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Vasculogenic mimicry (VM) plays an important role in human glioma progression and resistance to antiangiogenic therapy as a compensatory neovascularization mechanism in malignant tumors. Caveolin-1 (Cav-1) has been found to contribute to VM formation. However, it remains largely unknown whether Cav-1 expression correlates with VM in glioma. In this study, we examined CAV-1 expression levels and VM in human glioma cell lines and in 94 human gliomas with different grades of malignancy, and present Cox proportional hazards regression. The molecular role of Cav-1 in glioma cells was investigated using quantitative polymerase chain reaction (qRT-PCR) assays, western blotting, CCK-8 assays, and tubule formation assays. Cav-1 expression and VM formation were positively correlated with each other and both were closely associated with glioma development and progression as evidenced by the presence of cystic tumor, shortened survival time, and advanced-stage glioma in glioma patients with Cav-1 overexpression/increased VM formation. Cav-1 promoted U251 glioma cell proliferation and VM formation in a Matrigel-based 3D culture model. VM-associated factors including hypoxia-inducible factor 1α (HIF-1α) and p-Akt was significantly elevated by Cav-1 overexpression but suppressed by siCav-1 in U251 cells. Collectively, our study identified Cav-1 as an important regulator of glioma cell proliferation and VM formation, contributing to glioma development and progression.

Objective: MicroRNAs (miRNAs) are a class of small noncoding RNAs that play important roles in tumor development and progression. miR-20a acts as an oncogene in many cancers; however, the underlying role of miR-20a in human glioma remains unknown., Methods: Glioma tissue samples were obtained from 32 patients with primary glioma who had undergone surgery at the First Affiliated Hospital of Sun Yat-sen University (Guangzhou, China). Twenty-two normal brain tissue samples used as controls were obtained by internal decompression in patients who had undergone surgery for cerebral injury and cerebral hemorrhage at the same hospital., Results: Quantitative reverse transcription polymerase chain reaction showed upregulation of miR-20a in glioma tissues and cell lines compared with normal brain tissue and normal human astrocytes. Functional assays showed that miR-20a promotes proliferation and invasion and inhibits apoptosis in glioma cells. The bioinformatic analysis showed that CELF2 (CUGBP Elav-like family member 2) is a direct target gene of miR-20a, which was confirmed using a luciferase reporter assay. Downregulation of CELF2 reversed the effects of inhibiting miR-20a expression., Conclusions: Collectively, these results suggest a critical role for miR-20a in glioma cell apoptosis, proliferation, and invasion via the direct targeting of CELF2 and indicate its potential application in cancer therapy., (Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.)