title: MiR-124 governs glioma growth and angiogenesis and enhances chemosensitivity by targeting R-Ras and N-Ras.
abstract: 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.
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Zhumei
authors.initials: Z
authors.lastname: Shi
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Qiudan
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Chongyong
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Xu
authors.initials: X
authors.lastname: Qian
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Chengfei
authors.initials: C
authors.lastname: Jiang
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Xue
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Xiefeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Hai
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Kang
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Tao
authors.initials: T
authors.lastname: Jiang
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Ling-Zhi
authors.initials: LZ
authors.lastname: Liu
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Yongping
authors.initials: Y
authors.lastname: You
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (Z.S., X.W., Y.Y., N.L.); State Key Lab of Reproductive Medicine, Department of Pathology, and Cancer Center, Nanjing Medical University, Nanjing, China (Z.S., Q.C., C.L., L.W., X.Q., C.J., X.L., B.-H.J.); Department of Pathology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (H.L.); Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China (C.K.); Department of Neurosurgery, Tiantan Hospital, Capital Medical University, Beijing, China (T.J.); Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (L.-Z.L., B.-H.J.).
authors.forename: Bing-Hua
authors.initials: BH
authors.lastname: Jiang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001921:Brain / Q000098:blood supply; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003606:Dacarbazine / Q000008:administration & dosage / Q000031:analogs & derivatives; D011905:Genes, ras; D005910:Glioma / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D035683:MicroRNAs / Q000378:metabolism*; D009361:Neoplasm Invasiveness / Q000503:physiopathology; D009389:Neovascularization, Pathologic; D015398:Signal Transduction; D000077204:Temozolomide; D018631:ras Proteins / Q000378:metabolism*
chemical_list: C509207:MIRN124 microRNA, human; D035683:MicroRNAs; D003606:Dacarbazine; C085929:RRAS protein, human; D018631:ras Proteins; D000077204:Temozolomide
keywords: N-Ras; R-Ras; carcinogenesis; glioma; miR-124