2. Academic Validation
  3. FKBP9 promotes the malignant behavior of glioblastoma cells and confers resistance to endoplasmic reticulum stress inducers

FKBP9 promotes the malignant behavior of glioblastoma cells and confers resistance to endoplasmic reticulum stress inducers

  • J Exp Clin Cancer Res. 2020 Feb 28;39(1):44. doi: 10.1186/s13046-020-1541-0.
Huizhe Xu 1,  Peng Liu 2,  Yumei Yan 3,  Kun Fang 1,  Dapeng Liang 1,  Xiukun Hou 3,  Xiaohong Zhang 1,  Songyan Wu 1,  Jianmei Ma 4,  Ruoyu Wang 5,  Tao Li 6,  Haozhe Piao 7,  Songshu Meng 8
Affiliations

Affiliations

  • 1 Institute of Cancer Stem Cell, Dalian Medical University Cancer Center, 9 Lvshun Road South, Dalian, 116044, Liaoning Province, China.
  • 2 Department of General Surgery, Shenzhen University General Hospital, No. 1098, Xueyuan avenue, Shenzhen, 518055, China.
  • 3 The First Department of Ultrasound, The First Affiliated Hospital, Dalian Medical University, No. 222 Zhongshan Road, Dalian, 116021, Liaoning Province, China.
  • 4 Department of Anatomy, Dalian Medical University, 9 Lvshun Road South, Dalian, 116044, Liaoning Province, China.
  • 5 Department of Oncology, Affiliated Zhongshan Hospital of Dalian University, No.6 Jiefang Street, Dalian, 116001, Liaoning Province, China. [email protected].
  • 6 Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, No. 222 Zhongshan Road, Dalian, 116011, Liaoning Province, China. [email protected].
  • 7 Department of Neurosurgery, Cancer Hospital of China Medical University, Liaoning Cancer Hospital & Institute, No. 44 Xiaoheyan Road, Dadong District, Shenyang, 110042, Liaoning Province, China. [email protected].
  • 8 Institute of Cancer Stem Cell, Dalian Medical University Cancer Center, 9 Lvshun Road South, Dalian, 116044, Liaoning Province, China. [email protected].
PMID: 32111229 DOI: 10.1186/s13046-020-1541-0
Abstract

Background: FK506-binding protein 9 (FKBP9) is amplified in high-grade gliomas (HGGs). However, the roles and mechanism(s) of FKBP9 in glioma are unknown.

Methods: The expression of FKBP9 in clinical glioma tissues was detected by immunohistochemistry (IHC). The correlation between FKBP9 expression levels and the clinical prognosis of glioma patients was examined by bioinformatic analysis. Glioblastoma (GBM) cell lines stably depleted of FKBP9 were established using lentiviruses expressing shRNAs against FKBP9. The effects of FKBP9 on GBM cells were determined by cell-based analyses, including anchorage-independent growth, spheroid formation, transwell invasion assay, confocal microscopy, immunoblot (IB) and coimmunoprecipitation assays. In vivo tumor growth was determined in both chick chorioallantoic membrane (CAM) and mouse xenograft models.

Results: High FKBP9 expression correlated with poor prognosis in glioma patients. Knockdown of FKBP9 markedly suppressed the malignant phenotype of GBM cells in vitro and inhibited tumor growth in vivo. Mechanistically, FKBP9 expression induced the activation of p38MAPK signaling via ASK1. Furthermore, ASK1-p38 signaling contributed to the FKBP9-mediated effects on GBM cell clonogenic growth. In addition, depletion of FKBP9 activated the IRE1α-XBP1 pathway, which played a role in the FKBP9-mediated oncogenic effects. Importantly, FKBP9 expression conferred GBM cell resistance to endoplasmic reticulum (ER) stress inducers that caused FKBP9 ubiquitination and degradation.

Conclusions: Our findings suggest an oncogenic role for FKBP9 in GBM and reveal FKBP9 as a novel mediator in the IRE1α-XBP1 pathway.

Keywords

Endoplasmic reticulum (ER) stress; FK506-binding protein 9; Glioma; IRE1α-XBP1; Unfolded protein response (UPR).

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