Abstract

Introduction: Osimertinib is an effective third-generation tyrosine kinase inhibitor (TKI) for EGFR-mutant lung cancers. However, treatment for patients with acquired resistance to osimertinib remains challenging. We characterized a novel EGFR mutation in exon 20 that was acquired while on osimertinib. Methods: A 79-year-old woman had disease progression during third-line treatment with osimertinib for an EGFR L858R/T790M–mutant lung cancer. Sequencing of circulating cell-free DNA showed EGFR L858R, an acquired novel EGFR M766Q mutation in exon 20, and no evidence of EGFR T790M. Homology modeling was performed to investigate the effects of M766Q on binding to osimertinib. L858R and L858R/M766Q mutations were retrovirally introduced into Ba/F3 and NIH/3T3 cells and evaluated for sensitivity to first-generation (erlotinib), second-generation (afatinib, neratinib, and poziotinib), and third-generation TKIs (osimertinib) by cell viability and colony-formation assays. EGFR-mediated signaling pathways were interrogated by western blotting. Results: Modeling suggested that EGFR M766Q could disrupt osimertinib binding. L858R/M766Q double-mutant cells were 12-fold more resistant to osimertinib, and more than 250-fold more resistant to erlotinib and afatinib, as compared to L858R-mutant cells. In contrast, double-mutant cells remained sensitive to neratinib and poziotinib at clinically relevant doses (concentration that inhibits 50%, 4.3 and 1.3 nM, respectively). This was corroborated by the effects of the TKIs on colony formation and EGFR signaling. Conclusions: Acquisition of EGFR M766Q exon 20 mutation is a novel mechanism of acquired resistance to osimertinib. EGFR-mutant lung cancers with an acquired EGFR M766Q mutation in the setting of osimertinib resistance may be sensitive to neratinib and poziotinib.

Original languageEnglish (US)
Pages (from-to)1982-1988
Number of pages7
JournalJournal of Thoracic Oncology
Volume14
Issue number11
DOIs
StatePublished - Nov 2019

Fingerprint

Exons
Mutation
Lung Neoplasms
N-(4-(3-chloro-4-(2-pyridinylmethoxy)anilino)-3-cyano-7-ethoxy-6-quinolyl)-4-(dimethylamino)-2-butenamide
HM781-36B
Adenocarcinoma of lung
osimertinib
NIH 3T3 Cells
Protein-Tyrosine Kinases
Disease Progression
Cell Survival
Western Blotting
DNA
Therapeutics

All Science Journal Classification (ASJC) codes

  • Oncology
  • Pulmonary and Respiratory Medicine

Keywords

  • EGFR
  • Lung adenocarcinoma
  • Neratinib
  • Osimertinib resistance
  • Poziotinib

Cite this

@article{b63c13811a1e42ef9290b7616cbb8bfd,
title = "A Novel Acquired Exon 20 EGFR M766Q Mutation in Lung Adenocarcinoma Mediates Osimertinib Resistance but is Sensitive to Neratinib and Poziotinib",
abstract = "Introduction: Osimertinib is an effective third-generation tyrosine kinase inhibitor (TKI) for EGFR-mutant lung cancers. However, treatment for patients with acquired resistance to osimertinib remains challenging. We characterized a novel EGFR mutation in exon 20 that was acquired while on osimertinib. Methods: A 79-year-old woman had disease progression during third-line treatment with osimertinib for an EGFR L858R/T790M–mutant lung cancer. Sequencing of circulating cell-free DNA showed EGFR L858R, an acquired novel EGFR M766Q mutation in exon 20, and no evidence of EGFR T790M. Homology modeling was performed to investigate the effects of M766Q on binding to osimertinib. L858R and L858R/M766Q mutations were retrovirally introduced into Ba/F3 and NIH/3T3 cells and evaluated for sensitivity to first-generation (erlotinib), second-generation (afatinib, neratinib, and poziotinib), and third-generation TKIs (osimertinib) by cell viability and colony-formation assays. EGFR-mediated signaling pathways were interrogated by western blotting. Results: Modeling suggested that EGFR M766Q could disrupt osimertinib binding. L858R/M766Q double-mutant cells were 12-fold more resistant to osimertinib, and more than 250-fold more resistant to erlotinib and afatinib, as compared to L858R-mutant cells. In contrast, double-mutant cells remained sensitive to neratinib and poziotinib at clinically relevant doses (concentration that inhibits 50{\%}, 4.3 and 1.3 nM, respectively). This was corroborated by the effects of the TKIs on colony formation and EGFR signaling. Conclusions: Acquisition of EGFR M766Q exon 20 mutation is a novel mechanism of acquired resistance to osimertinib. EGFR-mutant lung cancers with an acquired EGFR M766Q mutation in the setting of osimertinib resistance may be sensitive to neratinib and poziotinib.",
keywords = "EGFR, Lung adenocarcinoma, Neratinib, Osimertinib resistance, Poziotinib",
author = "Castellano, {Gina M.} and Joseph Aisner and Burley, {Stephen K.} and Brinda Vallat and Yu, {Helena A.} and Pine, {Sharon R.} and Shridar Ganesan",
year = "2019",
month = "11",
doi = "10.1016/j.jtho.2019.06.015",
language = "English (US)",
volume = "14",
pages = "1982--1988",
journal = "Journal of Thoracic Oncology",
issn = "1556-0864",
publisher = "International Association for the Study of Lung Cancer",
number = "11",

}

TY - JOUR

T1 - A Novel Acquired Exon 20 EGFR M766Q Mutation in Lung Adenocarcinoma Mediates Osimertinib Resistance but is Sensitive to Neratinib and Poziotinib

AU - Castellano, Gina M.

AU - Aisner, Joseph

AU - Burley, Stephen K.

AU - Vallat, Brinda

AU - Yu, Helena A.

AU - Pine, Sharon R.

AU - Ganesan, Shridar

PY - 2019/11

Y1 - 2019/11

N2 - Introduction: Osimertinib is an effective third-generation tyrosine kinase inhibitor (TKI) for EGFR-mutant lung cancers. However, treatment for patients with acquired resistance to osimertinib remains challenging. We characterized a novel EGFR mutation in exon 20 that was acquired while on osimertinib. Methods: A 79-year-old woman had disease progression during third-line treatment with osimertinib for an EGFR L858R/T790M–mutant lung cancer. Sequencing of circulating cell-free DNA showed EGFR L858R, an acquired novel EGFR M766Q mutation in exon 20, and no evidence of EGFR T790M. Homology modeling was performed to investigate the effects of M766Q on binding to osimertinib. L858R and L858R/M766Q mutations were retrovirally introduced into Ba/F3 and NIH/3T3 cells and evaluated for sensitivity to first-generation (erlotinib), second-generation (afatinib, neratinib, and poziotinib), and third-generation TKIs (osimertinib) by cell viability and colony-formation assays. EGFR-mediated signaling pathways were interrogated by western blotting. Results: Modeling suggested that EGFR M766Q could disrupt osimertinib binding. L858R/M766Q double-mutant cells were 12-fold more resistant to osimertinib, and more than 250-fold more resistant to erlotinib and afatinib, as compared to L858R-mutant cells. In contrast, double-mutant cells remained sensitive to neratinib and poziotinib at clinically relevant doses (concentration that inhibits 50%, 4.3 and 1.3 nM, respectively). This was corroborated by the effects of the TKIs on colony formation and EGFR signaling. Conclusions: Acquisition of EGFR M766Q exon 20 mutation is a novel mechanism of acquired resistance to osimertinib. EGFR-mutant lung cancers with an acquired EGFR M766Q mutation in the setting of osimertinib resistance may be sensitive to neratinib and poziotinib.

AB - Introduction: Osimertinib is an effective third-generation tyrosine kinase inhibitor (TKI) for EGFR-mutant lung cancers. However, treatment for patients with acquired resistance to osimertinib remains challenging. We characterized a novel EGFR mutation in exon 20 that was acquired while on osimertinib. Methods: A 79-year-old woman had disease progression during third-line treatment with osimertinib for an EGFR L858R/T790M–mutant lung cancer. Sequencing of circulating cell-free DNA showed EGFR L858R, an acquired novel EGFR M766Q mutation in exon 20, and no evidence of EGFR T790M. Homology modeling was performed to investigate the effects of M766Q on binding to osimertinib. L858R and L858R/M766Q mutations were retrovirally introduced into Ba/F3 and NIH/3T3 cells and evaluated for sensitivity to first-generation (erlotinib), second-generation (afatinib, neratinib, and poziotinib), and third-generation TKIs (osimertinib) by cell viability and colony-formation assays. EGFR-mediated signaling pathways were interrogated by western blotting. Results: Modeling suggested that EGFR M766Q could disrupt osimertinib binding. L858R/M766Q double-mutant cells were 12-fold more resistant to osimertinib, and more than 250-fold more resistant to erlotinib and afatinib, as compared to L858R-mutant cells. In contrast, double-mutant cells remained sensitive to neratinib and poziotinib at clinically relevant doses (concentration that inhibits 50%, 4.3 and 1.3 nM, respectively). This was corroborated by the effects of the TKIs on colony formation and EGFR signaling. Conclusions: Acquisition of EGFR M766Q exon 20 mutation is a novel mechanism of acquired resistance to osimertinib. EGFR-mutant lung cancers with an acquired EGFR M766Q mutation in the setting of osimertinib resistance may be sensitive to neratinib and poziotinib.

KW - EGFR

KW - Lung adenocarcinoma

KW - Neratinib

KW - Osimertinib resistance

KW - Poziotinib

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U2 - 10.1016/j.jtho.2019.06.015

DO - 10.1016/j.jtho.2019.06.015

M3 - Article

C2 - 31254668

AN - SCOPUS:85072018727

VL - 14

SP - 1982

EP - 1988

JO - Journal of Thoracic Oncology

JF - Journal of Thoracic Oncology

SN - 1556-0864

IS - 11

ER -