Novel resistance mechanisms to first-generation EGFR tyrosine kinase inhibitors: A perspective study in NSCLC patients using targeted next generation sequencing.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e20576-e20576
Author(s):  
Ying Jin ◽  
Jianjun Zhang ◽  
Ming Chen ◽  
Yang Shao ◽  
Xun Shi ◽  
...  
Keyword(s):  
First Generation ◽  
Kinase Inhibitors ◽  
Acquired Resistance ◽  
Resistance Mechanisms ◽  
Egfr Mutations ◽  
T790m Mutation ◽  
Targeted Next Generation Sequencing ◽  
Egfr Tyrosine Kinase Inhibitors ◽  
Nsclc Patients ◽  
Egfr T790m

e20576 Background:Patients with non-small-cell lung cancer (NSCLC) harboring sensitive epithelial growth factor receptor (EGFR) mutations invariably develop acquired resistance to EGFR tyrosine kinase inhibitors (TKIs). Identification of actionable mutations conferring drug-resistance can be helpful for guiding the subsequent treatment decision. Currently, the known mechanisms of acquired resistance includes: the secondary gatekeeper EGFR-T790M mutation, activation of members of downstream signaling pathways such as PI3K/AKT/mTOR pathway, activation of bypass signaling such as MET, and changes in tumor histology. However, the mechanisms in the remaining patients are still unknown. Methods:In this prospective study, thirty-one advanced NSCLC patients initially carrying sensitive EGFR mutations and subsequently developing acquired resistance to the first-generation EGFR-TKIs were enrolled. Pre-treatment tumor samples as well as re-biopsies of tumor and plasma when the patients were diagnosed with EGFR-TKI resistance were acquired, followed by mutation profiling using targeted next generation sequencing (NGS) on 416 cancer-related genes. Results: In total, 55% of patients were identified to carry acquired secondary EGFR-T790M mutation. Three patients (~10%) harbor EGFR-T854A mutation, which has been reported as another TKI resistant mutation. 26% and 19% of cases accumulated TP53 and RB1 mutations, respectively. In T790M/T854A-negative cases, 30% of patients acquired MET amplification. Other potential acquired resistance mechanisms includes single nucleotide variants (SNVs) in genes such as SMAD4, DNMT3A, GNAS, ATM, KRAS, PIK3CA and TET2, and copy number variations (CNVs) in genes such as CDK4, MDM2, MYC, RICTOR and ERBB2. Conclusions:The study depicted the genetic landscapes comprehensively in matched pre- and post-EGFR-TKIs samples of NSCLC population resistant to first generation TKI treatments. Our analysis demonstrates new perspectives for further study of resistance and putting forward corresponding relevant tactics against the challenge of disease progression. Clinical trial information: NCT02804217.

Prospective study for usefulness of circulating-free DNA on prediction of third generation EGFR tyrosine kinase inhibitors.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e21510-e21510
Author(s):  
Hironori Yoshida ◽  
Chiho Nakashima ◽  
Naohisa Matsumoto ◽  
Kentaro Iwanaga ◽  
Noriyuki Ebi ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Disease Progression ◽  
Tyrosine Kinase Inhibitors ◽  
Kinase Inhibitors ◽  
Egfr Mutations ◽  
Plasma Samples ◽  
Egfr Tyrosine Kinase ◽  
Egfr Tyrosine Kinase Inhibitors ◽  
Nsclc Patients ◽  
Egfr T790m

e21510 Background: Most non-small lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations develop resistance when exposed to EGFR-tyrosine kinase inhibitors (TKIs). T790M develops in about half of patients treated with TKI and can be detected by tumor tissue and cfDNA hotspot tests. However, co-occurring mutations at other loci may impact efficacy. We conducted a prospective, multi-center, observational study to assess the detection rates and predictive values of plasma-based EGFR T790M detection methods for Japanese NSCLC patients treated with osimertinib. Methods: NSCLC patients with tumor EGFR mutations and disease progression after treatment with 1st- or 2nd-generation EGFR-TKI were enrolled. Plasma was collected at the time of clinical disease progression, before osimertinib treatment. The collected plasma was tested for EGFR T90M by in-house plasma MBP-QP and ddPCR assays and compared to clinically tested cobas (Roche) results (including tissue, plasma). The primary endpoint was to demonstrate comparability of our MBP-QP system to cobas using plasma-based EGFR T790M detection to predict the therapeuitic effect of osimertinib via objective response rate (ORR) and disease control rate (DCR). As an exploratory analysis, we used Guardant360 to retrospectively test available banked plasma samples collected describe time points. Results: From Feb 2017 to Jan 2019, 145 patients enrolled. T790M was detected by cobas in 57 cases (44 tissue, 16 plasma, 3 both). ORR and DCR in plasma cobas-positive cases were 62.5% and 81.3%, respectively. MBP-QP found T790M in 9 patients with ORR and DCR 66.7% and 77.8%. ddPCR found 17 cases with ORR and DCR 70.6% and 82.4%. ORR was not correlated to AF. In plasma samples from 54 patients, Guardant360 detected T790M in 57%. Co-occurring alterations such as amplification or minor mutations in EGFR or other genes such as TP53 did not impact ORR, but in the group with poor response to osimertinib, the number of detected gene alterations tended to be large. Two patients with small cell carcinoma transformation had RB1 mutations and MYC amplification. Conclusions: Regardless of the test system, the detection of T790M could predict a good therapeutic effect of osimertinib, but there was no difference in response to osimertinib depending on EGFR T790M AF. Compared to single-gene assessment of EGFR, NGS of cfDNA may be useful for guiding treatment decisions for patients with TKI-resistant NSCLC. Clinical trial information: UMIN000025930.

Sensitivity of TargetSelector in clinical experience in ctDNA profiling of NSCLC 2000 cases.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e23033-e23033
Author(s):  
Veena M. Singh ◽  
Anthony J. Daher ◽  
Jeffery J. Chen ◽  
Lyle Arnold ◽  
Cecile Rose T. Vibat
Keyword(s):  
Kinase Inhibitors ◽  
Acquired Resistance ◽  
Growth Factor Receptor ◽  
Egfr Mutations ◽  
Wild Type ◽  
T790m Mutation ◽  
Blood Samples ◽  
Copy Numbers ◽  
Activating Mutation ◽  
Nsclc Patients

e23033 Background: Targeted cancer therapy relies on identifying specific DNA mutations from a patient’s tumor. Tyrosine kinase inhibitors (TKIs) tend to be effective for non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) activating mutations, of which exon 19 deletions (Del19) and L858R are most common. Acquired resistance to TKI therapy is associated with a T790M mutation. Standard biomarker analyses may not reflect tumor heterogeneity; they entail tissue biopsies often with surgical complications. To address these limitations, Biocept developed a minimally invasive method to characterize cancer biomarkers in blood. Biocept's proprietary TargetSelector assays selectively amplify relevant mutations from circulating tumor DNA (ctDNA). Clinical validations demonstrated high concordances between molecular tests in blood vs tissue. As further validation, EGFR mutation detection frequencies were compared to US averages (mycancergenome.org). Here we analyze 2000 blood samples received at Biocept from 1Mar 2016 to 4Jan 2017 from late stage NSCLC patients. Methods: Blood was collected in Biocept OncoCEE BCT validated to preserve DNA ≤ 8 days. TargetSelector was used to detect ctDNA L858R, Del19 and T790M.EGFR allele copy numbers for wild type and each mutant were calculated. The prevalence of each mutation was compared to US averages. Results: Del19, L858R, and T790M mutations were detected in 12.9%, 8.5%, and 9.9% of the analyzed blood samples, respectively. This is concordant with US averages, which are 10% for each mutation. Median copy numbers/ml of blood were 30 for Del19 (range: 1 – 91974), 15 for L858R (range: 1 – 91200), and 10 for T790M (range: 1 – 137360). The median wild type EGFR copy number detected/ml blood was 2304 (range: 8 – 2498725). In ~80% of T790M cases, ≥ 1 concomitant activating mutation was detected. Conclusions: Biocept's TargetSelector detects EGFR mutations (Del19, L585R, and T790M) at a very high level of sensitivity down to 1 mutant copy/ml in advanced NSCLC patients at frequencies consistent with cited US rates. Moreover, the underlying activating mutation was detected in ~80% of T790M cases.

scholarly journals The use of COLD-PCR and pyrosequencing for sensitive detection of EGFR T790M mutation

2021 ◽  
Vol 271 ◽  
pp. 03026
Author(s):  
Huimin Chen ◽  
Yang Zhang ◽  
Dan Pu ◽  
Kunxian Shu
Keyword(s):  
Kinase Inhibitors ◽  
Acquired Resistance ◽  
Growth Factor Receptor ◽  
Cost Effective ◽  
Fold Increase ◽  
Conventional Pcr ◽  
T790m Mutation ◽  
Detection Rates ◽  
Nsclc Patients ◽  
Egfr T790m

A sensitive and convenient method for the detection of epidermal growth factor receptor (EGFR) T790M mutation in non-small cell lung cancer (NSCLC) patients with acquired resistance to tyrosine kinase inhibitors (TKIs) would be desirable to guide treatment strategy. Consequently, studies have focused on sensitive characterization of EGFR T790M mutation. Herein, two methods of co-amplification at lower denaturation temperature PCR (COLD-PCR) and pyrosequencing were combined (COLDPCR/ pyrosequencing) for detecting EGFR T790M mutation. Evaluation of mutation-containing dilutions revealed that the sensitivities of COLD-PCR/pyrosequencing and conventional PCR/pyrosequencing assays for the detection of the T790M mutation were 0.1 and 5%, respectively, indicating a 50-fold increase in sensitivity. When the T790M mutation in 20 clinical NSCLC samples who had relapsed under firstgeneration EGFR TKI were further determined using COLD-PCR/pyrosequencing and conventional PCR/pyrosequencing, the detection rates were 35% (7/20) and 25% (5/20), respectively. All patients who were positive for the T790M mutation with conventional PCR/pyrosequencing were also found to be positive with COLD-PCR/pyrosequencing. The discordant cases were 2 samples with no T790M mutation detected with conventional PCR/pyrosequencing, but which were positive with COLD-PCR/pyrosequencing. COLD-PCR/pyrosequencing is a sensitive and cost-effective tool for detecting the T790M mutation which will permit an improvement of therapeutic management.

scholarly journals High expression of hypoxia inducible factor 1α related with acquired resistant to EGFR tyrosine kinase inhibitors in NSCLC

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Qian Jin ◽  
Feihua Huang ◽  
Xianrong Xu ◽  
Haidong He ◽  
Yingqing Zhang
Keyword(s):  
First Generation ◽  
Kinase Inhibitors ◽  
Acquired Resistance ◽  
Hypoxia Inducible Factor ◽  
High Expression ◽  
Normal Lung ◽  
Nsclc Tissue ◽  
T790m Mutation ◽  
Level Group ◽  
Egfr Tkis

AbstractThe acquired resistance of the first generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) is a main factor leading to poor prognosis of non-small cell lung cancer (NSCLC), so we researched whether the high expression of hypoxia-inducible factor-1α (HIF-1α) in EGFR-TKIs sensitive NSCLC tissue tends to induce the acquired resistance. We detected the HIF-1α in normal lung tissue, EGFR-TKIs sensitive NSCLC tissue, the first generation EGFR-TKIs acquired resistant NSCLC tissue and acquired EGFR T790M mutation NSCLC tissue with the method of immunohistochemistry. Then, we compared the expression of HIF-1α in these tissues, and evaluate the effect of HIF-1α expression to the occurrence of acquired resistance. The expression of HIF-1α was much higher in the EGFR-TKIs sensitive NSCLC tissue than that in normal lung tissue. HIF-1α level became higher after the occurrence acquired resistance. There was negative correlation between HIF-1α level before receiving treatment and the time of acquired resistance occurring as well as the acquired EGFR T790M mutation occurring. As the treatment going on, EGFR-TKIs sensitivity rate of low HIF-1α level group was much higher than that of high level group. The high expression of HIF-1α related with the acquired resistance of the first generation EGFR-TKIs, and HIF-1α can be a biomarker to predict the early occurrence of acquired resistance.

scholarly journals Clinical Characteristics of Osimertinib Responder in Non-Small Cell Lung Cancer Patients with EGFR-T790M Mutation

Cancers ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 365 ◽  
Author(s):  
Akihiro Yoshimura ◽  
Tadaaki Yamada ◽  
Naoko Okura ◽  
Takayuki Takeda ◽  
Kazuki Hirose ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Kinase Inhibitors ◽  
Small Cell ◽  
Small Cell Lung ◽  
T790m Mutation ◽  
Nsclc Patients ◽  
Egfr T790m ◽  
Egfr Tkis

Osimertinib is a mutant-selective EGFR inhibitor that is effective against non-small cell lung cancer (NSCLC) in patients with the EGFR-T790M mutation, who are resistant to EGFR-tyrosine kinase inhibitors (EGFR-TKIs). However, the factors affecting response to osimertinib treatment are unknown. In this retrospective study, 27 NSCLC patients with the EGFR-T790M mutation were enrolled at five institutions in Japan. Among several parameters tested, the progression-free survival (PFS) associated with the initial EGFR-TKIs was positively correlated with the PFS after osimertinib treatment (p = 0.021). The median PFS following osimertinib treatment and the overall survival (OS) were longer in patients who responded to osimertinib than in those who did not (17.7 months versus 3.5 months, p = 0.009 and 24.2 months versus 13.5 months, p = 0.021, respectively). A multivariate analysis demonstrated that the PFS with initial EGFR-TKIs was significantly related to the PFS with osimertinib treatment (p = 0.035), whereas osimertinib response was significantly related to the PFS and OS with osimertinib treatment (p = 0.016 and p = 0.006, respectively). Our retrospective observations indicate that PFS following the initial EGFR-TKI treatment and the response rate to osimertinib might be promising predictors for effective osimertinib treatment in NSCLC patients with the EGFR-T790M mutation.

Sign in / Sign up

Export Citation Format

Share Document