Cook Group

Cook Group
Cook Group
Simon Cook
Institute Director
Cook Group

Research Summary

One of the keys to understanding lifelong health is to understand the signalling pathways that operate inside cells and govern key fate decisions such as cell death, cell survival, cell division or cell senescence (collectively cell longevity).  These signalling pathways involve enzymes called ‘protein kinases’ that attach phosphate groups to specific cellular proteins, thereby controlling their activity, location or abundance. In this way protein kinases orchestrate the cellular response to growth factors, nutrient availability or stress and damage.

Ageing results in part from the imbalance between cellular damage, accrued throughout life, and the progressive decline in stress response and repair pathways. We are interested in how protein kinases function in stress responses, the removal of damaged cellular components (e.g. autophagy, see also Nicholas Ktistakis and Oliver Florey) and the control of cellular lifespan. We believe this will enhance our understanding of how the normal declines in these processes drive ageing.

Signalling pathways are frequently de-regulated in certain age-related diseases – notably in cancer, inflammation and neurodegeneration – and many protein kinases are attractive drug targets. Consequently we translate our basic knowledge of signalling through collaborations with charities and pharmaceutical companies (e.g. AstraZeneca and MISSION Therapeutics).

Latest Publications

Weatherdon L, Stuart K, Cassidy MA, de la Gándara AM, Okkenhaug H, Muellener M, Mckenzie G, Cook SJ, Gilley R Signalling, Imaging

The RAS-regulated RAF-MEK1/2-ERK1/2 signalling pathway is activated in cancer due to mutations in RAS proteins (especially KRAS), BRAF, CRAF, MEK1 and MEK2. Whilst inhibitors of KRASG12C (lung adenocarcinoma) and BRAF and MEK1/2 (melanoma and colorectal cancer) are clinically approved, acquired resistance remains a problem. Consequently, the search for new inhibitors (especially of RAS proteins), new inhibitor modalities and regulators of this pathway, which may be new drug targets, continues and increasingly involves cell-based screens with small molecules or genetic screens such as RNAi, CRISPR or Protein Interference. Here we describe cell lines that exhibit doxycycline-dependent expression KRASG12V or BRAFV600E and harbour a stably integrated EGR1:EmGFP reporter gene that can be detected by flow cytometry, high-content microscopy or immunoblotting. KRASG12V or BRAFV600E-driven EmGFP expression is inhibited by MEK1/2 or ERK1/2 inhibitors (MEKi and ERKi). BRAFi inhibit BRAFV600E-driven EmGFP expression but enhance the response to KRASG12V, recapitulating paradoxical activation of wild type RAF proteins. In addition to small molecules, expression of iDab6, encoding a RAS-specific antibody fragment inhibited KRASG12V- but not BRAFV600E-driven EmGFP expression. Finally, substitution of EmGFP for a bacterial nitroreductase gene allowed KRASG12V or BRAFV600E to drive cell death in the presence of a pro-drug, which may allow selection of pathway inhibitors that promote survival. These cell lines should prove useful for cell-based screens to identify new regulators of KRAS- or BRAF-dependent ERK1/2 signalling (drug target discovery) as well as screening or triaging 'hits' from drug discovery screens.

+view abstract The Biochemical journal, PMID: 38381045 21 Feb 2024

Park AY, Leney-Greene M, Lynberg M, Gabrielski JQ, Xu X, Schwarz B, Zheng L, Balasubramaniyam A, Ham H, Chao B, Zhang Y, Matthews HF, Cui J, Yao Y, Kubo S, Chanchu JM, Morawski AR, Cook SA, Jiang P, Ravell JC, Cheng YH, George A, Faruqi A, Pagalilauan AM, Bergerson JRE, Ganesan S, Chauvin SD, Aluri J, Edwards-Hicks J, Bohrnsen E, Tippett C, Omar H, Xu L, Butcher GW, Pascall J, Karakoc-Aydiner E, Kiykim A, Maecker H, Tezcan İ, Esenboga S, Heredia RJ, Akata D, Tekin S, Kara A, Kuloglu Z, Unal E, Kendirli T, Dogu F, Karabiber E, Atkinson TP, Cochet C, Filhol O, Bosio CM, Davis MM, Lifton RP, Pearce EL, Daumke O, Aytekin C, Şahin GE, Aksu AÜ, Uzel G, Koneti Rao V, Sari S, Boztug K, Cagdas D, Haskologlu S, Ikinciogullari A, Schwefel D, Vilarinho S, Baris S, Ozen A, Su HC, Lenardo MJ Immunology

Preserving cells in a functional, non-senescent state is a major goal for extending human healthspans. Model organisms reveal that longevity and senescence are genetically controlled, but how genes control longevity in different mammalian tissues is unknown. Here, we report a new human genetic disease that causes cell senescence, liver and immune dysfunction, and early mortality that results from deficiency of GIMAP5, an evolutionarily conserved GTPase selectively expressed in lymphocytes and endothelial cells. We show that GIMAP5 restricts the pathological accumulation of long-chain ceramides (CERs), thereby regulating longevity. GIMAP5 controls CER abundance by interacting with protein kinase CK2 (CK2), attenuating its ability to activate CER synthases. Inhibition of CK2 and CER synthase rescues GIMAP5-deficient T cells by preventing CER overaccumulation and cell deterioration. Thus, GIMAP5 controls longevity assurance pathways crucial for immune function and healthspan in mammals.

+view abstract Nature immunology, PMID: 38172257 Feb 2024

Balmanno K, Kidger AM, Byrne DP, Sale MJ, Nassman N, Eyers PA, Cook SJ Signalling

Innate or acquired resistance to small molecule BRAF or MEK1/2 inhibitors (BRAFi or MEKi) typically arises through mechanisms that sustain or reinstate ERK1/2 activation. This has led to the development of a range of ERK1/2 inhibitors (ERKi) that either inhibit kinase catalytic activity (catERKi) or additionally prevent the activating pT-E-pY dual phosphorylation of ERK1/2 by MEK1/2 (dual-mechanism or dmERKi).  Here we show that eight different ERKi (both catERKi or dmERKi) drive the turnover of ERK2, the most abundant ERK isoform, with little or no effect on ERK1.  Thermal stability assays show that ERKi do not destabilise ERK2 (or ERK1) in vitro, suggesting that ERK2 turnover is a cellular consequence of ERKi binding.  ERK2 turnover is not observed upon treatment with MEKi alone, suggesting it is ERKi binding to ERK2 that drives ERK2 turnover. However, MEKi pre-treatment, which blocks ERK2 pT-E-pY phosphorylation and dissociation from MEK1/2, prevents ERK2 turnover.  ERKi treatment of cells drives the poly-ubiquitylation and proteasome-dependent turnover of ERK2 and pharmacological or genetic inhibition of Cullin-RING E3 ligases prevents this. Our results suggest that ERKi, including current clinical candidates, act as 'kinase degraders', driving the proteasome-dependent turnover of their major target, ERK2. This may be relevant to the suggestion of kinase-independent effects of ERK1/2 and the therapeutic use of ERKi.

+view abstract The Biochemical journal, PMID: 37018014 05 Apr 2023

bioRxiv Manuscripts

DNA REPLICATION DURING ACUTE MEK INHIBITION DRIVES ACQUISITION OF RESISTANCE THROUGH AMPLIFICATION OF THE BRAF ONCOGENE

Prasanna Channathodiyil, Anne Segonds-Pichon, Paul D. Smith, Simon J. Cook, Jonathan Houseley

bioRxiv 2021.03.23.436572

https://doi.org/10.1101/2021.03.23.436572

Group Members

Simon Cook

Institute Director

Kathryn Balmanno

Senior Research Scientist

Suzan Ber

Senior Research Scientist

Anna Clay

Visiting Student

Frazer Cook

PhD Student

Rebecca Gilley

Senior Research Associate

Eleanor Griffiths

PhD Student

Laura Weatherdon

PhD Student