Tumor Biology

, Volume 36, Issue 6, pp 4271–4278 | Cite as

Stable knockdown of LRG1 by RNA interference inhibits growth and promotes apoptosis of glioblastoma cells in vitro and in vivo

  • Di Zhong
  • Siren Zhao
  • Guangxu He
  • Jinku Li
  • Yanbin Lang
  • Wei Ye
  • Yongli Li
  • Chuanlu Jiang
  • Xianfeng LiEmail author
Research Article


Leucine-rich α2 glycoprotein 1 (LRG1) has been shown to be aberrantly expressed in multiple human malignancies. However, the biological functions of LRG1 in human glioblastoma remain unknown. Here, we report for the first time the role of LRG1 in glioblastoma development based on the preliminary in vitro and in vivo data. We first confirmed the expression of LRG1 in human glioblastoma cell lines. Next, to investigate the role of LRG1 in the tumorigenesis and development of glioblastoma, a short hairpin RNA (shRNA) construct targeting LRG1 mRNA was transfected into U251 glioblastoma cells to generate a cell line with stably silenced LRG1 expression. The results showed that silencing of LRG1 significantly inhibited cell proliferation, induced cell cycle arrest at G0/G1 phase, and enhanced apoptosis in U251 cells in vitro. Consistently, LRG1 silencing resulted in the downregulation of key cell cycle factors including cyclin D1, B, and E and apoptotic gene Bcl-2 while elevated the levels of pro-apoptotic Bax and cleaved caspase-3, as determined by Western blot analysis. We further demonstrate that the silencing of LRG1 expression effectively reduced the tumorigenicity of U251 cells, delayed tumor formation, and promoted apoptosis in a xenograft tumor model in vivo. In conclusion, silencing the expression of LRG1 suppresses the growth of glioblastoma U251 cells in vitro and in vivo, suggesting that LRG1 may play a critical role in glioblastoma development, and it may have potential clinical implications in glioblastoma therapy.


LRG1 Glioblastoma Knockdown Proliferation Cell cycle Apoptosis 



This study was supported by a grant from the National Natural Science Foundation of China (No.: 30640008).


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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2015

Authors and Affiliations

  • Di Zhong
    • 1
  • Siren Zhao
    • 2
  • Guangxu He
    • 2
  • Jinku Li
    • 2
  • Yanbin Lang
    • 2
  • Wei Ye
    • 2
  • Yongli Li
    • 2
  • Chuanlu Jiang
    • 2
  • Xianfeng Li
    • 2
    Email author
  1. 1.Department of NeurologyThe First Affiliated Hospital of Harbin Medical UniversityHarbinChina
  2. 2.Department of NeurosurgeryThe Second Affiliated Hospital of Harbin Medical UniversityHarbinChina

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