scholarly journals Anti-EGFR antibody 528 binds to domain III of EGFR at a site shifted from the cetuximab epitope

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Koki Makabe ◽  
Takeshi Yokoyama ◽  
Shiro Uehara ◽  
Tomomi Uchikubo-Kamo ◽  
Mikako Shirouzu ◽  
...  

AbstractAntibodies have been widely used for cancer therapy owing to their ability to distinguish cancer cells by recognizing cancer-specific antigens. Epidermal growth factor receptor (EGFR) is a promising target for the cancer therapeutics, against which several antibody clones have been developed and brought into therapeutic use. Another antibody clone, 528, is an antagonistic anti-EGFR antibody, which has been the focus of our antibody engineering studies to develop cancer drugs. In this study, we explored the interaction of 528 with the extracellular region of EGFR (sEGFR) via binding analyses and structural studies. Dot blotting experiments with heat treated sEGFR and surface plasmon resonance binding experiments revealed that 528 recognizes the tertiary structure of sEGFR and exhibits competitive binding to sEGFR with EGF and cetuximab. Single particle analysis of the sEGFR–528 Fab complex via electron microscopy clearly showed the binding of 528 to domain III of sEGFR, the domain to which EGF and cetuximab bind, explaining its antagonistic activity. Comparison between the two-dimensional class average and the cetuximab/sEGFR crystal structure revealed that 528 binds to a site that is shifted from, rather than identical to, the cetuximab epitope, and may exclude known drug-resistant EGFR mutations.

Author(s):  
Leiming Xia ◽  
Lu Wen ◽  
Siying Wang

: EGFR-TKIs are facing a big challenge of everlasting activated EGFR mutations which lack of effective binding sites, this barrier confers the dark sides that largely limited the outcome of NSCLC patients in clinic. Combination strategies show impressive anti-tumor efficacy comparing with EGFR-TKI mono-treatment, especially targeting both stem cells and non-stem cells. SHP2 (Src homology 2-containing phosphotyrosine phosphatase 2) plays an important role in regulating various malignant biology through hyper-activating intracellular pathways due to either over expression or catalytical mutation. Some pathways that SHP2 involved in were overlaps with EGFR downstream, and others were not subject to EGFR. Interestingly, SHP2 suppression was reported that can destroy the stemness of cancer. Therefore, we hypothesize SHP2 inhibitor might be an promising drug that could synergistically enhance or sensitize the anti-tumor efficacy of EGFR-TKIs in EGFR mutated NSCLC patients. Here, we summarized the mechanisms of SHP2 in regulating EGFR mutated NSCLC patients, attempted to reveal the potential synergistic effects of SHP2 inhibitor combined with EGFR-TKIs.


2021 ◽  
pp. 030089162110055
Author(s):  
Dashi Zhao ◽  
Jun Fan ◽  
Li Peng ◽  
Bo Huang ◽  
Yili Zhu ◽  
...  

Epidermal growth factor receptor ( EGFR) mutations and anaplastic lymphoma kinase ( ALK) rearrangements are considered mutually exclusive in non-small cell lung cancer (NSCLC), especially in lung adenocarcinoma (LUAC). However, sporadic cases harboring concomitant EGFR and ALK alterations have been increasingly reported. There is no consensus opinion regarding the treatment of patients positive for both molecular alterations. NSCLC with EGFR/ ALK coalterations should be separated into two subtypes: unifocal and multifocal LUAC. Here, we present an overview of the available literature regarding this rare group of patients to provide useful suggestions for therapeutic strategies.


2021 ◽  
pp. 107815522110191
Author(s):  
Pinar Gursoy

Introduction Most patients with non-small-cell lung cancer tumors that have epidermal growth factor receptor (EGFR) mutations have deletion mutations in exon 19 or exon 21, or both.In recent years, targeted therapies in lung cancer have increased survival, but the development of resistance to these drugs poses a major problem. Thesubstitution of methionineforthreonine at position 790 (T790M) mutation,is primarily responsible for this resistance. However, after osimertinib used in T790M positivepatients treatment options are generally limited to chemotherapy. Case report We reported the efficacy of erlotinib, which we reapplied due to the disappearance of the resistance mutation after osimertinib in a 68-year-old patient using osimertinib after erlotinib. Management and outcome: In the patient using erlotinib due to exon 19 deletion when progression was observed and T790M positivity was detected, osimertinib treatment was initiated. However, when T790M was found to be negative with rebiopsy in progression after osimertinib, a complete response was achieved by restarting erlotinib. Discussion The strategy of restarting erlotinib treatment with negative T790M mutation detected in biopsies of patients with osimertinib resistance may be an acceptable treatment option.


2009 ◽  
Vol 27 (9) ◽  
pp. 1394-1400 ◽  
Author(s):  
Akira Inoue ◽  
Kunihiko Kobayashi ◽  
Kazuhiro Usui ◽  
Makoto Maemondo ◽  
Shoji Okinaga ◽  
...  

Purpose This multicenter phase II study was undertaken to investigate the efficacy and feasibility of gefitinib for patients with advanced non–small-cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations without indication for chemotherapy as a result of poor performance status (PS). Patients and Methods Chemotherapy-naïve patients with poor PS (patients 20 to 74 years of age with Eastern Cooperative Oncology Group PS 3 to 4, 75 to 79 years of age with PS 2 to 4, and ≥ 80 years of age with PS 1 to 4) who had EGFR mutations examined by the peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp method were enrolled and received gefitinib (250 mg/d) alone. Results Between February 2006 and May 2007, 30 patients with NSCLC and poor PS, including 22 patients with PS 3 to 4, were enrolled. The overall response rate was 66% (90% CI, 51% to 80%), and the disease control rate was 90%. PS improvement rate was 79% (P < .00005); in particular, 68% of the 22 patients improved from ≥ PS 3 at baseline to ≤ PS 1. The median progression-free survival, median survival time, and 1-year survival rate were 6.5 months, 17.8 months, and 63%, respectively. No treatment-related deaths were observed. Conclusion This is the first report indicating that EGFR mutation-positive patients with extremely poor PS benefit from first-line gefitinib. Because there previously has been no standard treatment for these patients with short life expectancy other than best supportive care, examination of EGFR mutations as a biomarker is recommended in this patient population.


2009 ◽  
Vol 27 (16) ◽  
pp. 2653-2659 ◽  
Author(s):  
Hua Bai ◽  
Li Mao ◽  
hang Shu Wang ◽  
Jun Zhao ◽  
Lu Yang ◽  
...  

Purpose Mutations in the epidermal growth factor receptor (EGFR) kinase domain can predict tumor response to tyrosine kinase inhibitors (TKIs) in non–small-cell lung cancer (NSCLC). However, obtaining tumor tissues for mutation analysis is challenging. We hypothesized that plasma-based EGFR mutation analysis is feasible and has value in predicting tumor response in patients with NSCLC. Patients and Methods Plasma DNA samples and matched tumors from 230 patients with stages IIIB to IV NSCLC were analyzed for EGFR mutations in exons 19 and 21 by using denaturing high-performance liquid chromatography. We compared the mutations in the plasma samples and the matched tumors and determined an association between EGFR mutation status and the patients' clinical outcomes prospectively. Results In 230 patients, we detected 81 EGFR mutations in 79 (34.3%) of the patients' plasma samples. We detected the same mutations in 63 (79.7%) of the matched tumors. Sixteen plasma (7.0%) and fourteen tumor (6.1%) samples showed unique mutations. The mutation frequencies were significantly higher in never-smokers and in patients with adenocarcinomas (P = .012 and P = .009, respectively). In the 102 patients who failed platinum-based treatment and who were treated with gefitinib, 22 (59.5%) of the 37 with EGFR mutations in the plasma samples, whereas only 15 (23.1%) of the 65 without EGFR mutations, achieved an objective response (P = .002). Patients with EGFR mutations had a significantly longer progression-free survival time than those without mutations (P = .044) in plasma. Conclusion EGFR mutations can be reliably detected in plasma DNA of patients with stages IIIB to IV NSCLC and can be used as a biomarker to predict tumor response to TKIs.


2021 ◽  
Author(s):  
Showkat Mir ◽  
Ganesh Chandra Dash ◽  
Kumar Sambhav Chopdar ◽  
Prajna Mohanta ◽  
Pranab Kishor Mohapatra ◽  
...  

Epidermal growth factor receptor tyrosine kinase (EGFR-TK) is one of the key regulators that exhibit pivotal role in proliferation of cancer cell. Quinazolinones are studiedly widely as effective EGFR-TK inhibitor because of their higher affinity to bind with adenosine triphosphate (ATP) binding site of receptor tyrosine kinases. However, their toxicity due to non-specific binding to tyrosine kinase in non-cancerous normally dividing cells of the body limits its applicability as a cancer therapeutics. In the present investigation a series of thirty-four novel synthesized thiazolo- [2, 3-b] quinazolinones were studied in silico as EGFR-TK inhibitors. All the thirty-four compounds were screened against EGFR-TK domain using multiple software’s (AutoDock Vina, Argus Lab, YASARA, and MOE). The interactions of the ligands with amino acid residues, namely, Lys721, Met769 and Asp831 of the active site were through the functional groups on aryl substituents at position 3 and 5 of the thiazolo- [2, 3-b] quinazolinone scaffold. The methyl substituents at position 8 of the ligands had prominent hydrophobic interactions in the active site cavity of EGFR-TK domain. The compounds 5ab, 5aq, and 5bq were predicted to be non-toxic and drug-like by in silico ADMET investigations. These compounds were considered for further investigation due to their non-toxicity and higher docking score ranking in different docking methods. The molecular dynamics (MD) simulation for 100 ns of docked complexes revealed the stability of these compounds. The binding free energy determined using Molecular Mechanics Generalized Born Model and Solvent Accessibility (MM-GBSA) method indicate that thiazolo- [2, 3-b] quinazolinone has high inhibitory efficacy similar to the standard drug, erlotinib (5ab - 22.45, 5aq -22.23, 5bq -20.76, and erlotinib -24.11 kcal/mol). In silico studies and MD simulations indicated that compounds (5ab, 5aq and 5bq) could be potential EGFR-TK inhibitors and require further validation as cancer therapeutics using carcinoma cell lines.<br><p></p>


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