EGFR Suppresses p53 Function by Promoting p53 Binding to DNA-PKcs: A Noncanonical Regulatory Axis Between EGFR and Wild-Type p53 in Glioblastoma

Authors

Jie Ding
Xiaolong Li
Sabbir Khan
Chen Zhang
Feng Gao
Shayak Sen
Amanda R Wasylishen
Yang Zhao
Guillermina Lozano
Dimpy Koul
W K Alfred Yung

Publication Date

10-3-2022

Journal

Neuro-Oncology

DOI

10.1093/neuonc/noac105

PMID

35474131

PMCID

PMC9527520

PubMedCentral® Posted Date

4-26-2022

PubMedCentral® Full Text Version

Post-print

Abstract

Background: Epidermal growth factor receptor (EGFR) amplification and TP53 mutation are the two most common genetic alterations in glioblastoma multiforme (GBM). A comprehensive analysis of the TCGA GBM database revealed a subgroup with near mutual exclusivity of EGFR amplification and TP53 mutations indicative of a role of EGFR in regulating wild-type-p53 (wt-p53) function. The relationship between EGFR amplification and wt-p53 function remains undefined and this study describes the biological significance of this interaction in GBM.

Methods: Mass spectrometry was used to identify EGFR-dependent p53-interacting proteins. The p53 and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) interaction was detected by co-immunoprecipitation. We used CRISPR-Cas9 gene editing to knockout EGFR and DNA-PKcs and the Edit-R CRIPSR-Cas9 system for conditional knockout of EGFR. ROS activity was measured with a CM-H2DCFDA probe, and real-time PCR was used to quantify expression of p53 target genes.

Results: Using glioma sphere-forming cells (GSCs), we identified, DNA-PKcs as a p53 interacting protein that functionally inhibits p53 activity. We demonstrate that EGFR knockdown increased wt-p53 transcriptional activity, which was associated with decreased binding between p53 and DNA-PKcs. We further show that inhibition of DNA-PKcs either by siRNA or an inhibitor (nedisertib) increased wt-p53 transcriptional activity, which was not enhanced further by EGFR knockdown, indicating that EGFR suppressed wt-p53 activity through DNA-PKcs binding with p53. Finally, using conditional EGFR-knockout GSCs, we show that depleting EGFR increased animal survival in mice transplanted with wt-p53 GSCs.

Conclusion: This study demonstrates that EGFR signaling inhibits wt-p53 function in GBM by promoting an interaction between p53 and DNA-PKcs.

Keywords

Animals, DNA, DNA-Activated Protein Kinase, ErbB Receptors, Glioblastoma, Glioma, Mice, Pyridazines, Quinazolines, RNA, Small Interfering, Reactive Oxygen Species, Tumor Suppressor Protein p53, DNA-PKcs, EGFR, glioblastoma, wt-p53

Published Open-Access

yes

Recommended Citation

Ding, Jie; Li, Xiaolong; Khan, Sabbir; et al., "EGFR Suppresses p53 Function by Promoting p53 Binding to DNA-PKcs: A Noncanonical Regulatory Axis Between EGFR and Wild-Type p53 in Glioblastoma" (2022). Faculty, Staff and Student Publications. 4788.
https://digitalcommons.library.tmc.edu/uthgsbs_docs/4788