Loss of p120ctn causes EGFR-targeted therapy resistance and failure

PLoS One. 2020 Oct 28;15(10):e0241299. doi: 10.1371/journal.pone.0241299. eCollection 2020.

Abstract

Epidermal growth factor receptor (EGFR) plays a vital role in cell division and survival signaling pathways. EGFR is activated in nearly every cancer type, and its high expression in tumors is correlated with poor patient outcome. Altogether, EGFR is a prime candidate as a therapeutic target. While targeted EGFR therapy is initially effective in 75% of patients, a majority of patients relapse within the first year due to poorly understood mechanisms of resistance. p120-catenin (p120ctn) has recently been implicated as a biomarker for EGFR therapy. In previous studies, we demonstrated that p120ctn is a tumor suppressor and its loss is capable of inducing cancer. Furthermore, p120ctn down-regulation synergizes with EGFR overexpression to cause a highly invasive cell phenotype. The purpose of this present study was to investigate whether p120ctn down-regulation induced EGFR therapeutic resistance. Using human esophageal keratinocytes, we have found that EGFR-targeting compounds are toxic to cells overexpressing EGFR. Interestingly, these therapies do not cause toxicity in cells with EGFR overexpression and decreased p120ctn expression. These data suggest that decreased p120ctn causes resistance to EGFR therapy. We believe these findings are of utmost importance, as there is an unmet need to discover mechanisms of EGFR resistance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Monoclonal / pharmacology
  • Antibodies, Monoclonal / therapeutic use
  • Apoptosis / drug effects
  • Catenins / deficiency*
  • Catenins / metabolism
  • Cell Line, Tumor
  • Cetuximab / pharmacology
  • Delta Catenin
  • Down-Regulation / drug effects
  • Drug Resistance, Neoplasm*
  • ErbB Receptors / antagonists & inhibitors
  • ErbB Receptors / metabolism*
  • Erlotinib Hydrochloride / pharmacology
  • Esophagus / pathology
  • Gefitinib / pharmacology
  • Humans
  • Keratinocytes / drug effects
  • Keratinocytes / metabolism
  • Molecular Targeted Therapy*
  • NF-kappa B / metabolism
  • Protein Kinase Inhibitors / pharmacology
  • Treatment Outcome

Substances

  • Antibodies, Monoclonal
  • Catenins
  • NF-kappa B
  • Protein Kinase Inhibitors
  • Erlotinib Hydrochloride
  • ErbB Receptors
  • Cetuximab
  • Gefitinib
  • Delta Catenin
  • CTNND1 protein, human

Grants and funding

This research was supported by a Research Scholar Grant, RSG-16-219-01–TBG, from the American Cancer Society, a Department of Pathology Researcher-Initiated Grant, as well as an ET Program Development Award and a Program Project Development Award, both from the Penn State Cancer Institute and Highmark Community Health Reinvestment Grant (all to DBS). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.