Differential activity of afatinib (AFAT), cetuximab (CET), and erlotinib (E) in a patient-derived xenograft (PDX) model of acquired E resistance.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 8110-8110 ◽  
Author(s):  
Philip C. Mack ◽  
Neal Goodwin ◽  
William S. Holland ◽  
Karen Kelly ◽  
Primo Lara ◽  
...  

8110 Background: The UC Davis - Jackson Labs Consortium has established a PDX resource of over 50 NSCLC models (12 EGFR mutant) for experimental therapeutics and personalized medicine, using the NSG mouse. Here we report on a unique PDX model, LG703, derived from a patient at time of acquired E resistance. This tumor harbors EGFR L858R with no T790M mutation, high MET and very high EGFR protein expression. The patient is in remission following treatment with AFAT-CET. In this model, we investigated the respective contribution of CET and AFAT relative to E on tumor growth and signal transduction. Methods: Individual mice implanted with LG703 tumor fragments were randomized to E (50 mg/kg qd po), AFAT (20 mg/kg qd po), CET (10 mg/kg twice weekly iv), AFAT-CET, or vehicle control (n per arm = 12) for 3 weeks followed by a 75-day monitoring period. Changes in signal transduction mediators and RTKs were assessed after 6 and 24h treatment exposures using kinase arrays (R&D systems) and immunoblotting. Results: AFAT, CET and AFAT-CET resulted in complete tumor response (CR) during the 21-day treatment period; whereas E resulted in temporary growth delay. After cessation of treatment, E-treated mice progressed rapidly and AFAT-treated mice progressed within 2 weeks. Mice treated with CET or AFAT-CET remained in complete remission. At 6h, E and AFAT significantly (>70%) reduced EGFR phosphorylation as well as that of AKT1, AKT2, ERK1, p38a, RSK1 and p70S6K. At 24h, E-treated tumors had returned to baseline-like states for all factors, AFAT showed an intermediate response, and CET, alone or with AFAT, achieved the greatest inhibition of pEGFR with sustained inhibition of all downstream effectors. Conclusions: In the LG703 PDX model, CET and AFAT+CET resulted in CRs, mirroring the patient's response to similar therapy, associated with sustained inhibition of pEGFR and multiple downstream signaling factors. In contrast, E exhibited only temporary growth delay associated with transient inhibition of EGFR pathway factors. These experiments demonstrate the potential of this PDX resource to assess new therapeutic strategies in models representing individual patients. Supported by BJALCF.

2018 ◽  
Vol 19 (2) ◽  
pp. e247-e252 ◽  
Author(s):  
Takahisa Kawamura ◽  
Hirotsugu Kenmotsu ◽  
Shota Omori ◽  
Kazuhisa Nakashima ◽  
Kazushige Wakuda ◽  
...  

2019 ◽  
Vol 12 (2) ◽  
pp. 625-630 ◽  
Author(s):  
Mike Ralki ◽  
Brigitte Maes ◽  
Karin Pat ◽  
Jokke Wynants ◽  
Kristof Cuppens

Epidermal growth factor receptor (EGFR)-targeted therapy has become standard of care in advanced stages EGFR-mutant non-small cell lung cancer. Acquired resistance to first-line EGFR-tyrosine kinase inhibitor (TKI) and subsequent disease progression is a common problem and mostly due to a secondary mutation (T790M) in EGFR. We report a case of a patient with EGFR-mutated lung adenocarcinoma who developed a complex resistance profile: T790M mutation, HER2 mutation and HER2 amplification after first-line EGFR-TKI. This patient was safely treated with a combination of osimertinib and trastuzumab and achieved a clinically meaningful and clear molecular response.This is the first reported case of acquired resistance to first-line EGFR-TKI based on three resistance mechanisms, treated with molecular targeted combination therapy.


2010 ◽  
Vol 391 (9) ◽  
Author(s):  
John T. Heiker ◽  
David Kosel ◽  
Annette G. Beck-Sickinger

Abstract The adipocytokine adiponectin and its receptor (AdipoR) comprise a new receptor-ligand system that is involved in a variety of clinically important morbidities such as obesity, type 2 diabetes and cardiovascular diseases. Adiponectin exerts a multitude of beneficial and tissue specific effects depending on its unique, tightly regulated multimerization behavior. Post-translational modifications are essential for the multimer assembly before secretion and protein stability in the circulation. AdipoR1 and 2 have been discovered as a new class of heptahelix receptors structurally and functionally distinct from G-protein-coupled receptors. Both AdipoRs bind adiponectin and the downstream signaling of both AdipoRs is mediated mainly by phosphorylation of AMPK and activation of peroxisome proliferator-activated receptor α, which influence the lipid and glucose metabolism of skeletal muscle and liver cells as well as inflammatory processes and vascular endothelial integrity. Several intracellular binding partners of the AdipoR N-terminus such as APPL1, CK2β and ERp46 have been identified and shown to control receptor signaling. Adiponectin has also been reported to modulate the dimerization and internalization of AdipoRs, which provides new insights into the molecular characteristics of this unusual receptor. The understanding of the functional mechanisms of adiponectin signal transduction is critical to benefit from the full therapeutic potential of the adiponectin-AdipoR system.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 9031-9031
Author(s):  
Daria Gaut ◽  
Myung Shin Sim ◽  
Brian R. Wolf ◽  
Phillip A. Abarca ◽  
James M. Carroll ◽  
...  

9031 Background: The secondary T790M mutation accounts for more than 50% of acquired tyrosine kinase inhibitor (TKI) resistance in epidermal growth factor receptor (EGFR)-mutant NSCLC patients. Recent reports suggest this resistance mutation may be more common among patients with longer progression-free survival (PFS) on first-line TKI therapy, but much is still unknown about this resistance mechanism’s association with response to other therapies. Methods: Our group collected medical records from patients who underwent a biopsy for T790M mutation testing in the process of screening for clinical trials involving third generation EGFR inhibitors. Medical records were retrospectively analyzed for demographic data, PFS, best response (BR) to previous therapies, and presence or absence of an acquired T790M mutation. Progression-free survival was estimated using the Kaplan-Meier method and compared across two groups using the log-ranked test followed by univariate and multivariate cox proportional hazard regression analysis. Response rates were compared using Fisher’s exact test. Results: Out of 102 patients who obtained a diagnostic biopsy, 73 patients had a T790M mutation. Patients who later developed a T790M mutation had a longer PFS on first-line TKI therapy (12.0 months in T790M+ vs. 8.0 months in T790M-, p = 0.038, HR 1.66, 95% CI 1.03-2.67), though there was no difference in response rate (75.5% in T790M+ vs 77.3% in T790M-, p = 1.00). T790M+ patients also had a longer PFS on initial chemotherapy treatment (5.0 months in T790M+ vs. 4.0 months in T790M-, p = 0.020, HR 1.97, 95% CI 1.11-3.49) and a higher response rate to chemotherapy (22.7% in T790M+ vs 0% in T790M-, p = 0.033). Median PFS was short (3.0 months) for patients treated with immunotherapy with no difference based on T790M mutation status (p = 0.33). Conclusions: Our study confirms that tumors expressing T790M have a more indolent progression of disease compared to their T790M negative counterparts when treated with both first-line TKI and cytotoxic chemotherapy. This data provides context for therapeutic decision making in EGFR-mutant NSCLC patients.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e20545-e20545 ◽  
Author(s):  
Chul Kim ◽  
Nitin Roper ◽  
Chuong D. Hoang ◽  
Eva Szabo ◽  
Maureen Connolly ◽  
...  

e20545 Background: EGFR tyrosine kinase inhibitors (EGFR-TKIs) improve progression-free survival (PFS) in patients with EGFR-mutant NSCLC, but disease progression limits efficacy. Retrospective studies show a survival benefit to LAT in patients with oligoprogressive disease (progression at a limited number of anatomic sites). Methods: This is a prospective study of LAT in patients with oligoprogressive EGFR-mutant NSCLC. Patients with no prior EGFR-TKI therapy (cohort 1) or progression after 1st/2ndgeneration EGFR-TKIs with acquired T790M mutation (cohort 2) receive osimertinib. Upon progression, eligible patients with < = 5 progressing sites undergo LAT and resume osimertinib until disease progression. Patients previously treated with osimertinib qualifying for LAT upon disease progression are also eligible for treatment (cohort 3). Primary endpoint: evaluation of safety and efficacy of reinitiation of osimertinib after LAT (assessed by PFS). Additional goals are assessment of mechanisms of resistance to osimertinib by multi-omics analyses of tumor, blood, and saliva. Results: Between 04/2016 and 01/2017, 15 patients were enrolled (cohort 1: 9, cohort 2: 3, cohort 3: 3). Median age was 57 (range 36-71). Treatment was well tolerated. The most common adverse events (AEs) were rash, diarrhea, thrombocytopenia, and alanine transaminase elevation. Grade 3/4 AEs were observed in 4 (27%) patients. Among evaluable patients, objective response rates prior to LAT in cohorts 1 and 2 were 71% (5/7) and 100% (2/2), respectively, with 6.8 months median PFS (95% CI: 3.4 months-undefined) in cohort 1 and no progressions in cohort 2. To date, 5 patients (33%; cohort 1: 2; cohort 3: 3) had LAT. Two patients with 3 progressing sites underwent a combination of surgery and radiation. Three patients with 1 progressing site underwent surgery alone. Post-LAT PFS and results of molecular analyses will be presented. Conclusions: Patients with EGFR-mutant NSCLC and oligoprogression after EGFR-TKI therapy can be safely treated with LAT. In selected patients, this approach could potentially maximize duration of EGFR-TKI treatment and prevent premature switching to other systemic therapies. Clinical trial information: NCT02759835.


2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e20603-e20603
Author(s):  
Ying Jin ◽  
Hua Bao ◽  
Xiuning Le ◽  
Xiaojun Fan ◽  
Ming Tang ◽  
...  

e20603 Background: EGFR-mutant non-small-cell lung cancer (NSCLC) patients inevitably develop drug resistance when treated with EGFR tyrosine kinase inhibitors (TKIs). Clonal and clinical analyses of genetic alterations at baseline and progressive disease (PD), as well as differences between acquired T790M and T790M-negative patients in drug-resistant mechanisms, have not been systematically studied. Methods: We performed targeted sequencing of pre-treatment and PD tumor samples from 54 EGFR-mutant NSCLC patients. Correlation between genomic features and patients’ progression-free survival (PFS) was evaluated. Ten additional patients were sequenced using whole exome sequencing to infer the clonal evolution patterns. Results: We observed new pathways limiting EGFR-inhibitor response, including NOTCH1/ STK11 co-deletion, and TGF-beta alterations. Besides acquired T790M mutation, chromosomal instability (CIN) related genes including AURKA and TP53 alterations were the most frequently acquired events. CIN significantly increased with TKI treatment in T790M-negative patients. Transcriptional regulators including HNF1A, ATRX and NKX2-1 acquired alterations were enriched in T790M-positive patients, and diverse oncogenic pathway alterations were more common in T790M-negative patients. T790M-positive patients had improved PFS compared to T790M-negative patients. We identified subgroups within T790M-positive or T790M-negative patients with distinct PFS. Interestingly, we observed a death-and-birth process of RTK-RAS mutations during TKI treatment, and baseline and acquired RTK-RAS mutations had opposite effects on PFS. Clonal evolution analysis indicated progression of T790M-positive patients depends on competition between T790M and non-T790M resistant subclones. Conclusions: T790M-positive and T790M-negative patients display divergent landscape of acquired somatic events. Subgroups of patients were identified within T790M-positive and T790M-negative patients with distinct survival. Our results point the importance of clonal competition between T790M and non-T790M resistant subclones.


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