霉素显著抑制细胞增殖和S期细胞百分比，并促进细胞凋亡；miR-26a-5p抑制剂增加细胞增殖和细胞周期，并减少细胞凋亡；DAPK1过表达进一步诱导细胞增殖，增加S期细胞数量，并抑制胶质瘤细胞凋亡。值得注意的是，雷帕霉素增加了自噬相关的Beclin1蛋白表达水平和LC3 II/I比率。
雷帕霉素通过促进胶质瘤细胞的自噬发挥抗肿瘤作用，这依赖于雷帕霉素激活的miR-26a-5p/DAPK1途径。
