Chessum, N.E., Sharp, S.Y., Caldwell, J.J., Pasqua, A.E., Wilding, B., Colombano, G., Collins, I., Ozer, B., Richards, M., Rowlands, M., et al.
(2018). Demonstrating In-Cell Target Engagement Using a Pirin Protein Degradation Probe (CCT367766). J med chem,
Demonstrating intracellular protein target engagement is an essential step in the development and progression of new chemical probes and potential small molecule therapeutics. However, this can be particularly challenging for poorly studied and noncatalytic proteins, as robust proximal biomarkers are rarely known. To confirm that our recently discovered chemical probe 1 (CCT251236) binds the putative transcription factor regulator pirin in living cells, we developed a heterobifunctional protein degradation probe. Focusing on linker design and physicochemical properties, we generated a highly active probe 16 (CCT367766) in only three iterations, validating our efficient strategy for degradation probe design against nonvalidated protein targets..
Meyers, J., Chessum, N.E., Ali, S., Mok, N.Y., Wilding, B., Pasqua, A.E., Rowlands, M., Tucker, M.J., Evans, L.E., Rye, C.S., et al.
(2018). Privileged Structures and Polypharmacology within and between Protein Families. Acs med chem lett,
Polypharmacology is often a key contributor to the efficacy of a drug, but is also a potential risk. We investigated two hits discovered via a cell-based phenotypic screen, the CDK9 inhibitor CCT250006 (1) and the pirin ligand CCT245232 (2), to establish methodology to elucidate their secondary protein targets. Using computational pocket-based analysis, we discovered intrafamily polypharmacology for our kinase inhibitor, despite little overall sequence identity. The interfamily polypharmacology of 2 with B-Raf was used to discover a novel pirin ligand from a very small but privileged compound library despite no apparent ligand or binding site similarity. Our data demonstrates that in areas of drug discovery where intrafamily polypharmacology is often an issue, ligand dissimilarity cannot necessarily be used to assume different off-target profiles and that understanding interfamily polypharmacology will be important in the future to reduce the risk of idiopathic toxicity and in the design of screening libraries..
Fearon, D., Westwood, I.M., van Montfort, R.L., Bayliss, R., Jones, K. & Bavetsias, V.
(2018). Synthesis and profiling of a 3-aminopyridin-2-one-based kinase targeted fragment library: Identification of 3-amino-5-(pyridin-4-yl)pyridin-2(1H)-one scaffold for monopolar spindle 1 (MPS1) and Aurora kinases inhibition. Bioorg med chem,
Screening a 3-aminopyridin-2-one based fragment library against a 26-kinase panel representative of the human kinome identified 3-amino-5-(1-methyl-1H-pyrazol-4-yl)pyridin-2(1H)-one (2) and 3-amino-5-(pyridin-4-yl)pyridin-2(1H)-one (3) as ligand efficient inhibitors of the mitotic kinase Monopolar Spindle 1 (MPS1) and the Aurora kinase family. These kinases are well recognised as attractive targets for therapeutic intervention for treating cancer. Elucidation of the binding mode of these fragments and their analogues has been carried out by X-ray crystallography. Structural studies have identified key interactions with a conserved lysine residue and have highlighted potential regions of MPS1 which could be targeted to improve activity and selectivity..
Fok, J.H., Hedayat, S., Zhang, L., Aronson, L.I., Mirabella, F., Pawlyn, C., Bright, M.D., Wardell, C.P., Keats, J.J., De Billy, E., et al.
(2018). HSF1 Is Essential for Myeloma Cell Survival and A Promising Therapeutic Target. Clin cancer res,
Purpose: Myeloma is a plasma cell malignancy characterized by the overproduction of immunoglobulin, and is therefore susceptible to therapies targeting protein homeostasis. We hypothesized that heat shock factor 1 (HSF1) was an attractive therapeutic target for myeloma due to its direct regulation of transcriptional programs implicated in both protein homeostasis and the oncogenic phenotype. Here, we interrogate HSF1 as a therapeutic target in myeloma using bioinformatic, genetic, and pharmacologic means.Experimental Design: To assess the clinical relevance of HSF1, we analyzed publicly available patient myeloma gene expression datasets. Validation of this novel target was conducted in in vitro experiments using shRNA or inhibitors of the HSF1 pathway in human myeloma cell lines and primary cells as well as in in vivo human myeloma xenograft models.Results: Expression of HSF1 and its target genes were associated with poorer myeloma patient survival. ShRNA-mediated knockdown or pharmacologic inhibition of the HSF1 pathway with a novel chemical probe, CCT251236, or with KRIBB11, led to caspase-mediated cell death that was associated with an increase in EIF2α phosphorylation, CHOP expression and a decrease in overall protein synthesis. Importantly, both CCT251236 and KRIBB11 induced cytotoxicity in human myeloma cell lines and patient-derived primary myeloma cells with a therapeutic window over normal cells. Pharmacologic inhibition induced tumor growth inhibition and was well-tolerated in a human myeloma xenograft murine model with evidence of pharmacodynamic biomarker modulation.Conclusions: Taken together, our studies demonstrate the dependence of myeloma cells on HSF1 for survival and support the clinical evaluation of pharmacologic inhibitors of the HSF1 pathway in myeloma. Clin Cancer Res; 24(10); 2395-407. ©2018 AACRSee related commentary by Parekh, p. 2237..
Evans, L.E., Jones, K. & Cheeseman, M.D.
(2017). Targeting secondary protein complexes in drug discovery: studying the druggability and chemical biology of the HSP70/BAG1 complex. Chem commun (camb),
Proteins typically carry out their biological functions as multi-protein complexes, which can significantly affect the affinity of small-molecule inhibitors. HSP70 is an important target in oncology, so to study its chemical biology and the drug discovery potential of the HSP70/BAG1 complex, we designed a high-affinity non-nucleotide fluorescence polarisation probe..
Stork, G., Yamashita, A., Hanson, R.M., Phan, L., Phillips, E., Dubé, D., Bos, P.H., Clark, A.J., Gough, M., Greenlee, M.L., et al.
(2017). Synthetic Study toward Total Synthesis of (±)-Germine: Synthesis of (±)-4-Methylenegermine. Org lett,
The total synthesis of 4-methylenegermine is described..
Cheeseman, M.D., Chessum, N.E., Rye, C.S., Pasqua, A.E., Tucker, M.J., Wilding, B., Evans, L.E., Lepri, S., Richards, M., Sharp, S.Y., et al.
(2017). Discovery of a Chemical Probe Bisamide (CCT251236): An Orally Bioavailable Efficacious Pirin Ligand from a Heat Shock Transcription Factor 1 (HSF1) Phenotypic Screen. J med chem,
Phenotypic screens, which focus on measuring and quantifying discrete cellular changes rather than affinity for individual recombinant proteins, have recently attracted renewed interest as an efficient strategy for drug discovery. In this article, we describe the discovery of a new chemical probe, bisamide (CCT251236), identified using an unbiased phenotypic screen to detect inhibitors of the HSF1 stress pathway. The chemical probe is orally bioavailable and displays efficacy in a human ovarian carcinoma xenograft model. By developing cell-based SAR and using chemical proteomics, we identified pirin as a high affinity molecular target, which was confirmed by SPR and crystallography..
Pettinger, J., Le Bihan, Y.-., Widya, M., van Montfort, R.L., Jones, K. & Cheeseman, M.D.
(2017). An Irreversible Inhibitor of HSP72 that Unexpectedly Targets Lysine-56. Angew chem int ed engl,
The stress-inducible molecular chaperone, HSP72, is an important therapeutic target in oncology, but inhibiting this protein with small molecules has proven particularly challenging. Validating HSP72 inhibitors in cells is difficult owing to competition with the high affinity and abundance of its endogenous nucleotide substrates. We hypothesized this could be overcome using a cysteine-targeted irreversible inhibitor. Using rational design, we adapted a validated 8-N-benzyladenosine ligand for covalent bond formation and confirmed targeted irreversible inhibition. However, no cysteine in the protein was modified; instead, we demonstrate that lysine-56 is the key nucleophilic residue. Targeting this lysine could lead to a new design paradigm for HSP72 chemical probes and drugs..
Pettinger, J., Le Bihan, Y.-., Widya, M., van Montfort, R.L., Jones, K. & Cheeseman, M.D.
(2017). An Irreversible Inhibitor of HSP72 that Unexpectedly Targets Lysine-56. Angewandte chemie-international edition,
Pettinger, J., Jones, K. & Cheeseman, M.D.
(2017). Lysine-Targeting Covalent Inhibitors. Angew chem int ed engl,
Targeted covalent inhibitors have gained widespread attention in drug discovery as a validated method to circumvent acquired resistance in oncology. This strategy exploits small-molecule/protein crystal structures to design tightly binding ligands with appropriately positioned electrophilic warheads. Whilst most focus has been on targeting binding-site cysteine residues, targeting nucleophilic lysine residues can also represent a viable approach to irreversible inhibition. However, owing to the basicity of the ϵ-amino group in lysine, this strategy generates a number of specific challenges. Herein, we review the key principles for inhibitor design, give historical examples, and present recent developments that demonstrate the potential of lysine targeting for future drug discovery..
Rye, C.S., Chessum, N.E., Lamont, S., Pike, K.G., Faulder, P., Demeritt, J., Kemmitt, P., Tucker, J., Zani, L., Cheeseman, M.D., et al.
(2016). Discovery of 4,6-disubstituted pyrimidines as potent inhibitors of the heat shock factor 1 (HSF1) stress pathway and CDK9. Medchemcomm,
Heat shock factor 1 (HSF1) is a transcription factor that plays key roles in cancer, including providing a mechanism for cell survival under proteotoxic stress. Therefore, inhibition of the HSF1-stress pathway represents an exciting new opportunity in cancer treatment. We employed an unbiased phenotypic screen to discover inhibitors of the HSF1-stress pathway. Using this approach we identified an initial hit (1) based on a 4,6-pyrimidine scaffold (2.00 μM). Optimisation of cellular SAR led to an inhibitor with improved potency (25, 15 nM) in the HSF1 phenotypic assay. The 4,6-pyrimidine 25 was also shown to have high potency against the CDK9 enzyme (3 nM)..
Jones, A.M., Westwood, I.M., Osborne, J.D., Matthews, T.P., Cheeseman, M.D., Rowlands, M.G., Jeganathan, F., Burke, R., Lee, D., Kadi, N., et al.
(2016). A fragment-based approach applied to a highly flexible target: Insights and challenges towards the inhibition of HSP70 isoforms. Sci rep,
The heat shock protein 70s (HSP70s) are molecular chaperones implicated in many cancers and of significant interest as targets for novel cancer therapies. Several HSP70 inhibitors have been reported, but because the majority have poor physicochemical properties and for many the exact mode of action is poorly understood, more detailed mechanistic and structural insight into ligand-binding to HSP70s is urgently needed. Here we describe the first comprehensive fragment-based inhibitor exploration of an HSP70 enzyme, which yielded an amino-quinazoline fragment that was elaborated to a novel ATP binding site ligand with different physicochemical properties to known adenosine-based HSP70 inhibitors. Crystal structures of amino-quinazoline ligands bound to the different conformational states of the HSP70 nucleotide binding domain highlighted the challenges of a fragment-based approach when applied to this particular flexible enzyme class with an ATP-binding site that changes shape and size during its catalytic cycle. In these studies we showed that Ser275 is a key residue in the selective binding of ATP. Additionally, the structural data revealed a potential functional role for the ATP ribose moiety in priming the protein for the formation of the ATP-bound pre-hydrolysis complex by influencing the conformation of one of the phosphate binding loops..
Cheeseman, M.D., Westwood, I.M., Barbeau, O., Rowlands, M., Dobson, S., Jones, A.M., Jeganathan, F., Burke, R., Kadi, N., Workman, P., et al.
(2016). Exploiting Protein Conformational Change to Optimize Adenosine-Derived Inhibitors of HSP70. J med chem,
HSP70 is a molecular chaperone and a key component of the heat-shock response. Because of its proposed importance in oncology, this protein has become a popular target for drug discovery, efforts which have as yet brought little success. This study demonstrates that adenosine-derived HSP70 inhibitors potentially bind to the protein with a novel mechanism of action, the stabilization by desolvation of an intramolecular salt-bridge which induces a conformational change in the protein, leading to high affinity ligands. We also demonstrate that through the application of this mechanism, adenosine-derived HSP70 inhibitors can be optimized in a rational manner..
Rye, C.S., Chessum, N.E., Lamont, S., Pike, K.G., Faulder, P., Demeritt, J., Kemmitt, P., Tucker, J., Zani, L., Cheeseman, M.D., et al.
(2016). Discovery of 4,6-disubstituted pyrimidines as potent inhibitors of the heat shock factor 1 (HSF1) stress pathway and CDK9 (vol 7, pg 1580, 2016). Medchemcomm,
Robinson, C.W., Rye, C.S., Chessum, N.E. & Jones, K.
(2015). A model β-sheet interaction and thermodynamic analysis of β-strand mimetics. Org biomol chem,
β-Sheet mediated protein-protein interactions are involved in key signalling pathways in diseases such as cancer. We present small molecule β-strand mimetics and investigate their interactions with a model tripeptide. Using (1)H NMR, the thermodynamic parameters for their binding are determined. These give insight into this biologically important interaction. .
Andrikopoulos, P., Kieswich, J., Harwood, S.M., Baba, A., Matsuda, T., Barbeau, O., Jones, K., Eccles, S.A. & Yaqoob, M.M.
(2015). Endothelial Angiogenesis and Barrier Function in Response to Thrombin Require Ca2+ Influx through the Na+/Ca2+ Exchanger. J biol chem,
Thrombin acts on the endothelium by activating protease-activated receptors (PARs). The endothelial thrombin-PAR system becomes deregulated during pathological conditions resulting in loss of barrier function and a pro-inflammatory and pro-angiogenic endothelial phenotype. We reported recently that the ion transporter Na(+)/Ca(2+) exchanger (NCX) operating in the Ca(2+)-influx (reverse) mode promoted ERK1/2 activation and angiogenesis in vascular endothelial growth factor-stimulated primary human vascular endothelial cells. Here, we investigated whether Ca(2+) influx through NCX was involved in ERK1/2 activation, angiogenesis, and endothelial barrier dysfunction in response to thrombin. Reverse-mode NCX inhibitors and RNAi-mediated NCX1 knockdown attenuated ERK1/2 phosphorylation in response to thrombin or an agonist of PAR-1, the main endothelial thrombin receptor. Conversely, promoting reverse-mode NCX by suppressing Na(+)-K(+)-ATPase activity enhanced ERK1/2 activation. Reverse-mode NCX inhibitors and NCX1 siRNA suppressed thrombin-induced primary human vascular endothelial cell angiogenesis, quantified as proliferation and tubular differentiation. Reverse-mode NCX inhibitors or NCX1 knockdown preserved barrier integrity upon thrombin stimulation in vitro. Moreover, the reverse-mode NCX inhibitor SEA0400 suppressed Evans' blue albumin extravasation to the lung and kidneys and attenuated edema formation and ERK1/2 activation in the lungs of mice challenged with a peptide activator of PAR-1. Mechanistically, thrombin-induced ERK1/2 activation required NADPH oxidase 2-mediated reactive oxygen species (ROS) production, and reverse-mode NCX inhibitors and NCX1 siRNA suppressed thrombin-induced ROS production. We propose that reverse-mode NCX is a novel mechanism contributing to thrombin-induced angiogenesis and hyperpermeability by mediating ERK1/2 activation in a ROS-dependent manner. Targeting reverse-mode NCX could be beneficial in pathological conditions involving unregulated thrombin signaling. .
Evans, L.E., Cheeseman, M.D., Yahya, N. & Jones, K.
(2015). Investigating Apoptozole as a Chemical Probe for HSP70 Inhibition. Plos one,
The use of chemical tools to validate clinical targets has gained in popularity over recent years and the importance of understanding the activity, selectivity and mechanism of action of these compounds is well recognized. Dysregulation of the HSP70 protein family has been linked to multiple cancer types and drug resistance, highlighting their importance as popular targets for anti-cancer drug development. Apoptozole is a recently identified small molecule, which has been reported to possess strong affinity for the HSP70 isoforms HSP72 and HSC70. We investigated apoptozole as a potential chemical tool for HSP70 inhibition. Unfortunately, using both biochemical and biophysical techniques, we were unable to find any experimental evidence that apoptozole binds to HSP70 in a specific and developable way. Instead, we provide experimental evidence that apoptozole forms aggregates under aqueous conditions that could interact with HSP70 proteins in a non-specific manner. .
Cheeseman, M.D., Faisal, A., Rayter, S., Barbeau, O.R., Kalusa, A., Westlake, M., Burke, R., Swan, M., van Montfort, R., Linardopoulos, S., et al.
(2014). Targeting the PPM1D phenotype; 2,4-bisarylthiazoles cause highly selective apoptosis in PPM1D amplified cell-lines. Bioorg med chem lett,
The metal-dependent phosphatase PPM1D (WIP1) is an important oncogene in cancer, with over-expression of the protein being associated with significantly worse clinical outcomes. In this communication we describe the discovery and optimization of novel 2,4-bisarylthiazoles that phenocopy the knockdown of PPM1D, without inhibiting its phosphatase activity. These compounds cause growth inhibition at nanomolar concentrations, induce apoptosis, activate p53 and display impressive cell-line selectivity. The results demonstrate the potential for targeting phenotypes in drug discovery when tackling challenging targets or unknown mechanisms. .
Hickin, J.A., Ahmed, A., Fucke, K., Ashcroft, M. & Jones, K.
(2014). The synthesis and structure revision of NSC-134754. Chem commun (camb),
The synthesis of emetine analogue NSC-134754, a potent inhibitor of the HIF pathway, has been accomplished and its structure reassigned. The stereochemistry of NSC-134754 has been assigned for the first time using X-ray crystallography and it has been demonstrated that only one diastereoisomer is active against HIF. .
Couty, S., Westwood, I.M., Kalusa, A., Cano, C., Travers, J., Boxall, K., Chow, C.L., Burns, S., Schmitt, J., Pickard, L., et al.
(2013). The discovery of potent ribosomal S6 kinase inhibitors by high-throughput screening and structure-guided drug design. Oncotarget,
The ribosomal P70 S6 kinases play a crucial role in PI3K/mTOR regulated signalling pathways and are therefore potential targets for the treatment of a variety of diseases including diabetes and cancer. In this study we describe the identification of three series of chemically distinct S6K1 inhibitors. In addition, we report a novel PKA-S6K1 chimeric protein with five mutations in or near its ATP-binding site, which was used to determine the binding mode of two of the three inhibitor series, and provided a robust system to aid the optimisation of the oxadiazole-substituted benzimidazole inhibitor series. We show that the resulting oxadiazole-substituted aza-benzimidazole is a potent and ligand efficient S6 kinase inhibitor, which blocks the phosphorylation of RPS6 at Ser235/236 in TSC negative HCV29 human bladder cancer cells by inhibiting S6 kinase activity and thus provides a useful tool compound to investigate the function of S6 kinases..
Silva-Santisteban, M.C., Westwood, I.M., Boxall, K., Brown, N., Peacock, S., McAndrew, C., Barrie, E., Richards, M., Mirza, A., Oliver, A.W., et al.
(2013). Fragment-based screening maps inhibitor interactions in the ATP-binding site of checkpoint kinase 2. Plos one,
Checkpoint kinase 2 (CHK2) is an important serine/threonine kinase in the cellular response to DNA damage. A fragment-based screening campaign using a combination of a high-concentration AlphaScreen™ kinase assay and a biophysical thermal shift assay, followed by X-ray crystallography, identified a number of chemically different ligand-efficient CHK2 hinge-binding scaffolds that have not been exploited in known CHK2 inhibitors. In addition, it showed that the use of these orthogonal techniques allowed efficient discrimination between genuine hit matter and false positives from each individual assay technology. Furthermore, the CHK2 crystal structures with a quinoxaline-based fragment and its follow-up compound highlight a hydrophobic area above the hinge region not previously explored in rational CHK2 inhibitor design, but which might be exploited to enhance both potency and selectivity of CHK2 inhibitors..
Evans, L.E., Cheeseman, M.D. & Jones, K.
(2012). N-N bond-forming cyclization for the one-pot synthesis of N-aryl[3,4-d]pyrazolopyrimidines. Org lett,
An efficient one-pot synthesis of N-aryl[3,4-d]pyrazolopyrimidines in good yield and under mild reaction conditions is described. By exploiting electron-deficient hydroxylamines, the substituted oxime products were formed with very high E-diastereoselectivity. The key step utilizes a cyclization reaction upon an oxime derived from hydroxylamine-O-sulfonic acid to form the N-N bond of the product..
Francis, N.-., Rowlands, M., Workman, P., Jones, K. & Aherne, W.
(2012). Small-molecule inhibitors of the protein methyltransferase SET7/9 identified in a high-throughput screen. J biomol screen,
Aberrant expression of chromatin-modifying enzymes (CMEs) is associated with a range of human diseases, including cancer. CMEs are now an important target area in drug discovery. Although the role that histone and protein (lysine) methyltransferases (PMTs) play in the regulation of transcription and cell growth is increasingly recognized, few small-molecule inhibitors of this class of enzyme have been reported. Here we describe an assay suitable for primary compound screening for the identification of PMT inhibitors. The assay followed the methylation of histones in the presence of the PMT SET7/9 and the radioactive cofactor S-adenosyl-methionine using scintillating microplates (FlashPlate) and was used to screen approximately 65 000 compounds (% coefficient of variation = 10%; Z' = 0.6). The hits identified from a library of more than 63 000 diverse small molecules included a series of rhodanine compounds with micromolar activity. A screen of the National Cancer Institute Diversity Set (2000 compounds) identified an orsein derivative that inhibited SET7/9 (~20 µM) and showed modest growth inhibition associated with the expected cellular phenotype of reduced histone methylation in a human tumor cell line. The assay represents a useful tool for the identification of inhibitors of PMT activity..
Rowlands, M., McAndrew, C., Prodromou, C., Pearl, L., Kalusa, A., Jones, K., Workman, P. & Aherne, W.
(2010). Detection of the ATPase activity of the molecular chaperones Hsp90 and Hsp72 using the TranscreenerTM ADP assay kit. J biomol screen,
The molecular chaperone heat shock protein 90 (Hsp90) is required for the correct folding and stability of a number of client proteins that are important for the growth and maintenance of cancer cells. Heat shock protein 72 (Hsp72), a co-chaperone of Hsp90, is also emerging as an attractive cancer drug target. Both proteins bind and hydrolyze adenosine triphosphate (ATP), and ATPase activity is essential for their function. Inhibition of Hsp90 ATPase activity leads to the degradation of client proteins, resulting in cell growth inhibition and apoptosis. Several small-molecule inhibitors of the ATPase activity of Hsp90 have been described and are currently being evaluated clinically for the treatment of cancer. A number of methods for the measurement of ATPase activity have been previously used, but not all of these are ideally suited to screening cascades in drug discovery projects. The authors have evaluated the use of commercial reagents (Transcreener ADP) for the measurement of ATPase activity of both yeast and human Hsp90 (ATP K(m) approximately 500 microM) and human Hsp72 (ATP K(m) ~1 microM). The low ATPase activity of human Hsp90 and its stimulation by the co-chaperone Aha1 was measured with ease using reduced incubation times, generating robust data (Z' = 0.75). The potency of several small-molecule inhibitors of both Hsp90 and Hsp72 was determined using the Transcreener reagents and compared well to that determined using other assay formats..
Jones, K. & McHardy, T.
(2010). Cancer Drug Discovery 2010: from molecules to medicine. Expert rev clin pharmacol,
This article provides an overview of a recent 1-day symposium on the current status and the future prospects for small-molecule therapeutics in oncology. Presentations included aspects of kinase inhibition, the targeting of G-quadruplexes, oxygen sensing as a therapeutic target and sulfatase inhibitors for hormone-dependent breast cancer..
Powers, M.V., Jones, K., Barillari, C., Westwood, I., van Montfort, R.L. & Workman, P.
(2010). Targeting HSP70: the second potentially druggable heat shock protein and molecular chaperone?. Cell cycle,
The HSF1-mediated stress response pathway is steadily gaining momentum as a critical source of targets for cancer therapy. Key mediators of this pathway include molecular chaperones such as heat shock protein (HSP) 90. There has been considerable progress in targeting HSP90 and the preclinical efficacy and signs of early clinical activity of HSP90 inhibitors have provided proof-of-concept for targeting this group of proteins. The HSP70 family of molecular chaperones are also key mediators of the HSF-1-stress response pathway and have multiple additional roles in protein folding, trafficking and degradation, as well as regulating apoptosis. Genetic and biochemical studies have supported the discovery of HSP70 inhibitors which have the potential for use as single agents or in combination to enhance the effects of classical chemotherapeutic or molecularly targeted agents including HSP90 inhibitors. Here we provide a perspective on the progress made so far in designing agents which target the HSP70 family..
Ahmad, N.M. & Jones, K.
(2010). An efficient synthesis of thiazolo[3,2-a]pyrimidinones. Tetrahedron lett,
A series of thiazolo[3,2-a]pyrimidinones was synthesised in a two-step procedure, using Eaton's reagent to effect cyclisation of 2-aminothiazoles. The use of relatively low temperatures, facile product isolation and short reaction times make this cyclisation procedure a particularly attractive option over more conventional methods. (C) 2010 Elsevier Ltd. All rights reserved..
Mirizzi, D., Hilton, S.T. & Jones, K.
(2010). Heteroaryl Radicals Review. Adv heterocycl chem,
Kalusa, A., Chessum, N. & Jones, K.
(2008). An efficient synthesis of 2,3-diaryl (3H)-quinazolin-4-ones via imidoyl chlorides. Tetrahedron lett,
A practical and efficient three step synthetic route to 2,3-diaryl (3H)-quinazolin-4-ones has been developed. The key step involves microwave-assisted condensation of an imidoyl chloride with an aryl amine. This methodology affords the products cleanly and in high yields. (C) 2008 Elsevier Ltd. All rights reserved..
Rayter, S., Elliott, R., Travers, J., Rowlands, M.G., Richardson, T.B., Boxall, K., Jones, K., Linardopoulos, S., Workman, P., Aherne, W., et al.
(2008). A chemical inhibitor of PPM1D that selectively kills cells overexpressing PPM1D. Oncogene,
The PPM1D gene is aberrantly amplified in a range of common cancers and encodes a protein phosphatase that is a potential therapeutic target. However, the issue of whether inhibition of PPM1D in human tumour cells that overexpress this protein compromises their viability has not yet been fully addressed. We show here, using an RNA interference (RNAi) approach, that inhibition of PPM1D can indeed reduce the viability of human tumour cells and that this effect is selective; tumour cell lines that overexpress PPM1D are sensitive to PPM1D inhibition whereas cell lines with normal levels are not. Loss of viability associated with PPM1D RNAi in human tumour cells occurs via the activation of the kinase P38. To identify chemical inhibitors of PPM1D, a high-throughput screening of a library of small molecules was performed. This strategy successfully identified a compound that selectively reduces viability of human tumour cell lines that overexpress PPM1D. As expected of a specific inhibitor, the toxicity to PPM1D overexpressing cell lines after inhibitor treatment is P38 dependent. These results further validate PPM1D as a therapeutic target and identify a proof-of-principle small molecule inhibitor..
Eccles, S.A., Massey, A., Raynaud, F.I., Sharp, S.Y., Box, G., Valenti, M., Patterson, L., de Haven Brandon, A., Gowan, S., Boxall, F., et al.
(2008). NVP-AUY922: a novel heat shock protein 90 inhibitor active against xenograft tumor growth, angiogenesis, and metastasis. Cancer res,
We describe the biological properties of NVP-AUY922, a novel resorcinylic isoxazole amide heat shock protein 90 (HSP90) inhibitor. NVP-AUY922 potently inhibits HSP90 (K(d) = 1.7 nmol/L) and proliferation of human tumor cells with GI(50) values of approximately 2 to 40 nmol/L, inducing G(1)-G(2) arrest and apoptosis. Activity is independent of NQO1/DT-diaphorase, maintained in drug-resistant cells and under hypoxic conditions. The molecular signature of HSP90 inhibition, comprising induced HSP72 and depleted client proteins, was readily demonstrable. NVP-AUY922 was glucuronidated less than previously described isoxazoles, yielding higher drug levels in human cancer cells and xenografts. Daily dosing of NVP-AUY922 (50 mg/kg i.p. or i.v.) to athymic mice generated peak tumor levels at least 100-fold above cellular GI(50). This produced statistically significant growth inhibition and/or regressions in human tumor xenografts with diverse oncogenic profiles: BT474 breast tumor treated/control, 21%; A2780 ovarian, 11%; U87MG glioblastoma, 7%; PC3 prostate, 37%; and WM266.4 melanoma, 31%. Therapeutic effects were concordant with changes in pharmacodynamic markers, including induction of HSP72 and depletion of ERBB2, CRAF, cyclin-dependent kinase 4, phospho-AKT/total AKT, and hypoxia-inducible factor-1alpha, determined by Western blot, electrochemiluminescent immunoassay, or immunohistochemistry. NVP-AUY922 also significantly inhibited tumor cell chemotaxis/invasion in vitro, WM266.4 melanoma lung metastases, and lymphatic metastases from orthotopically implanted PC3LN3 prostate carcinoma. NVP-AUY922 inhibited proliferation, chemomigration, and tubular differentiation of human endothelial cells and antiangiogenic activity was reflected in reduced microvessel density in tumor xenografts. Collectively, the data show that NVP-AUY922 is a potent, novel inhibitor of HSP90, acting via several processes (cytostasis, apoptosis, invasion, and angiogenesis) to inhibit tumor growth and metastasis. NVP-AUY922 has entered phase I clinical trials..
Hardcastle, A., Tomlin, P., Norris, C., Richards, J., Cordwell, M., Boxall, K., Rowlands, M., Jones, K., Collins, I., McDonald, E., et al.
(2007). A duplexed phenotypic screen for the simultaneous detection of inhibitors of the molecular chaperone heat shock protein 90 and modulators of cellular acetylation. Mol cancer ther,
Histone deacetylases (HDACs), histone acetyltransferases (HATs), and the molecular chaperone heat shock protein 90 (HSP90) are attractive anticancer drug targets. High-throughput screening plays a pivotal role in modern molecular mechanism-based drug discovery. Cell-based screens are particularly useful in that they identify compounds that are permeable and active against the selected target or pathway in a cellular context. We have previously developed time-resolved fluorescence cell immunosorbent assays (TRF-Cellisas) for compound screening and pharmacodynamic studies. These assays use a primary antibody to the single protein of interest and a matched secondary immunoglobulin labeled with an europium chelate (Eu). The availability of species-specific secondary antibodies labeled with different lanthanide chelates provides the potential for multiplexing this type of assay. The approach has been applied to the development of a 384-well duplexed cell-based screen to simultaneously detect compounds that induce the co-chaperone HSP70 as a molecular marker of potential inhibitors of HSP90 together with those that modulate cellular acetylation (i.e., potential inhibitors of histone deacetylase or histone acetyltransferase activity). The duplexed assay proved reliable in high-throughput format and approximately 64,000 compounds were screened. Following evaluation in secondary assays, 3 of 13 hits from the HSP70 arm were confirmed. Two of these directly inhibited the intrinsic ATPase activity of HSP90 whereas the third seems to have a different mechanism of action. In the acetylation arm, two compounds increased cellular acetylation, one of which inhibited histone deacetylase activity. A third compound decreased cellular histone acetylation, potentially through a novel mechanism of action..
Sharp, S.Y., Prodromou, C., Boxall, K., Powers, M.V., Holmes, J.L., Box, G., Matthews, T.P., Cheung, K.-., Kalusa, A., James, K., et al.
(2007). Inhibition of the heat shock protein 90 molecular chaperone in vitro and in vivo by novel, synthetic, potent resorcinylic pyrazole/isoxazole amide analogues. Mol cancer ther,
Although the heat shock protein 90 (HSP90) inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) shows clinical promise, potential limitations encourage development of alternative chemotypes. We discovered the 3,4-diarylpyrazole resorcinol CCT018159 by high-throughput screening and used structure-based design to generate more potent pyrazole amide analogues, exemplified by VER-49009. Here, we describe the detailed biological properties of VER-49009 and the corresponding isoxazole VER-50589. X-ray crystallography showed a virtually identical HSP90 binding mode. However, the dissociation constant (K(d)) of VER-50589 was 4.5 +/- 2.2 nmol/L compared with 78.0 +/- 10.4 nmol/L for VER-49009, attributable to higher enthalpy for VER-50589 binding. A competitive binding assay gave a lower IC(50) of 21 +/- 4 nmol/L for VER-50589 compared with 47 +/- 9 nmol/L for VER-49009. Cellular uptake of VER-50589 was 4-fold greater than for VER-49009. Mean cellular antiproliferative GI(50) values for VER-50589 and VER-49009 for a human cancer cell line panel were 78 +/- 15 and 685 +/- 119 nmol/L, respectively, showing a 9-fold potency gain for the isoxazole. Unlike 17-AAG, but as with CCT018159, cellular potency of these analogues was independent of NAD(P)H:quinone oxidoreductase 1/DT-diaphorase and P-glycoprotein expression. Consistent with HSP90 inhibition, VER-50589 and VER-49009 caused induction of HSP72 and HSP27 alongside depletion of client proteins, including C-RAF, B-RAF, and survivin, and the protein arginine methyltransferase PRMT5. Both caused cell cycle arrest and apoptosis. Extent and duration of pharmacodynamic changes in an orthotopic human ovarian carcinoma model confirmed the superiority of VER-50589 over VER-49009. VER-50589 accumulated in HCT116 human colon cancer xenografts at levels above the cellular GI(50) for 24 h, resulting in 30% growth inhibition. The results indicate the therapeutic potential of the resorcinylic pyrazole/isoxazole amide analogues as HSP90 inhibitors..
Raynaud, F.I., Hayes, A., Martins, V., Smith, N.F., Sharp, S.Y., Valenti, M., Henley, A., Matthews, T.P., Cheung, K.M., Kalusa, A., et al.
(2007). Cassette dosing in tumor bearing animals for the discovery of NVP-AUY922, a novel HSP90 inhibitor. Mol cancer ther,
Eccles, S.A., Sharp, S.Y., Raynaud, F.I., Valenti, M., Patterson, L., Gowan, S., Boxall, K., Aherne, W., Rowlands, M., Hayes, A., et al.
(2007). NVP-AUY922, a novel diarylisoxazole resorcinol HSP90 inhibitor, potently inhibits growth and metastasis of human tumor xenografts. Mol cancer ther,
Hilton, S.T. & Jones, K.
(2007). The tandem radical route to indole alkaloids: an unusual rearrangement reaction. Arkivoc,
Francis, N.J., Rowlands, M., Travers, J., Reynissen, J., Hardcastle, A., Stimson, L., Gamblin, S., Jones, K., Workman, P. & Aherne, W., et al.
(2006). A high throughput screen and secondary assays for the identification and evaluation of histone methyltransferase inhibitors. Ejc suppl,
McDonald, E., Jones, K., Brough, P.A., Drysdale, M.J. & Workman, P.
(2006). Discovery and development of pyrazole-scaffold Hsp90 inhibitors. Curr top med chem,
This review explains why the chaperone Hsp90 is an exciting protein target for the discovery of new drugs to treat cancer in the clinic, and summarises the properties of natural product derived inhibitors before relating the discovery and current state of development of synthetic pyrazole compounds. Blockade of Hsp90 results in reduced cellular levels of several proteins implicated in cancer including CDK4, ERBB2 and C-RAF, and causes simultaneous inhibition of cancer cell proliferation in culture and of tumor xenograft growth in vivo. Hsp90 has an ATPase domain that is necessary for its Hsp chaperone function, and X-ray crystallography has shown that natural product inhibitors (geldanamycin, radicicol) of Hsp90 function bind to this domain. High throughput assays focusing on the ATPase activity of Hsp90 were developed and used to discover novel chemical starting points for cancer drug discovery. The discovery, synthesis and SAR of 3,4-diaryl pyrazoles is described. X-Ray crystallography of protein-inhibitor complexes revealed important interactions involving the resorcinol substituent at C-3, and these X-ray structures strongly influenced subsequent medicinal chemistry research that has resulted in highly potent inhibitors with sub-micromolar activity in cells. SAR and X-ray data are summarised for analogues in which the 4-phenyl substituent is replaced by amides or piperazine derivatives. Prospects for the pyrazoles as they progress towards clinical development are discussed in relation to current Phase I trials with derivatives of geldanamycin..
McDonald, E., Workman, P. & Jones, K.
(2006). Inhibitors of the HSP90 molecular chaperone: attacking the master regulator in cancer. Curr top med chem,
The heat shock protein 90 (HSP90) chaperones represent some 1-2% of all cellular protein and are key players in protein quality control in cells. They are over expressed in many human cancers and the fact that many oncogenic proteins are clients has prompted much recent research on HSP90 inhibitors as new cancer therapeutics. A brief introduction is followed by a detailed review of the various classes of inhibitors, both natural product-based and synthetic, that have emerged over the last decade. The natural products geldanamycin, radicicol and novobiocin have provided the start points for new drugs in this area and their medicinal chemistry is reviewed, including the exciting recent results emerging from clinical trials using geldanamycin analogues. The detailed understanding of the binding mode of these compounds to HSP90 has been significantly enhanced by X-ray crystallography of HSP90 constructs co-crystallised with various ligands. Efforts to replace the natural product inhibitors with more drug-like synthetic compounds have mushroomed over the last 4 years. The purines and the 3,4-diarylpyrazoles have proven to be the most successful and their medicinal chemistry is reviewed with particular emphasis on structure-based design. Protein/ligand co-crystal structures have shown that conserved water molecules in the active site are a vital part of the hydrogen-bonding network established on binding both natural product and synthetic inhibitors. Medicinal chemists have used this information to develop high affinity lead compounds. Recent research provides the platform for exciting developments in the area of HSP90 inhibition over the next few years..
Rossiter, S., Peron, J.M., Whitfield, P.J. & Jones, K.
(2005). Synthesis and anthelmintic properties of arylquinolines with activity against drug-resistant nematodes. Bioorg med chem lett,
2,4-Disubstituted quinolines with additional substituents in positions 5-8 have been found to have anthelmintic properties. A number of 2,4-dimethoxy-6- or 8-arylquinolines have potent activity against the sheep nematode Haemonchus contortus, with LD99 values of the same order of magnitude as levamisole. These arylquinolines maintain their activity against levamisole-, ivermectin- and thiabendazole-resistant strains of H. contortus. (c) 2005 Elsevier Ltd. All rights reserved..
Tyrrell, E., Allen, J., Jones, K. & Beauchet, R.
(2005). Asymmetric 1,3-dipolar cycloaddition reactions of nitrones with (S)-(-)-4-benzyl-N-methacryloyl-2-oxazolidinone. Synthesis-stuttgart,
Gravett, E.C., Hilton, P.J., Jones, K. & Peron, J.M.
(2003). A new route to 5-aryl and 5-heteroaryl-2-pyrones via Suzuki coupling of a 2-pyrone-5-boronate ester. Synlett,
Jones, K., Roset, X., Rossiter, S. & Whitfield, P.
(2003). Demethylation of 2,4-dimethoxyquinolines: the synthesis of atanine. Org biomol chem,
The synthesis of the quinoline alkaloid atanine 6, by selective demethylation of the 2,4-dimethoxyquinoline 11 is presented. An alternative demethylation utilising a thiolate anion leads to the regioisomeric 4-hydroxyquinoline 13..
Escolano, C. & Jones, K.
(2002). Aryl radical cyclisation onto pyrroles. Tetrahedron,
Escolano, C., Vallverdu, L. & Jones, K.
(2002). Reaction of indolin-2-ones with cerium(IV) ammonium nitrate. Tetrahedron,
Jones, K. & Toutounji, T.
(2001). A short protocol for the synthesis of spirocyclic tetrahydrofurans via intramolecular O-H insertion. Tetrahedron,
Gravett, E.C., Hilton, P.J., Jones, K. & Romero, F.
(2001). A Suzuki coupling approach to bufadienolides. Tetrahedron letters,
Ong, Q., Hameyer, H., Handa, S. & Jones, K.
(2001). Synthetic studies on morphine-based analgesics: an approach to angular substitution in 4a-aryldecahydroisoquinolines via dienolate chemistry. Tetrahedron letters,
Hilton, S.T., Ho, T.C., Pljevaljcic, G., Schulte, M. & Jones, K.
(2001). A tandem radical approach to the ABCE-rings of the Aspidosperma and Strychnos alkaloids. Chemical communications,
Escolano, C. & Jones, K.
(2000). Aryl radical cyclisation onto pyrroles: a divergent synthesis of spiropyrrolidinyloxindoles and pyrroloquinolines. Tetrahedron letters,
Jones, K., Fiumana, A. & Escudero-Hernandez, M.L.
(2000). Pyridine radicals in synthesis Part 3: Cyclopentannulation of pyridine via the 3-pyridyl radical and a formal synthesis of (+/-)-oxerine. Tetrahedron,
Ashraf, M.A., Jones, K. & Handa, S.
(2000). Biomimetic ligands for transition metals: catechol-containing peptides. Bioorg med chem lett,
The tetrapeptide ligands 6a and 6b containing a catechol moiety have been synthesised and their metal binding with Fe(III), Mn(III) and Cu(II) has been studied using fluorescence spectroscopy..
Hilton, S.T., Ho, T.C., Pljevaljcic, G. & Jones, K.
(2000). A new route to spirooxindoles. Org lett,
[reaction: see text]Reaction of indole amides 5 with tributylstannane gave spiroindolenines 9 which are readily converted into spiropyrrolidinyloxindoles. This tricyclic system is found in a number of interesting natural products..
Fiumana, A. & Jones, K.
(2000). Annulation of indole via indole radicals: addition of the 2-indolyl radical to aromatic rings. Tetrahedron letters,
Jones, K. & Storey, J.M.
(2000). Intramolecular organolithium addition to indol-2(3H)-ones; an approach to the synthesis of pyrrolo[1,2-a]indoles and pyrido[1,2-a]indoles. Journal of the chemical society-perkin transactions 1,
Brunton, S.A. & Jones, K.
(2000). The synthesis of 3-methyleneindol-2(3H)-ones related to mitomycins via 5-exo-dig aryl radical cyclisation. Journal of the chemical society-perkin transactions 1,
Fiumana, A. & Jones, K.
(1999). Intermolecular reactions of indol-2-yl radicals: a new route to 2-substituted indoles. Chemical communications,
Jones, K., Brunton, S.A. & Gosain, R.
(1999). The aryl radical route to oxindoles: dependence on temperature and tin hydride concentration. Tetrahedron letters,
Jones, K., Hibbert, F. & Keenan, M.
(1999). Glowing jellyfish, luminescence and a molecule called coelenterazine. Trends biotechnol,
Luminescence has assumed an important role in analytical biochemistry and molecular biology as an extremely sensitive method for determining the concentration of specific ions and molecules. The luminescent system of the jellyfish Aequorea victoria consists of the photoprotein aequorin, which contains the molecule coelenterazine as a prosthetic group and shows considerable potential in this area..
Jones, K. & Escudero-Hernandez, M.L.
(1998). A short synthesis of (+/-)-actinidine. Tetrahedron,
Dobbs, A.P., Jones, K. & Veal, K.T.
(1998). Heteroaryl radicals in synthesis: Radical cyclisation reactions of 2-bromoindoles. Tetrahedron,
Ho, T.C. & Jones, K.
(1997). A synthesis of the tricyclic pyrroloquinoline core of martinelline. Tetrahedron,
Dobbs, A.P., Jones, K. & Veal, K.T.
(1997). Radical cyclisation reactions of 7-bromoindoles. Tetrahedron letters,
Jones, K., Newton, R.F. & Yarnold, C.J.
(1996). Synthetic studies on the ceveratrum alkaloid skeleton. Tetrahedron,
Houghton, P.J., Osibogun, I.M., Woldemariam, T.Z. & Jones, K.
(1995). Heteronuclear NMR studies of the chromone alkaloids and revision of the structure of some piperidino-chromone alkaloids. Planta med,
The 13C-NMR spectra of seven chromone alkaloids isolated from Schumanniophyton magnificum have been obtained. Assignment of signals was carried out with the help of heteronuclear coupling experiments and other correlation techniques on the alkaloids and their acyl derivatives. On the basis of the signals observed the structures of the piperidino-alkaloid schumannificine and its N-methyl and anhydro analogues have been revised to that of a piperidone ring linked to the noreugenin via a carbon-carbon bond and a lactol bridge..
JONES, K., HO, T.C. & WILKINSON, J.
(1995). ARYL RADICAL CYCLIZATION ON TO A PYRROLE NUCLEUS. Tetrahedron letters,
JONES, K. & STOREY, J.M.
(1993). ARYL RADICAL CYCLIZATION APPROACH TO HIGHLY SUBSTITUTED OXINDOLES RELATED TO MITOMYCINS. Tetrahedron letters,
JONES, K. & STOREY, J.M.
(1993). A ROUTE TO THE PYRROLO[1,2-A]INDOLENINE RING-SYSTEM VIA INTERMOLECULAR ORGANOLITHIUM ADDITION TO AN OXINDOLE. Tetrahedron,
CLARK, A.J. & JONES, K.
(1992). COBALT-MEDIATED ARYL RADICAL CYCLIZATIONS - A FORMAL SYNTHESIS OF PHYSOVENINE. Tetrahedron,
STOREY, J.M., MCCARTHY, C. & JONES, K.
(1991). INTRAMOLECULAR ALKYLLITHIUM ADDITIONS TO LACTAMS - A SYNTHESIS OF 2,3,9,9A-TETRAHYDRO-1H-PYRROLO[1,2-A]INDOLES (PYRROLO[1,2-A]INDOLENINES) RELATED TO MITOMYCINS. Journal of the chemical society-chemical communications,
LOPEZTUDANCA, P.L., JONES, K. & BROWNBRIDGE, P.
(1991). SUBSTITUENT CONTROL IN THE SYNTHESIS OF TETRAHYDROPYRANS, OXEPANES AND OXOCANES BY EPISULPHONIUM ION-MEDIATED CYCLIZATION. Tetrahedron letters,
WOO, K.C. & JONES, K.
(1991). ASYMMETRIC-SYNTHESIS FROM ALPHA-AMINO-ACIDS - SOME REACTIONS OF (S)-PYROGLUTAMATE. Tetrahedron letters,
JONES, K. & WOO, K.C.
(1991). A TOTAL SYNTHESIS OF (-)-RUSPOLINONE. Tetrahedron,
JONES, K. & WOOD, W.W.
(1988). A SYNTHESIS OF (2S,6S)-2-HYDROXYMETHYL-6-METHOXYTETRAHYDROPYRAN - A USEFUL CHIRAL INTERMEDIATE. Journal of the chemical society-perkin transactions 1,
JONES, K. & WOOD, W.W.
(1987). AN APPROACH TO THE TOTAL SYNTHESIS OF THE PRELOG-DJERASSI LACTONE. Journal of the chemical society-perkin transactions 1,
WRIGHT, C., SHULKIND, M., JONES, K. & THOMPSON, M.
(1987). A FORMAL TOTAL SYNTHESIS OF GENESERINE. Tetrahedron letters,
JONES, K. & WOOD, W.W.
(1986). THE PREPARATION AND ATTEMPTED ALKYLATION OF SOME 6-CYANO-CARBOHYDRATES. Carbohydrate research,
HANDA, S., JONES, K. & NEWTON, C.G.
(1986). AN UNUSUAL SOLVENT EFFECT IN AN INTRAMOLECULAR DIELS-ALDER REACTION. Journal of the chemical society-chemical communications,
JONES, K., THOMPSON, M. & WRIGHT, C.
(1986). AN EFFICIENT SYNTHESIS OF SPIRO[CYCLOHEXANE-1,3'-INDOL-2'(3'H)-ONES] VIA RADICAL CYCLIZATION. Journal of the chemical society-chemical communications,
HANDA, S., JONES, K., NEWTON, C.G. & WILLIAMS, D.J.
(1985). A SHORT, STEREOSPECIFIC SYNTHESIS OF A MORPHINE FRAGMENT VIA AN INTRAMOLECULAR DIELS-ALDER REACTION. Journal of the chemical society-chemical communications,
BATTERSBY, A.R., JONES, K. & SNOW, R.J.
(1983). NOVEL METHODS FOR DEMETALATING TETRAPYRROLIC METALLO-MACROCYCLES. Angewandte chemie-international edition,
MONTFORTS, F.P., OFNER, S., RASETTI, V., ESCHENMOSER, A., WOGGON, W.D., JONES, K. & BATTERSBY, A.R.
(1979). SYNTHETIC APPROACH TO THE ISOBACTERIOCHLORIN MACROCYCLE. Angewandte chemie-international edition in english,
BATTERSBY, A.R., JONES, K., MCDONALD, E., ROBINSON, J.A. & MORRIS, H.R.
(1977). STRUCTURES AND CHEMISTRY OF ISOBACTERIOCHLORINS FROM DESULFOVIBRIO-GIGAS. Tetrahedron letters,