Downregulation of Pygopus 2 inhibits vascular mimicry in glioma U251 cells by suppressing the canonical Wnt signaling pathway

Wang,Haidong; Fu,Jianhua; Xu,Dianshuang; Xu,Weiwei; Wang,Shiyong; Zhang,Liu; Xiang,Yongsheng

doi:10.3892/ol.2015.3917

Downregulation of Pygopus 2 inhibits vascular mimicry in glioma U251 cells by suppressing the canonical Wnt signaling pathway

Authors:
- Haidong Wang
- Jianhua Fu
- Dianshuang Xu
- Weiwei Xu
- Shiyong Wang
- Liu Zhang
- Yongsheng Xiang
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Affiliations: Department of Neurosurgery, Affiliated First Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China, Department of Neurosurgery, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 580001, P.R. China
Published online on: November 13, 2015 https://doi.org/10.3892/ol.2015.3917
Pages: 678-684

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Abstract

Gliomas are the most common type of malignant primary brain tumor, and the Wnt signaling pathway is associated with glioma malignancy. Pygopus protein plays an important role in developmental brain patterning, and has been identified to be a component of the Wnt signaling pathway. In the present study, the Pygopus 2 (Pygo2) protein was examined in 80 glioma tissue samples. Short hairpin (sh)RNA‑Pygo2 was transfected into glioma U251 cells, and the cell proliferation, colony formation and bromodeoxyuridine (BrdU) incorporation were analyzed. Western blot analysis and reverse transcription‑polymerase chain reaction were used to detect the expression of Pygo2. A vascular mimicry assay was performed to examine the vascular mimicry of U251 cells. A luciferase reporter assay was used to detect the β‑catenin/Wnt system. The cyclin D1 protein was also detected using western blot analysis. The results demonstrated that inhibition of the expression of Pygo2 significantly triggered the decrease of cell proliferation, colony formation and BrdU incorporation compared with the cells treated with scramble control shRNA (shRNA‑Scr). shRNA‑Pygo2 transfection was found to inhibit vascular‑mimicry and block the Wnt signaling pathway compared to the cells transfected with shRNA‑Scr. The transfection of shRNA‑Pygo2 also decreased the expression of the Wnt target gene cyclin D1. In conclusion, shRNA‑Pygo2 suppressed glioma cell proliferation effectively and inhibited vascular mimicry by inhibiting the expression of cyclin D1 in the canonical Wnt/β‑catenin pathway in brain glioma cells.

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