Activation of WEE1 confers resistance to PI3K inhibition in glioblastoma

Shaofang Wu, Shuzhen Wang, Feng Gao, Luyuan Li, Siyuan Zheng, W. K.Alfred Yung, DImpy Koul

Research output: Contribution to journalArticle

  • 2 Citations

Abstract

Background Oncogenic activation of phosphatidylinositol-3 kinase (PI3K) signaling plays a pivotal role in the development of glioblastoma (GBM). However, pharmacological inhibition of PI3K has so far not been therapeutically successful due to adaptive resistance through a rapid rewiring of cancer cell signaling. Here we identified that WEE1 is activated after transient exposure to PI3K inhibition and confers resistance to PI3K inhibition in GBM. Methods Patient-derived glioma-initiating cells and established GBM cells were treated with PI3K inhibitor or WEE1 inhibitor alone or in combination, and cell proliferation was evaluated by CellTiter-Blue assay. Cell apoptosis was analyzed by TUNEL, annexin V staining, and blotting of cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase. Both subcutaneous xenograft and orthotropic xenograft studies were conducted to evaluate the effects of the combination on tumorigenesis; the tumor growth was monitored by bioluminescence imaging, and tumor tissue was analyzed by immunohistochemistry to validate signaling changes. Results PI3K inhibition activates WEE1 kinase, which in turn phosphorylates cell division control protein 2 homolog (Cdc2) at Tyr15 and inhibits Cdc2 activity, leading to G2/M arrest in a p53-independent manner. WEE1 inhibition abrogated the G2/M arrest and propelled cells to prematurely enter into mitosis and consequent cell death through mitotic catastrophe and apoptosis. Additionally, combination treatment significantly suppressed tumor growth in a subcutaneous model but not in an intracranial model due to limited blood-brain barrier penetration. Conclusions Our findings highlight WEE1 as an adaptive resistant gene activated after PI3K inhibition, and inhibition of WEE1 potentiated the effectiveness of PI3K targeted inhibition, suggesting that a combinational inhibition of WEE1 and PI3K might allow successful targeted therapy in GBM.

LanguageEnglish (US)
Pages78-91
Number of pages14
JournalNeuro-Oncology
Volume20
Issue number1
DOIs
StatePublished - Jan 1 2018
Externally publishedYes

Fingerprint

Phosphatidylinositol 3-Kinase
Glioblastoma
Heterografts
Cell Division
Neoplasms
Apoptosis
Poly(ADP-ribose) Polymerases
Annexin A5
In Situ Nick-End Labeling
Growth
Blood-Brain Barrier
Mitosis
Glioma
Caspase 3
Carcinogenesis
Proteins
Cell Death
Phosphotransferases
Immunohistochemistry
Cell Proliferation

Keywords

  • mitotic catastrophic cell death
  • PI3K inhibition resistance
  • WEE1

ASJC Scopus subject areas

  • Oncology
  • Clinical Neurology
  • Cancer Research

Cite this

Activation of WEE1 confers resistance to PI3K inhibition in glioblastoma. / Wu, Shaofang; Wang, Shuzhen; Gao, Feng; Li, Luyuan; Zheng, Siyuan; Yung, W. K.Alfred; Koul, DImpy.

In: Neuro-Oncology, Vol. 20, No. 1, 01.01.2018, p. 78-91.

Research output: Contribution to journalArticle

Wu, S, Wang, S, Gao, F, Li, L, Zheng, S, Yung, WKA & Koul, DI 2018, 'Activation of WEE1 confers resistance to PI3K inhibition in glioblastoma' Neuro-Oncology, vol. 20, no. 1, pp. 78-91. https://doi.org/10.1093/neuonc/nox128
Wu, Shaofang ; Wang, Shuzhen ; Gao, Feng ; Li, Luyuan ; Zheng, Siyuan ; Yung, W. K.Alfred ; Koul, DImpy. / Activation of WEE1 confers resistance to PI3K inhibition in glioblastoma. In: Neuro-Oncology. 2018 ; Vol. 20, No. 1. pp. 78-91.
@article{1ddef17625c243f89ee9df92e8d59441,
title = "Activation of WEE1 confers resistance to PI3K inhibition in glioblastoma",
abstract = "Background Oncogenic activation of phosphatidylinositol-3 kinase (PI3K) signaling plays a pivotal role in the development of glioblastoma (GBM). However, pharmacological inhibition of PI3K has so far not been therapeutically successful due to adaptive resistance through a rapid rewiring of cancer cell signaling. Here we identified that WEE1 is activated after transient exposure to PI3K inhibition and confers resistance to PI3K inhibition in GBM. Methods Patient-derived glioma-initiating cells and established GBM cells were treated with PI3K inhibitor or WEE1 inhibitor alone or in combination, and cell proliferation was evaluated by CellTiter-Blue assay. Cell apoptosis was analyzed by TUNEL, annexin V staining, and blotting of cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase. Both subcutaneous xenograft and orthotropic xenograft studies were conducted to evaluate the effects of the combination on tumorigenesis; the tumor growth was monitored by bioluminescence imaging, and tumor tissue was analyzed by immunohistochemistry to validate signaling changes. Results PI3K inhibition activates WEE1 kinase, which in turn phosphorylates cell division control protein 2 homolog (Cdc2) at Tyr15 and inhibits Cdc2 activity, leading to G2/M arrest in a p53-independent manner. WEE1 inhibition abrogated the G2/M arrest and propelled cells to prematurely enter into mitosis and consequent cell death through mitotic catastrophe and apoptosis. Additionally, combination treatment significantly suppressed tumor growth in a subcutaneous model but not in an intracranial model due to limited blood-brain barrier penetration. Conclusions Our findings highlight WEE1 as an adaptive resistant gene activated after PI3K inhibition, and inhibition of WEE1 potentiated the effectiveness of PI3K targeted inhibition, suggesting that a combinational inhibition of WEE1 and PI3K might allow successful targeted therapy in GBM.",
keywords = "mitotic catastrophic cell death, PI3K inhibition resistance, WEE1",
author = "Shaofang Wu and Shuzhen Wang and Feng Gao and Luyuan Li and Siyuan Zheng and Yung, {W. K.Alfred} and DImpy Koul",
year = "2018",
month = "1",
day = "1",
doi = "10.1093/neuonc/nox128",
language = "English (US)",
volume = "20",
pages = "78--91",
journal = "Neuro-Oncology",
issn = "1522-8517",
publisher = "Oxford University Press",
number = "1",

}

TY - JOUR

T1 - Activation of WEE1 confers resistance to PI3K inhibition in glioblastoma

AU - Wu, Shaofang

AU - Wang, Shuzhen

AU - Gao, Feng

AU - Li, Luyuan

AU - Zheng, Siyuan

AU - Yung, W. K.Alfred

AU - Koul, DImpy

PY - 2018/1/1

Y1 - 2018/1/1

N2 - Background Oncogenic activation of phosphatidylinositol-3 kinase (PI3K) signaling plays a pivotal role in the development of glioblastoma (GBM). However, pharmacological inhibition of PI3K has so far not been therapeutically successful due to adaptive resistance through a rapid rewiring of cancer cell signaling. Here we identified that WEE1 is activated after transient exposure to PI3K inhibition and confers resistance to PI3K inhibition in GBM. Methods Patient-derived glioma-initiating cells and established GBM cells were treated with PI3K inhibitor or WEE1 inhibitor alone or in combination, and cell proliferation was evaluated by CellTiter-Blue assay. Cell apoptosis was analyzed by TUNEL, annexin V staining, and blotting of cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase. Both subcutaneous xenograft and orthotropic xenograft studies were conducted to evaluate the effects of the combination on tumorigenesis; the tumor growth was monitored by bioluminescence imaging, and tumor tissue was analyzed by immunohistochemistry to validate signaling changes. Results PI3K inhibition activates WEE1 kinase, which in turn phosphorylates cell division control protein 2 homolog (Cdc2) at Tyr15 and inhibits Cdc2 activity, leading to G2/M arrest in a p53-independent manner. WEE1 inhibition abrogated the G2/M arrest and propelled cells to prematurely enter into mitosis and consequent cell death through mitotic catastrophe and apoptosis. Additionally, combination treatment significantly suppressed tumor growth in a subcutaneous model but not in an intracranial model due to limited blood-brain barrier penetration. Conclusions Our findings highlight WEE1 as an adaptive resistant gene activated after PI3K inhibition, and inhibition of WEE1 potentiated the effectiveness of PI3K targeted inhibition, suggesting that a combinational inhibition of WEE1 and PI3K might allow successful targeted therapy in GBM.

AB - Background Oncogenic activation of phosphatidylinositol-3 kinase (PI3K) signaling plays a pivotal role in the development of glioblastoma (GBM). However, pharmacological inhibition of PI3K has so far not been therapeutically successful due to adaptive resistance through a rapid rewiring of cancer cell signaling. Here we identified that WEE1 is activated after transient exposure to PI3K inhibition and confers resistance to PI3K inhibition in GBM. Methods Patient-derived glioma-initiating cells and established GBM cells were treated with PI3K inhibitor or WEE1 inhibitor alone or in combination, and cell proliferation was evaluated by CellTiter-Blue assay. Cell apoptosis was analyzed by TUNEL, annexin V staining, and blotting of cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase. Both subcutaneous xenograft and orthotropic xenograft studies were conducted to evaluate the effects of the combination on tumorigenesis; the tumor growth was monitored by bioluminescence imaging, and tumor tissue was analyzed by immunohistochemistry to validate signaling changes. Results PI3K inhibition activates WEE1 kinase, which in turn phosphorylates cell division control protein 2 homolog (Cdc2) at Tyr15 and inhibits Cdc2 activity, leading to G2/M arrest in a p53-independent manner. WEE1 inhibition abrogated the G2/M arrest and propelled cells to prematurely enter into mitosis and consequent cell death through mitotic catastrophe and apoptosis. Additionally, combination treatment significantly suppressed tumor growth in a subcutaneous model but not in an intracranial model due to limited blood-brain barrier penetration. Conclusions Our findings highlight WEE1 as an adaptive resistant gene activated after PI3K inhibition, and inhibition of WEE1 potentiated the effectiveness of PI3K targeted inhibition, suggesting that a combinational inhibition of WEE1 and PI3K might allow successful targeted therapy in GBM.

KW - mitotic catastrophic cell death

KW - PI3K inhibition resistance

KW - WEE1

UR - http://www.scopus.com/inward/record.url?scp=85040925578&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85040925578&partnerID=8YFLogxK

U2 - 10.1093/neuonc/nox128

DO - 10.1093/neuonc/nox128

M3 - Article

VL - 20

SP - 78

EP - 91

JO - Neuro-Oncology

T2 - Neuro-Oncology

JF - Neuro-Oncology

SN - 1522-8517

IS - 1

ER -