Epidermal growth factor receptor after 40 years

09 - 10 December 2024 09:00 - 17:00 The Royal Society Free Watch online
Stylized image of a dimer of the intact epidermal growth factor (EGF) receptor induced by binding of EGF (red) in a stylized representation of a lipid bilayer

Discussion meeting organised by Professor Mark A Lemmon FRS.

Sequencing of the epidermal growth factor receptor (EGFR) 40 years ago revealed how oncogenic viruses hijack cell growth control processes in cancer. We are only now beginning to understand the complexity of signalling by EGFR and its relatives and how best to target them in cancers. This meeting will illuminate exciting new perspectives on EGFR signalling in health and disease.

Poster session

There will be a poster session on Monday 09 December. If you would like to present a poster, please submit your proposed title, abstract (up to 200 words), author list, and the name of the proposed presenter and institution to the Scientific Programmes team no later than Friday 08 November 2024.  

Attending the meeting

This event is intended for researchers in relevant fields.

  • Free to attend
  • Both in-person and online attendance available. Advance registration is essential. Please follow the link to register
  • Lunch is available on both days of the meeting for an optional £25 per day. There are plenty of places to eat nearby if you would prefer to purchase food offsite. Participants are welcome to bring their own lunch to the meeting

Enquiries: Scientific Programmes team

Organisers

  • Professor Mark A Lemmon FRS, Yale University School of Medicine, USA

    Professor Mark A Lemmon FRS, Yale University School of Medicine, USA

    Mark Lemmon is the Alfred Gilman Professor and Chair of Pharmacology at Yale University, where he also serves as Co-Director of the Yale Cancer Biology Institute. His laboratory focuses on mechanistic, structural and biochemical aspects of signalling by growth factor receptor tyrosine kinases such as the EGF receptor, and on mechanism-guided targeted therapy in cancer in collaboration with clinicians. Educated in Oxford, UK (BA Hons in biochemistry), Yale (PhD in Molecular Biophysics and Biochemistry) and New York University (postdoc in pharmacology), he began his independent career as Assistant Professor of Biochemistry and Biophysics at the University of Pennsylvania Perelman School of Medicine, rising to full Professor and then department chair. After almost 20 years at Penn, Dr Lemmon moved to Yale in 2016 to initiate and co-direct the new Yale Cancer Biology Institute on Yale’s West Campus, and was appointed chair of Pharmacology at Yale in 2023.

Schedule

Chair

Professor Mark A Lemmon FRS, Yale University School of Medicine, USA

Professor Mark A Lemmon FRS, Yale University School of Medicine, USA

09:00-09:05 Welcome by the Royal Society and lead organiser
09:05-09:30 The challenge of curing cancer by targeting major driver oncogenes EGFR and RAS

Forty years ago, the intersection of studies of acutely transforming retroviruses and normal growth regulatory proteins led to the identification of major driver oncogenes responsible for causing a large proportion of human cancers, such as EGFR and RAS. Subsequent studies showed that these lay in the same signalling pathway, along with other major oncogenes such as BRAF, and suggested that they would make excellent targets for therapeutic intervention in oncology. EGFR inhibitory drugs have been approved for clinical use for over 20 years, but initially suffered from rapid evolution of drug resistance. Subsequent generations of EGFR inhibitors, such as osimertinib, have reduced but not eliminated this problem. RAS inhibitors took much longer to develop, gaining clinical approval in 2021, but are still plagued by rapid evolution of drug resistance, with currently licenced RAS inhibitory drugs failing to extend overall survival in lung cancer patients, although providing short-term benefit. At the start of this journey of discovery, it was assumed that removing the driver of tumour growth would result in cancer elimination, but this has turned out not to be the case. This has led to great interest in combining oncogene inhibitors with other modalities to improve the durability of responses. Oncogenic signalling not only promotes the proliferation and survival of cancer cells, but can also play a major role in suppressing anti-tumour immunity through several mechanisms. This provides a rationale for combination of oncogene targeted drugs with various types of immunotherapies, which will be explored further in this presentation. 

Dr Julian Downward FRS, Francis Crick Institute, UK

Dr Julian Downward FRS, Francis Crick Institute, UK

09:30-09:45 Discussion
09:45-10:15 Lessons learned from the EGF receptor about transmembrane signalling mechanisms

Together, the seminal 1979 discovery that EGF stimulates in vitro phosphorylation of a 170 kDa membrane protein, the presumptive EGF receptor (EGFR), and the 1980 revelation that this protein kinase activity is specific for tyrosine revolutionised our understanding of how extracellular growth factors deliver intracellular signals, and immediately suggested how receptor tyrosine kinase (RTK) pathways might be usurped by oncogenic retroviral tyrosine kinases, such as SRC. In 1981 we showed that EGF stimulates tyrosine phosphorylation of EGFR and several other proteins in intact cells. The 1984 cloning of an EGFR cDNA provided a predicted EGFR protein sequence, which led to the demonstration that EGF treatment stimulates EGF receptor autophosphorylation on several tyrosines in vivo and also increases phosphorylation of the EGFR at Thr654 in the cytoplasmic juxtamembrane domain, a site shown to be phosphorylated by protein kinase C that downregulates EGFR kinase activity. Fifty-eight of the 90 tyrosine kinases in the human kinome are RTKs; many of these are mutated and activated in cancer. Since the early 2000s, >85 clinically approved TKIs have been developed for treating cancer, including IressaTM/gefinitinib, an EGFR inhibitor approved in 2003 for treatment of non-small cell lung cancer. The development and use of anti-phosphotyrosine antibodies for studying tyrosine phosphorylation encouraged us to generate monoclonal antibodies specific for the 1- and 3-isoforms of phosphohistidine. Our recent work using these antibodies to study histidine phosphorylation of proteins will be discussed. Our findings suggest that protein-histidine phosphorylation is perturbed in several different human cancer types, affording possible therapeutic opportunities.

Dr Tony Hunter FRS, Salk Institute, USA

Dr Tony Hunter FRS, Salk Institute, USA

10:15-10:30 Discussion
10:30-11:00 Break
11:00-11:30 When is a kinase not a kinase?

The PKC family of protein kinases have revealed many behaviours that inform us more broadly on the manner in which this class of regulator operates physiologically and in disease. This includes recent findings relating to: stalled substrate complexes, kinase specificity switching and pertinent to the presentation here, nucleotide pocket dependent conformational changes. The unexpected finding that a typical nucleotide pocket binding inhibitor of PKCa could promote/stabilize the priming phosphorylation of an otherwise unstable/poorly phosphorylated PKCa point mutant, provided compelling evidence that pocket occupation is important conformationally for the retention of these priming phosphorylations in cells, corroborating early in vitro data on sensitivity to dephosphorylation. This has impacted the interpretation of anomalous activation of the ERK pathway in response to BRaf mutant-selective inhibitors; it is also germane to pseudokinases, where many retain ATP binding capacity. In the case of the pseudokinase in the EGFR family, HER3, it has been shown that retention of ATP binding is critical for allosteric activation of HER2 through the productive asymmetric dimer. This offers opportunities for small molecule intervention as demonstrated in a hit from a library screen for HER3 binders. For PKC itself, this behaviour has stimulated investigation into the function of the penetrant PKCa mutation found in chordoid glioma. Contrary to expectations, this kinase inactive catalytic aspartate mutation (D463H) is a gain of function allele revealing a conformationally dependent effector output for PKCa and the inevitable prediction that activity drives negative feedback – more akin to a G-Protein and its ATPase activity. So when is a kinase not a kinase (as we know it)?

Professor Peter J Parker FRS, Francis Crick Institute and King's College London, UK

Professor Peter J Parker FRS, Francis Crick Institute and King's College London, UK

11:30-11:45 Discussion
11:45-12:15 Functions of EGFR in physiology and disease
Professor Maria Sibilia, Center for Cancer Research and Medical University of Vienna, Austria

Professor Maria Sibilia, Center for Cancer Research and Medical University of Vienna, Austria

12:15-12:30 Discussion

Chair

Professor Yosef Yarden, Weizmann Institute of Science, Israel

Professor Yosef Yarden, Weizmann Institute of Science, Israel

13:30-14:00 Discovering how EGF receptor signals
Professor Joseph Schlessinger, Yale University School of Medicine, USA

Professor Joseph Schlessinger, Yale University School of Medicine, USA

14:00-14:15 Discussion
14:15-14:45 Targeting the EGFR family in cancer

ErbB/EGFR family members play a role in driving the growth of a number of solid tumours. Studies on TGFa, discovered in 1978 as the second member of the EGFR ligand family, led to the concept of autocrine growth factor signalling. Therapeutic agents directed against two receptor family members, EGFR and HER2/ErbB2, show meaningful clinical benefit in a number of solid tumours including breast, lung, colorectal, gastric, head and neck, etc. Clinically approved agents can be divided into three general categories: small molecule tyrosine kinase inhibitors, monoclonal antibodies and their conjugates. Multiple laboratory studies implicate HER3/ErbB3 and HER4/ErbB4 as potential targets for drug development. Surprisingly, none of these attempts have led to an approved therapeutic agent. Despite the success of the EGFR or HER2 therapies, a number of patients will recur with metastases outside the primary tumour site. Notably several cancers including breast, lung, and melanoma frequently metastasize to the brain. Unfortunately, conventional therapies do not traverse the blood brain barrier. Novel approaches to deliver macromolecules across the blood brain barrier are being developed and show early promising clinical data that they may be successful.  

Dr Mark Sliwkowski, Denali Therapeutics Inc, USA

Dr Mark Sliwkowski, Denali Therapeutics Inc, USA

14:45-15:00 Discussion
15:00-15:30 Break
15:30-16:00 Unlocking secrets of HER heterodimers

Dr Jura will present studies from her laboratory describing application of structural biology methods including X-ray crystallography and cryo-electron microscopy (cryo-EM) towards obtaining high resolution structures of human epidermal growth factor receptor (HER) tyrosine kinase signalling complexes. She will also discuss implications of these studies for signalling and therapeutic targeting. Her group’s research provided first structural insights into assembly of heterotypic kinase complexes between HER receptors by solving crystal structures of the EGFR/HER3 kinase domain complex in the wild type form and in the presence of HER3 oncogenic mutations. Following these findings, the Jura lab group developed methods for purification of full-length HER2 and HER3 receptors and their analysis by cryo-EM. This led to the first structure of the HER2/HER3 heterodimer, revealing its unique activation mechanism and explaining the activating effect of the most common HER2 oncogenic mutation, S310F, located in the extracellular domain. These studies also delineated structural basis for the binding of the HER2/HER3 complex to a therapeutic antibody trastuzumab (Herceptin). Most recent work from the Jura laboratory describes first cryo-EM structures of the HER4 homo- and HER2/HER4 heterodimeric complexes solved in the context of nearly full-length receptors. These studies shed light on the mechanisms of activation of these complexes by different growth factors and highlight presence of elaborate glycosylation modifications on HER4.

Professor Natalia Jura, University of California San Francisco, USA

Professor Natalia Jura, University of California San Francisco, USA

16:00-16:15 Discussion
16:15-17:00 Poster flash talk session

Poster flash talk session on recent developments in EGFR targeting. Moderated by Dr Tiki Hayes.

Dr Tiki Hayes, University of California, USA

Dr Tiki Hayes, University of California, USA

17:00-18:00 Poster session

Chair

Professor Marisa Martin-Fernandez, Rutherford Appleton Laboratory, UK

Professor Marisa Martin-Fernandez, Rutherford Appleton Laboratory, UK

09:00-09:30 The generation of ligand-dependent differential outputs by the epidermal growth factor receptor

The epidermal growth factor receptor (EGFR) binds to different high-affinity ligands, such as EGF and TGF-α, initiating intracellular signalling that is subtly different. Cryo-EM analyses reveal that EGFR adopts similar dimeric conformations when bound to these ligands, but with differences in conformational variability. EGF and TGF-α appear to differ in their ability to maintain a specific conformation correlated with increased EGFR activity, particularly when an oncogenic mutation is present. This study suggests a molecular mechanism by which EGFR produces different responses depending on the bound high-affinity ligand.

Professor John Kuriyan ForMemRS, Vanderbilt University School of Medicine, USA

Professor John Kuriyan ForMemRS, Vanderbilt University School of Medicine, USA

09:30-09:45 Discussion
09:45-10:15 Understanding GDNF-dependent neurotrophic signalling assembles

GDNF is made by glial cells in response to aging, damage and inflammation leading to neuroprotection by activation the RET receptor tyrosine kinase. GDNF also plays a key role in the developing enteric nervous system development and in kidney morphogenesis. The molecular mechanisms underpinning these distinct roles are not yet clear. GDNF acts with its GFRa1 co-receptor to signal through RET but can also engage the adhesion receptor NCAM and the proteoglycan syndecan-3. Structural efforts to understand these distinct GDNF-driven assemblies and their signalling outputs are revealing a surprising complexity. Recent structures will be presented together with efforts to develop GDNF mimetics as a new therapeutic modality.

Professor Neil Q McDonald, The Francis Crick Institute, UK

Professor Neil Q McDonald, The Francis Crick Institute, UK

10:15-10:30 Discussion
10:30-11:00 Break
11:00-11:30 The C elegans EGFR is a missing link that unifies EGFR and IR family activation mechanisms

It is generally accepted that ligand-induced dimerization is a key element in the activation of human EGFR. Nonetheless, there is evidence that unliganded dimers and/or oligomers of the receptor are relevant for EGFR activation at the cell surface. The precise role of these unliganded dimers is unclear, however, and none has been visualised structurally. Interestingly, unlike human EGFR, the Caenorhabditis elegans EGFR orthologue (LET-23) is always dimeric, even in the absence of ligand. It is clear that LET-23 activation is dependent on binding of its ligand (LIN-3), but activation appears to occur without alteration in the oligomeric state of the receptor – a situation that is also well known for the insulin receptor. Cryo-electron microscopy was used to determine the structure of the LET-23 extracellular region with- and without bound LIN-3, providing the first structural view of ligand-induced conformational changes within a pre-formed EGFR family dimer. In the unliganded dimer, unexpected interactions involving the C-terminal region hold the two intracellular kinase domains apart, preventing their allosteric activation. Ligand binding destabilises these interactions to allow the C-terminal legs to come together, which would allow activation of the intracellular kinase domains. Consistent with an autoinhibitory role for these C-terminal interactions, in vivo C elegans experiments show that weakening these interactions sensitises the receptor to its ligand.  Our model for LET-23 activation has striking similarities to current models for insulin receptor activation, consistent with the similarities of their N-terminal ligand binding modules and modes of ligand binding.

Dr Kathryn Ferguson, Yale University School of Medicine, USA

Dr Kathryn Ferguson, Yale University School of Medicine, USA

11:30-11:45 Discussion
11:45-12:15 From structure and mechanism to medicine: an allosteric inhibitor for EGFR L858R+ lung cancer

Mutations in the epidermal growth factor receptor (EGFR) are a common cause of non-small cell lung cancer. While osimertinib is highly efficacious in lung cancers with sensitising mutations in EGFR, there is a major unmet need for agents that overcome resistance to it and other covalent third-generation EGFR TKIs due to the C797S mutation. Furthermore, osimertinib extends overall survival in patients with exon19 deletions but offers no improvement in overall survival in patients with the L858R mutation relative to the first-generation inhibitors. Building on structural and mechanistic insights into the mechanism of EGFR regulation, we discovered allosteric inhibitors that bind the kinase in a manner that blocks its activity and disrupts formation of the activating asymmetric dimer. EAI-432 is a mutant-selective allosteric inhibitor that is effective against L858R and its common resistance variants, including T790M and C797S, while sparing WT EGFR. We are developing EAI-432 with the goal of improving outcomes for patients with EGFRL858R+ lung cancer. The compound is brain-penetrant and induces tumour regressions in multiple xenograft models at low doses (5-25 mg/kg). EAI-432 co-binds with osimertinib, allowing double-drugging of the mutant receptor. The distinct binding site and allosteric mechanism of EAI-432 confer exquisite kinome-wide selectivity and orthogonal resistance mechanisms as compared with osimertinib and other ATP-competitive TKIs, properties that are highly desirable in a combination agent. The compound has efficacy, mutant-selectivity, and pharmacokinetic properties that support its further development as a therapeutic agent for EGFRL858R+ lung cancer alone or in combination with osimertinib.

Professor Michael J Eck, Harvard Medical School, USA

Professor Michael J Eck, Harvard Medical School, USA

12:15-12:30 Discussion

Chair

Professor Katerina Politi, Yale Cancer Center and Yale School of Medicine, USA

Professor Katerina Politi, Yale Cancer Center and Yale School of Medicine, USA

13:30-14:00 Twenty years of progress in treating lung cancer with EGFR inhibitors
Professor Roy S Herbst, Yale School of Medicine, USA

Professor Roy S Herbst, Yale School of Medicine, USA

14:00-14:15 Discussion
14:15-14:45 Personalising EGFR-targeted cancer therapy
Dr Christine M Lovly, Vanderbilt University Medical Center and Vanderbilt Ingram Cancer Center, USA

Dr Christine M Lovly, Vanderbilt University Medical Center and Vanderbilt Ingram Cancer Center, USA

14:45-15:00 Discussion
15:00-15:30 Break
15:30-16:00 Air pollutants promote non-small cell lung carcinogenesis

A mechanistic basis for non-small cell lung cancer (NSCLC) initiation in never smokers, a disease with high frequency EGFR mutations (EGFRm), is unclear. Air pollution particulate matter (PM) is known to be associated with the risk of NSCLC, however a direct cause and mechanism remain elusive. We analysed 463,679 individuals to address the associations of increasing 2.5um PM (PM2.5) concentrations with cancer risk. We performed ultra-deep profiling of 247 normal lung tissue samples, analysed normal lung tissue from humans and mice following exposures to PM, and investigated the consequences of PM in mouse lung cancer models. Increasing PM2.5 levels are associated with increased risk of EGFRm NSCLC in England, South Korea and Taiwan. 18-33% of normal lung tissue samples harbour driver mutations in EGFR and KRAS in the absence of malignancy. PM promotes a macrophage response and a progenitor-like state in lung epithelium harbouring mutant EGFR. Consistent with PM promoting NSCLC in at-risk epithelium harbouring driver mutations, PM accelerates tumourigenesis in three EGFR or KRAS driven lung cancer models in a dose-dependent manner. Finally, we uncover an actionable inflammatory axis driven by IL1B in response to PM, in agreement with reductions in lung cancer incidence with anti-IL1ß therapy. These results shed light on the etiology of EGFRm lung cancer and suggest that oncogenic mutations may be necessary but insufficient for tumour formation. These data reveal a mechanistic basis for PM driven lung cancer providing an urgent mandate to limit air pollution. Importantly, the observation of a reduction in pollution-induced tumour growth upon anti-IL1ß treatment suggested that tumorigenesis may be prevented.

Assistant Professor Emilia Lim, The University of British Columbia, Canada

Assistant Professor Emilia Lim, The University of British Columbia, Canada

16:00-16:15 Discussion
16:15-17:00 Panel discussion

Panel discussion with Professor Daniel J Leahy, Associate Professor Chiara Francavilla, Professor Daniel Hochhauser and Professor Linda J Pike.

Professor Daniel J Leahy, University of Texas at Austin, USA

Professor Daniel J Leahy, University of Texas at Austin, USA

Associate Professor Chiara Francavilla, Technical University of Denmark, Denmark, and The University of Manchester, UK

Associate Professor Chiara Francavilla, Technical University of Denmark, Denmark, and The University of Manchester, UK

Professor Daniel Hochhauser, University College London Cancer Institute, UK

Professor Daniel Hochhauser, University College London Cancer Institute, UK

Professor Linda J Pike, Washington University in St Louis, USA

Professor Linda J Pike, Washington University in St Louis, USA