Oncoprotein Bmi-1 renders apoptotic resistance to glioma cells through activation of the IKK-nuclear factor-kappaB

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Updated: Jun 17, 2026

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

Jun Li1, Li-Yun Gong, Li-Bing Song

  • 1Departments of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University, 74 Zhongshan Road II, Guangzhou, Guangdong 510080, China.

The American Journal of Pathology
|December 26, 2009
PubMed

Insights

Bmi-1 oncoprotein confers resistance to apoptosis in glioma cells by activating the nuclear factor-kappaB (NF-kappaB) pathway. This mechanism highlights Bmi-1 as a potential prognostic marker for glioma progression and patient survival.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cancer Research

Background:

  • Malignant gliomas exhibit resistance to apoptosis, a key factor in treatment failure.
  • The oncoprotein Bmi-1 is implicated in oncogenesis and cancer progression, but its antiapoptotic mechanisms in gliomas are unclear.

Purpose of the Study:

  • To elucidate the role of Bmi-1 in mediating apoptotic resistance in glioma cells.
  • To investigate the involvement of the nuclear factor-kappaB (NF-kappaB) pathway in Bmi-1's antiapoptotic function.

Main Methods:

  • Ectopic expression and depletion of Bmi-1 in glioma cells.
  • Assessment of apoptosis markers (caspase-3, PARP, Bcl-X(L)).
  • Analysis of NF-kappaB pathway activation (IKK, IkappaB phosphorylation, nuclear translocation).

Main Results:

  • Bmi-1 overexpression inhibited apoptosis induced by doxorubicin, BCNU, or UV irradiation.
  • Bmi-1 depletion sensitized glioma cells to apoptosis.
  • Bmi-1 activated the IKK-NF-kappaB pathway, leading to downstream gene expression.
  • Inhibition of the IKK-NF-kappaB pathway abolished Bmi-1's antiapoptotic effect.
  • Bmi-1 and NF-kappaB were co-expressed in high-grade gliomas and correlated with poor survival.

Conclusions:

  • Bmi-1 confers apoptotic resistance in glioma cells via the IKK-NF-kappaB pathway.
  • Bmi-1 is a potential prognostic indicator for glioma patients.

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