Background. Glioma is one of the most aggressive and lethal human brain tumors. Accumulating evidence shows that microRNAs play important roles in cancers, including glioma. Previous studies reported that miR-124 levels were downregulated in glioma specimens. Here, we further investigate the potential role of miR-124 in glioma. Methods. The expression levels of miR-124 were detected in glioma specimens by quantitative reverse transcriptase PCR. The direct targets of miR-124 were identified by bioinformatics analysis and were further validated by immunoblotting and luciferase reporter assay. The effects of miR-124 on glioma cell proliferation and chemosensitivity to temozolomide were analyzed by Cell-Counting Kit 8 assay. Apoptosis was evaluated by fluorescence activated cell sorting analysis. A xenograft model was used to study the effect of miR-124 on tumor growth and angiogenesis. Results. Expression levels of miR-124 were greatly downregulated in glioma specimens. related Ras viral oncogene homolog (R-Ras) and neuroblastoma Ras viral oncogene homolog (N-Ras) were identified as direct targets of miR-124. MiR-124 inhibited glioma cell growth, invasion, angiogenesis, and tumor growth and increased chemosensitivity to temozolomide treatment by negatively regulating the Ras family and its downstream signaling pathways: phosphatidylinositol-3 kinase/Akt and Raf/extracellular signal-regulated kinase 1/2. Furthermore, overexpression of R-Ras rescued the inhibitory effects of miR-124. Meanwhile, overexpression of R-Ras and N-Ras restored miR-124-inhibited vascular endothelial growth factor (VEGF) transcription activation. In clinical glioma specimens, protein levels of R-Ras and N-Ras were upregulated and inversely correlated with miR-124 expression levels. Conclusions. Taken together, these results revealed that miR-124 levels in tumor tissues are associated with glioma occurrence, angiogenesis, and chemoresistance and that miR-124 may be used as a new diagnostic marker and therapeutic target for glioma in the future.
基金:
National Natural Science Foundation of ChinaNational Natural Science Foundation of China [81302182, 81372709, 81071642, 81302184, 81320108019, 30871296]; Jiangsu Province's Key Discipline of Medicine [XK201117]; National High Technology Research and Development Program 863National High Technology Research and Development Program of China [2012AA02A508]; Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD); National Institutes of HealthUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USA [R01ES020868]
第一作者机构:[1]Nanjing Med Univ, Affiliated Hosp 1, Dept Neurosurg, Nanjing 210029, Jiangsu, Peoples R China;[2]Nanjing Med Univ, State Key Lab Reprod Med, Dept Pathol, Nanjing, Peoples R China;[3]Nanjing Med Univ, Ctr Canc, Nanjing, Peoples R China;
通讯作者:
通讯机构:[1]Nanjing Med Univ, Affiliated Hosp 1, Dept Neurosurg, Nanjing 210029, Jiangsu, Peoples R China;[8]Nanjing Med Univ, Affiliated Hosp 1, Dept Neurosurg, 300 Guangzhou Rd, Nanjing 210029, Jiangsu, Peoples R China
推荐引用方式(GB/T 7714):
Shi Zhumei,Chen Qiudan,Li Chongyong,et al.MiR-124 governs glioma growth and angiogenesis and enhances chemosensitivity by targeting R-Ras and N-Ras[J].NEURO-ONCOLOGY.2014,16(10):1341-1353.doi:10.1093/neuonc/nou084.
APA:
Shi, Zhumei,Chen, Qiudan,Li, Chongyong,Wang, Lin,Qian, Xu...&Jiang, Bing-Hua.(2014).MiR-124 governs glioma growth and angiogenesis and enhances chemosensitivity by targeting R-Ras and N-Ras.NEURO-ONCOLOGY,16,(10)
MLA:
Shi, Zhumei,et al."MiR-124 governs glioma growth and angiogenesis and enhances chemosensitivity by targeting R-Ras and N-Ras".NEURO-ONCOLOGY 16..10(2014):1341-1353