Meaningful co-production to bring meaningful change: Developing the Allied Health Professionals Dementia Framework for Wales together

In line with increasing participatory approaches to service and research design, there is a growing appreciation of the need to understand the lived experience of people accessing care and support, including people living with dementia, their carers and supporters. This article describes the process and value of co-production, used alongside principles of appreciative inquiry and evidence-informed practice, as an approach to developing a strategic workforce framework, aimed at increasing access to Allied Health Professionals (AHPs) for people living with dementia and their carers. Engaging in the co-production approach throughout the project lifecycle resulted in positive outcomes as reported by people with lived experience and professionals who were involved, as well as a published national framework that is rooted in the first-hand experiences of people living with dementia, their carers and supporters.

Fragment-Based Discovery of Allosteric Inhibitors of SH2 Domain-Containing Protein Tyrosine Phosphatase-2 (SHP2)

The ubiquitously expressed protein tyrosine phosphatase SHP2 is required for signaling downstream of receptor tyrosine kinases (RTKs) and plays a role in regulating many cellular processes. Genetic knockdown and pharmacological inhibition of SHP2 suppresses RAS/MAPK signaling and inhibit the proliferation of RTK-driven cancer cell lines. Here, we describe the first reported fragment-to-lead campaign against SHP2, where X-ray crystallography and biophysical techniques were used to identify fragments binding to multiple sites on SHP2. Structure-guided optimization, including several computational methods, led to the discovery of two structurally distinct series of SHP2 inhibitors binding to the previously reported allosteric tunnel binding site (Tunnel Site). One of these series was advanced to a low-nanomolar lead that inhibited tumor growth when dosed orally to mice bearing HCC827 xenografts. Furthermore, a third series of SHP2 inhibitors was discovered binding to a previously unreported site, lying at the interface of the C-terminal SH2 and catalytic domains.

Abstract 3722: Exploring the role of eIF4E in cancer cells with targeted protein degradation

Initiation of translation is considered the main rate-limiting step of protein synthesis and requires the recognition of 5’ m7G-cap on mature mRNAs and the formation of eukaryotic translation initiation factor 4F (eIF4F) multi-protein mRNA cap-binding complex. Formation of this complex requires the interaction of eIF4E and the scaffold protein eIF4G, and RNA helicase eIF4A. This eIF4F complex along with eIF3 mediate the recruitment of the 40S ribosomal particle to the 5′ cap of mRNA. Activation of eIF4E is a regulatory hub of many major oncogenic pathways, thus, targeting eIF4E has emerged as a potential therapeutic strategy in cancer.

Here we have used a targeted protein degradation approach coupled with genetic rescue to explore the molecular and cellular dependency of cancer cells on eIF4E. Stable H1299 human NSCLC clones expressing FKBP12F36V-tagged eIF4E but lacking endogenous eIF4E were established. Treatment of multiple N- or C-tagged-eIF4E clones with dTAGv-1, an FKBP12F36V selective heterobifunctional molecule that recruits VHL, induced rapid degradation of eIF4E to undetectable levels by 6hr exposure. This also resulted in reduced expression of MCL1, a previously reported biomarker of eIF4E activity. Longer exposures to dTAGv-1 resulted in a cytostasis that was not associated with cell death. A diastereomer negative control of dTAGv-1 that cannot recruit VHL did not elicit loss of eIF4E or the downstream events associated with its loss. Global analysis of protein synthesis initiation by RIBOseq and proteome profiling following dTAGv-1 treatment out to 32hr exposure demonstrated surprisingly few alterations in protein expression despite the significant effect on cancer cell growth.

We also expressed wild-type or eIF4E mutants predicted to disrupt key functions and determined their ability to rescue molecular or cellular phenotype associate with eIF4E-loss following dTAGv-1 treatment. Expression of wild-type eIF4E completely rescued cell growth and MCL1 expression. A W56A mutant predicted to disrupt mRNA-cap binding was unable to rescue eIF4E loss. In contrast, expression of W73F or S290A mutants (predicted to disrupt eIF4G binding or exhibit reduced eIF4E activity, respectively) were able to rescue the loss of eIF4E.

In summary, our rescue experiments show that mRNA-cap binding by eIF4E is required and that eIF4E:eIF4G interaction in cells may be more complex than predicted. This may also explain the challenges associated with developing selective and cellularly potent inhibitors of the eIF4E:eIF4G interaction and that targeting mRNA-cap binding may be a more effective strategy. We predicted that removing eIF4E would impact on the global synthesis of many proteins. However, our data demonstrate that targeting eIF4E leads to limited effects on protein synthesis that remain sufficient to inhibit cancer cell growth. Further experiments are underway to understand which proteins drive this dependency on eIF4E.

Citation Format: Swee Y. Sharp, Marianna Martella, Christopher I. Milton, George Ward, Caroline Richardson, Andrew Woodhead, Paul A. Clarke. Exploring the role of eIF4E in cancer cells with targeted protein degradation. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3722.

Fragment-to-Lead Medicinal Chemistry Publications in 2021

This Perspective is the seventh in an annual series that summarizes successful Fragment-to-Lead (F2L) case studies published in a given year. A tabulated summary of relevant articles published in 2021 is provided, and features such as target class, screening methods, and ligand efficiency are discussed, both for the 2021 examples and for the combined examples over the years 2015-2021. In addition, trends and new developments in the field are summarized. In particular, the use of structural information in fragment-based drug discovery is discussed.

Injury incidence and locomotor behaviours in polocrosse ponies

There is currently limited information available regarding the physical demands of polocrosse and no information on the specific veterinary problems faced by polocrosse ponies in the United Kingdom. Polocrosse requires the ponies that compete to perform rapid acceleration, sharp turns and sudden halts. The study aim was to explore the injury incidence and type of injury, between the three positions played by polocrosse ponies. Injuries that resulted in withdrawal of a pony during outdoor tournaments in the UK over the 2015 and 2016 seasons were recorded. In addition, GPS data and locomotor behaviours were recorded during winter league tournaments in 2017 and compared between the different position ponies. Ponies that played in the defence position were significantly more likely to become injured (P<0.001) with lameness being the most common cause for withdrawal (P<0.001). Ponies playing in the attack position achieved the fastest speeds and covered the furthest distance. Defence ponies performed significantly more abrupt halts (P=0.007), walk to gallop transitions (P=0.017) and sudden changes in direction (P=0.01) than midfield ponies and more of each manoeuvre than attack ponies, although this was not significant. It is important that the physical demands placed upon polocrosse ponies are investigated further; this will allow identification of injury risk factors, inform training programmes and improve the performance and welfare of the horses involved.

Masseter muscle rigidity and the role of DNA analysis to confirm malignant hyperthermia susceptibility

Malignant hyperthermia (MH) is an uncommon, autosomal dominant disorder of skeletal muscle, triggered by inhalational anaesthetics or depolarizing muscle relaxants. Masseter muscle rigidity (MMR) can be regarded as potentially a preceding sign for an MH reaction. Susceptibility to MH can be determined by the in vitro contracture test (IVCT) or DNA analysis where a familial variant is known. Our aims were to review patients with MMR, where IVCT and DNA analysis had been undertaken, to determine if DNA analysis could be used as an initial screening tool for MH susceptibility, and, by reviewing standard monitored variables (SMVs), to determine if any clinical characteristics could be used to differentiate between MMR patients who are MH susceptible (MHS) and those who are not. Patients with MMR were identified from the Palmerston North Hospital MH Reactions Database. IVCT and DNA analysis results were documented. DNA testing was performed retrospectively in the majority of patients as many patients had presented before DNA analysis was available. Forty-one patients were analysed. Fourteen were DNA positive/IVCT positive and six DNA positive only (48% in total), seven were IVCT positive/DNA negative and 14 were IVCT normal. Increased creatine kinase (>18,000 units/L) was consistent with MH susceptibility. Severity of MMR was not linked to MH susceptibility. This study confirmed that DNA analysis can be used as a first-line test for MH susceptibility in patients presenting with MMR (consistent with European MH Group recommendations). Creatine kinase was the only SMV that was significantly different between MHS and MH normal individuals.

A comparison between the nutritive value of short-cutting cycle, high temperature-dried alfalfa and timothy hay for horses

The objective was to evaluate the nutritive value of short-cutting cycle, high temperature-dried (SCCHTD) alfalfa compared to timothy hay. This was achieved by carrying out 4 x 4 Latin Square digestibility trial using 4 Thoroughbred (one three-quarter Thoroughbred) horses (mean liveweight, 531 kg). The four dietary treatments were 0AA (timothy hay only), 33AA (0.33 alfalfa: 0.67 timothy hay), 67AA (0.67 alfalfa: 0.33 timothy hay) and 100AA (alfalfa only). Digestibility data were obtained by using acid-insoluble ash to estimate apparent digestibility coefficients of nutrients. Rate of passage of the feedstuff was determined using chromium-mordanted hay. Plasma triglyceride and cholesterol concentrations were estimated. The digestibilities of organic matter (0.63), energy (0.57) and crude protein (0.74) of the alfalfa were significantly (P less than 0.001) higher than those for the hay (0.45, 0.43 and 0.36 respectively). The fibre components of alfalfa and hay were digested to the same extent but the ether extract of alfalfa was less well digested. Alfalfa saponins had no consistently significant effects on plasma cholesterol and triglyceride values but may contribute to the negative digestibility of alfalfa ether extract. We conclude that SCCHTD alfalfa is of much higher nutritive value than timothy hay when fed to Thoroughbred horses.

Potential of alfalfa as a source of calcium for calcium deficient horses

The potential of short-cutting cycle, high temperature-dried alfalfa as a source of calcium for horses was determined by means of a 4 x 4 Latin square digestibility trial using four thoroughbred horses (mean liveweight 531 kg). The four dietary treatments were timothy hay alone, 33 per cent alfalfa and 67 per cent timothy hay, 67 per cent alfalfa and 33 per cent timothy hay, and alfalfa alone. Significantly more calcium and magnesium were absorbed from the alfalfa than from the hay. Phosphorus absorption appeared to be unaffected by treatment. Alfalfa calcium was more available than timothy hay calcium (apparent absorption coefficients of 0.78 and 0.15, respectively) and there was less variation between individual horses in their ability to absorb calcium from alfalfa. Horses fed alfalfa had significantly higher creatinine clearance ratios for calcium (P less than 0.01) and magnesium (P less than 0.001) than horses fed hay, but the creatinine clearance ratio for phosphorus was lower in horses fed hay alone.