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Updated: May 26, 2026

Quantitative Immunohistochemistry of the Cellular Microenvironment in Patient Glioblastoma Resections
05:45

Quantitative Immunohistochemistry of the Cellular Microenvironment in Patient Glioblastoma Resections

Published on: July 31, 2017

Serine/threonine protein phosphatase 6 modulates the radiation sensitivity of glioblastoma

Y Shen1, Y Wang, K Sheng

  • 1Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Institute of Medical Science, Shanghai JiaoTong University School of Medicine, Shanghai, China.

Cell Death & Disease
|December 14, 2011
PubMed

Insights

Protein phosphatase 6 (PP6) regulates glioblastoma (GBM) cell sensitivity to radiation. Inhibiting PP6 may enhance radiation therapy effectiveness and improve patient survival in GBM treatment.

Area of Science:

  • Oncology
  • Molecular Biology
  • Radiotherapy Research

Background:

  • Glioblastoma multiforme (GBM) presents a significant challenge in cancer treatment.
  • Enhancing GBM cell sensitivity to radiation is a key strategy for improving patient outcomes.
  • Identifying novel molecular targets for radiosensitization is crucial for advancing GBM therapy.

Purpose of the Study:

  • To investigate the role of serine/threonine phosphatase (protein phosphatase 6 (PP6)) as a molecular target for GBM radiosensitization.
  • To determine the correlation between PP6 expression levels and GBM cell radiosensitivity and patient survival.

Main Methods:

  • Utilized a GBM orthotopic xenograft mice model.
  • Assessed PP6 catalytic subunit (PP6c) protein levels in patient GBM tissue.
  • Examined the effect of PP6c knockdown and overexpression on GBM cell radiosensitivity in vitro and in vivo.
  • Measured DNA-dependent protein kinase (DNA-PK) activity following PP6c modulation.

Main Results:

  • PP6c protein levels were upregulated in approximately 50% of GBM patient tissues.
  • PP6c expression inversely correlated with patient survival time and GBM cell survival fraction.
  • siRNA knockdown of PP6c reduced DNA-PK activity and increased GBM cell radiosensitivity.
  • In vivo studies showed PP6c overexpression attenuated radiation effects, while knockdown enhanced them, impacting mouse survival.

Conclusions:

  • PP6 plays a significant role in regulating GBM cell sensitivity to radiation therapy.
  • Targeting the PP6-DNA-PK interaction with small molecules represents a potential radiosensitizing strategy for GBM treatment.

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