Dataset Information

Structural, biochemical, and clinical characterization of epidermal growth factor receptor (EGFR) exon 20 insertion mutations in lung cancer.

ABSTRACT: Epidermal growth factor receptor (EGFR) gene mutations (G719X, exon 19 deletions/insertions, L858R, and L861Q) predict favorable responses to EGFR tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC). However, EGFR exon 20 insertion mutations (~10% of all EGFR mutations) are generally associated with insensitivity to available TKIs (gefitinib, erlotinib, and afatinib). The basis of this primary resistance is poorly understood. We studied a broad subset of exon 20 insertion mutations, comparing in vitro TKI sensitivity with responses to gefitinib and erlotinib in NSCLC patients, and found that most are resistant to EGFR TKIs. The crystal structure of a representative TKI-insensitive mutant (D770_N771insNPG) reveals an unaltered adenosine triphosphate-binding pocket, and the inserted residues form a wedge at the end of the C helix that promotes the active kinase conformation. Unlike EGFR-L858R, D770_N771insNPG activates EGFR without increasing its affinity for EGFR TKIs. Unexpectedly, we find that EGFR-A763_Y764insFQEA is highly sensitive to EGFR TKIs in vitro, and patients whose NSCLCs harbor this mutation respond to erlotinib. Analysis of the A763_Y764insFQEA mutant indicates that the inserted residues shift the register of the C helix in the N-terminal direction, altering the structure in the region that is also affected by the TKI-sensitive EGFR-L858R. Our studies reveal intricate differences between EGFR mutations, their biology, and their response to EGFR TKIs.

SUBMITTER: Yasuda H

PROVIDER: S-EPMC3954775 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Structural, biochemical, and clinical characterization of epidermal growth factor receptor (EGFR) exon 20 insertion mutations in lung cancer.

Yasuda Hiroyuki H Park Eunyoung E Yun Cai-Hong CH Sng Natasha J NJ Lucena-Araujo Antonio R AR Yeo Wee-Lee WL Huberman Mark S MS Cohen David W DW Nakayama Sohei S Ishioka Kota K Yamaguchi Norihiro N Hanna Megan M Oxnard Geoffrey R GR Lathan Christopher S CS Moran Teresa T Sequist Lecia V LV Chaft Jamie E JE Riely Gregory J GJ Arcila Maria E ME Soo Ross A RA Meyerson Matthew M Eck Michael J MJ Kobayashi Susumu S SS Costa Daniel B DB

Science translational medicine 20131201 216

Epidermal growth factor receptor (EGFR) gene mutations (G719X, exon 19 deletions/insertions, L858R, and L861Q) predict favorable responses to EGFR tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC). However, EGFR exon 20 insertion mutations (~10% of all EGFR mutations) are generally associated with insensitivity to available TKIs (gefitinib, erlotinib, and afatinib). The basis of this primary resistance is poorly understood. We studied a broad subset of exon 20 inse ...[more]

PMID: 24353160

Similar Datasets

Project description:BackgroundEpidermal growth factor receptor exon 20 insertion (EGFRex20ins) mutations represent approximately 4-12% of EGFR mutations and are generally refractory to the 1st and 2nd generation EGFR tyrosine kinase inhibitors (TKIs). Development of effective therapies for patients with EGFRex20ins mutant non-small-cell lung carcinoma (NSCLC) represents a great unmet need. Preclinical models have shown that osimertinib is active in NSCLC harboring EGFRex20ins, while the antitumor activity of osimertinib remains to be evaluated in patients with EGFRex20ins mutations.MethodsTumor genotyping was performed in 2316 Chinese NSCLC cases with targeted next generation sequencing (NGS) covering the whole exons of EGFR gene. The frequency and genetic characteristics of EGFRexon20ins mutations were analyzed. Furthermore, six patients with specific EGFRexon20ins mutations and receiving osimertinib 80?mg once daily were retrospectively included to assess the antitumor activity and safety of monotherapy osimertinib.ResultsEGFRex20ins mutations were identified in 4.8% (53/1095) of EGFR mutant NSCLC and 2.3% (53/2316) of all NSCLC cases. The most frequently identified EGFRexon20ins is A767_V769dup (17/53,32.1%). We found that the genetic characteristics of EGFRex20ins mutations in Chinese patients with NSCLC were comparable to those reported in Caucasian patients. Four patients with osimertinib therapy achieved partial response and the rest stable disease. Median progression free survival (PFS) was 6.2?months (95% confidence interval 5.0-12.9?months; range 4.9-14.6?months). The most common adverse events (AEs) were diarrhea (2/6), pruritis (2/6), stomatitis (1/6) and nausea (1/6). No grade 3 or more AEs were documented.ConclusionsThis study revealed that the genetic characteristics of EGFRex20ins mutations in Chinese patients with NSCLC were comparable to those reported in Caucasian patients. Furthermore, our study firstly demonstrated promising antitumor activity of osimertinib in certain EGFRex20ins mutant advanced NSCLC patients, indicating that osimertinib treatment for EGFRex20ins positive patients deserves further study.

Project description:BackgroundEpidermal growth factor receptor exon 20 insertions (EGFR ex20ins) occur in about 4-14% of lung adenocarcinoma (LUAD) patients with EGFR mutations. Recently some targeted drugs have been approved for the treatment of LUAD patients with EGFR ex20ins. However, the heterogeneity of EGFR ex20ins mutations and resultant challenges in identifying them have led to the underestimation of their frequency.MethodsWe investigated the molecular and clinicopathologic features of EGFR ex20ins in 3,892 Chinese LUAD patients using next-generation sequencing (NGS). The frequency and distribution of EGFR ex20ins mutations between Chinese and Western LUAD patients were also compared by integrating the data of this study and the data of previous studies.ResultsA total of 23 unique EGFR ex20ins were identified in 77 LUAD patients, accounting for 1.98% of all LUAD patients and 3.49% of EGFR mutant LUDA patients. The 2 most common EGFR ex20ins subtypes were S768_D770dup and A767_V769dup, which together accounted for 55.84% of the EGFR ex20ins cases. About 61% (14/23) of the EGFR ex20ins subtypes occurred only once. Additionally, 8 of the EGFR ex20ins subtypes were not recorded in the COSMIC database. These results showed that the EGFR ex20ins mutations were highly heterogeneous. There was no significant difference in the frequency and distribution of EGFR ex20ins mutations between Chinese and Western LUAD patients, but the frequency of EGFR ex20ins mutations was significantly lower in EGFR-mutant Chinese LUAD patients than Western LUAD patients. The co-mutation analysis showed that EGFR ex20ins occurred significantly and exclusively with certain driver genes in LUAD, including ALK fusion (χ2=7.133, P=0.008), KRAS (χ2=8.468, P=0.004), and PIK3CA (χ2=5.792, P=0.016). No gene was observed to be significantly co-mutated with EGFR ex20ins. In general, patients with EGFR ex20ins shared a similar age and gender to patients with other EGFR mutations or without EGFR ex20ins.ConclusionsOverall, our results revealed the molecular and clinicopathologic features of EGFR ex20ins in Chinese LUAD patients, which will be helpful for drug development and in clinical trials targeting EGFR ex20ins.

Dataset Information

Structural, biochemical, and clinical characterization of epidermal growth factor receptor (EGFR) exon 20 insertion mutations in lung cancer.

Publications

Structural, biochemical, and clinical characterization of epidermal growth factor receptor (EGFR) exon 20 insertion mutations in lung cancer.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets