Structure-based discovery of potent WD repeat domain 5 inhibitors that demonstrate efficacy and safety in preclinical animal models.

WD repeat domain 5 (WDR5) is a core scaffolding component of many multiprotein complexes that perform a variety of critical chromatin-centric processes in the nucleus. WDR5 is a component of the mixed lineage leukemia MLL/SET complex and localizes MYC to chromatin at tumor-critical target genes. As a part of these complexes, WDR5 plays a role in sustaining oncogenesis in a variety of human cancers that are often associated with poor prognoses. Thus, WDR5 has been recognized as an attractive therapeutic target for treating both solid and hematological tumors. Previously, small-molecule inhibitors of the WDR5-interaction (WIN) site and WDR5 degraders have demonstrated robust in vitro cellular efficacy in cancer cell lines and established the therapeutic potential of WDR5. However, these agents have not demonstrated significant in vivo efficacy at pharmacologically relevant doses by oral administration in animal disease models. We have discovered WDR5 WIN-site inhibitors that feature bicyclic heteroaryl P7 units through structure-based design and address the limitations of our previous series of small-molecule inhibitors. Importantly, our lead compounds exhibit enhanced on-target potency, excellent oral pharmacokinetic (PK) profiles, and potent dose-dependent in vivo efficacy in a mouse MV4:11 subcutaneous xenograft model by oral dosing. Furthermore, these in vivo probes show excellent tolerability under a repeated high-dose regimen in rodents to demonstrate the safety of the WDR5 WIN-site inhibition mechanism. Collectively, our results provide strong support for WDR5 WIN-site inhibitors to be utilized as potential anticancer therapeutics.

Interaction with WDR5 promotes target gene recognition and tumorigenesis by MYC.

MYC is an oncoprotein transcription factor that is overexpressed in the majority of malignancies. The oncogenic potential of MYC stems from its ability to bind regulatory sequences in thousands of target genes, which depends on interaction of MYC with its obligate partner, MAX. Here, we show that broad association of MYC with chromatin also depends on interaction with the WD40-repeat protein WDR5. MYC binds WDR5 via an evolutionarily conserved "MYC box IIIb" motif that engages a shallow, hydrophobic cleft on the surface of WDR5. Structure-guided mutations in MYC that disrupt interaction with WDR5 attenuate binding of MYC at ∼80% of its chromosomal locations and disable its ability to promote induced pluripotent stem cell formation and drive tumorigenesis. Our data reveal WDR5 as a key determinant for MYC recruitment to chromatin and uncover a tractable target for the discovery of anticancer therapies against MYC-driven tumors.

WDR5 is a conserved regulator of protein synthesis gene expression.

WDR5 is a highly-conserved nuclear protein that performs multiple scaffolding functions in the context of chromatin. WDR5 is also a promising target for pharmacological inhibition in cancer, with small molecule inhibitors of an arginine-binding pocket of WDR5 (the 'WIN' site) showing efficacy against a range of cancer cell lines in vitro. Efforts to understand WDR5, or establish the mechanism of action of WIN site inhibitors, however, are stymied by its many functions in the nucleus, and a lack of knowledge of the conserved gene networks-if any-that are under its control. Here, we have performed comparative genomic analyses to identify the conserved sites of WDR5 binding to chromatin, and the conserved genes regulated by WDR5, across a diverse panel of cancer cell lines. We show that a specific cohort of protein synthesis genes (PSGs) are invariantly bound by WDR5, demonstrate that the WIN site anchors WDR5 to chromatin at these sites, and establish that PSGs are bona fide, acute, and persistent targets of WIN site blockade. Together, these data reveal that WDR5 plays a predominant transcriptional role in biomass accumulation and provide further evidence that WIN site inhibitors act to repress gene networks linked to protein synthesis homeostasis.

Implementing supportive exercise interventions in the colorectal cancer care pathway: a process evaluation of the PREPARE-ABC randomised controlled trial.

BACKGROUND: A colorectal resection is standard treatment for patients with colorectal cancer (CRC). However, the procedure results in significant post-operative mortality and reduced quality of life. Maximising pre-operative cardiopulmonary fitness could improve post-surgical outcomes. PREPARE-ABC is a multi-centre, three-armed, randomised controlled trial investigating the effects of exercise interventions, with motivational support on short and longer-term recovery outcomes in CRC patients undergoing major lower-gastrointestinal surgery. The trial included an internal pilot phase with parallel process evaluation. The aim of the process evaluation was to optimise intervention implementation for the main trial. METHODS: Mixed methods process evaluation conducted in 14 UK hospitals between November 2016 and March 2018. Data included a site profile questionnaire and telephone scoping interview with hospital staff, 34 qualitative observations of standard care and 14 observations of intervention delivery, 13 semi-structured interviews with healthcare professionals (HCPs) and 28 semi-structured interviews with patients. Data analysis focused on describing intervention delivery within each arm, assessing fidelity, acceptability and how variation in delivery was linked to contextual characteristics. RESULTS: Standard care exercise advice was typically limited to maintaining current activity levels, and with lead-in time to surgery affecting whether any exercise advice was provided. Variation in HCP capacity affected the ability of colorectal units to deploy staff to deliver the intervention. Patients' exercise history and motivation prior to surgery influenced HCP perceptions and delivery of the motivational components. Observations indicated a high level of fidelity to delivery of the exercise interventions. All but one of the 28 interviewed patients reported increasing exercise levels as a result of receiving the intervention, with most finding them motivational and greatly valuing the enhanced level of social support (versus standard care) provided by staff. CONCLUSION: Hospital-supervised and home-based exercise interventions were highly acceptable for most patients undergoing surgery for CRC. Delivery of pre- and post-operative exercise within the CRC care pathway is feasible but systematic planning of capacity and resources is required to optimise implementation.

AtPIG-S, a predicted Glycosylphosphatidylinositol Transamidase subunit, is critical for pollen tube growth in Arabidopsis.

BACKGROUND: Glycosylphosphatidylinositol (GPI) addition is one of the several post-translational modifications to proteins that increase their affinity for membranes. In eukaryotes, the GPI transamidase complex (GPI-T) catalyzes the attachment of pre-assembled GPI anchors to GPI-anchored proteins (GAPs) through a transamidation reaction. A mutation in AtGPI8 (gpi8-2), the putative catalytic subunit of GPI-T in Arabidopsis, is transmitted normally through the female gametophyte (FG), indicating the FG tolerates loss of GPI transamidation. In contrast, gpi8-2 almost completely abolishes male gametophyte (MG) function. Still, the unexpected finding that gpi8-2 FGs function normally requires further investigation. Additionally, specific developmental defects in the MG caused by loss of GPI transamidation remain poorly characterized. RESULTS: Here we investigated the effect of loss of AtPIG-S, another GPI-T subunit, in both gametophytes. Like gpi8-2, we showed that a mutation in AtPIG-S (pigs-1) disrupted synergid localization of LORELEI (LRE), a putative GAP critical for pollen tube reception by the FG. Still, pigs-1 is transmitted normally through the FG. Conversely, pigs-1 severely impaired male gametophyte (MG) function during pollen tube emergence and growth in the pistil. A pPIGS:GFP-PIGS transgene complemented these MG defects and enabled generation of pigs-1/pigs-1 seedlings. However, the pPIGS:GFP-PIGS transgene seemingly failed to rescue the function of AtPIG-S in the sporophyte, as pigs-1/pigs-1, pPIGS:GFP-PIGS seedlings died soon after germination. CONCLUSIONS: Characterization of pigs-1 provided further evidence that the FG tolerates loss of GPI transamidation more than the MG and that the MG compared to the FG may be a better haploid system to study the role of GPI-anchoring. Pigs-1 pollen develops normally and thus represent a tool in which GPI anchor biosynthesis and transamidation of GAPs have been uncoupled, offering a potential way to study free GPI in plant development. While previously reported male fertility defects of GPI biosynthesis mutants could have been due either to loss of GPI or GAPs lacking the GPI anchor, our results clarified that the loss of mature GAPs underlie male fertility defects of GPI-deficient pollen grains, as pigs-1 is defective only in the downstream transamidation step.

Study protocol: ASCRIBED: the impact of Acute SystematiC inflammation upon cerebRospinal fluId and blood BiomarkErs of brain inflammation and injury in dementia: a study in acute hip fracture patients.

BACKGROUND: Hip fracture represents a substantial acute inflammatory trauma, which may constitute a significant insult to the degenerating brain. Research suggests that an injury of this kind can affect memory and thinking in the future but it is unclear whether, and how, inflammatory trauma injures the brain. The impact of Acute SystematiC inflammation upon cerebRospinal fluId and blood BiomarkErs of brain inflammation and injury in Dementia: a study in acute hip fracture patients (ASCRIBED) explores this relationship, to understand the effect of inflammation on the progression of dementia. METHODS: This protocol describes a multi-centre sample collection observational study. The study utilises the unique opportunity provided by hip fracture operations undertaken via spinal anaesthesia to collect cerebrospinal fluid (CSF) and blood, to investigate the impact of acute brain inflammation caused by hip fracture on the exacerbation of dementia. We will recruit 200 hip fracture patients with a diagnosis or evidence of dementia; and 200 hip fracture patients without dementia. We will also recruit 'Suitable informants', individuals in regular contact with the patient, to provide further proxy evidence of a patient's potential cognitive decline. We will compare these 400 samples with existing CSF and blood samples from a cohort of dementia patients who had not experienced a systemic inflammatory response due to injury. This will provide a comparison between patients with and without dementia who are suffering a systemic inflammatory response; with stable patients living with dementia. DISCUSSION: We will test the hypothesis that hip fracture patients living with dementia show elevated markers of brain inflammation, as well as neuronal injury and Alzheimer-related plaque pathology, in comparison to (1) stable patients living with dementia and (2) hip fracture patients without dementia, as measured by biomarkers in CSF and blood. The findings will address the hypothesis that systemic inflammatory events can exacerbate underlying dementia and inform the search for new treatments targeting inflammation in dementia. TRIAL REGISTRATION: ISRCTN43803769 . Registered 11 May 2017.

Biologically Inspired Design of Nanoparticle Artificial Antigen-Presenting Cells for Immunomodulation.

Particles engineered to engage and interact with cell surface ligands and to modulate cells can be harnessed to explore basic biological questions as well as to devise cellular therapies. Biology has inspired the design of these particles, such as artificial antigen-presenting cells (aAPCs) for use in immunotherapy. While much has been learned about mimicking antigen presenting cell biology, as we decrease the size of aAPCs to the nanometer scale, we need to extend biomimetic design to include considerations of T cell biology-including T-cell receptor (TCR) organization. Here we describe the first quantitative analysis of particle size effect on aAPCs with both Signals 1 and 2 based on T cell biology. We show that aAPCs, larger than 300 nm, activate T cells more efficiently than smaller aAPCs, 50 nm. The 50 nm aAPCs require saturating doses or require artificial magnetic clustering to activate T cells. Increasing ligand density alone on the 50 nm aAPCs did not increase their ability to stimulate CD8+ T cells, confirming the size-dependent phenomenon. These data support the need for multireceptor ligation and activation of T-cell receptor (TCR) nanoclusters of similar sizes to 300 nm aAPCs. Quantitative analysis and modeling of a nanoparticle system provides insight into engineering constraints of aAPCs for T cell immunotherapy applications and offers a case study for other cell-modulating particles.

The ubiquitin-selective chaperone Cdc48/p97 associates with Ubx3 to modulate monoubiquitylation of histone H2B.

Cdc48/p97 is an evolutionary conserved ubiquitin-dependent chaperone involved in a broad array of cellular functions due to its ability to associate with multiple cofactors. Aside from its role in removing RNA polymerase II from chromatin after DNA damage, little is known about how this AAA-ATPase is involved in the transcriptional process. Here, we show that yeast Cdc48 is recruited to chromatin in a transcription-coupled manner and modulates gene expression. Cdc48, together with its cofactor Ubx3 controls monoubiquitylation of histone H2B, a conserved modification regulating nucleosome dynamics and chromatin organization. Mechanistically, Cdc48 facilitates the recruitment of Lge1, a cofactor of the H2B ubiquitin ligase Bre1. The function of Cdc48 in controlling H2B ubiquitylation appears conserved in human cells because disease-related mutations or chemical inhibition of p97 function affected the amount of ubiquitylated H2B in muscle cells. Together, these results suggest a prominent role of Cdc48/p97 in the coordination of chromatin remodeling with gene transcription to define cellular differentiation processes.

Ribosome subunit attrition and activation of the p53-MDM4 axis dominate the response of MLL-rearranged cancer cells to WDR5 WIN site inhibition.

The chromatin-associated protein WD Repeat Domain 5 (WDR5) is a promising target for cancer drug discovery, with most efforts blocking an arginine-binding cavity on the protein called the 'WIN' site that tethers WDR5 to chromatin. WIN site inhibitors (WINi) are active against multiple cancer cell types in vitro, the most notable of which are those derived from MLL-rearranged (MLLr) leukemias. Peptidomimetic WINi were originally proposed to inhibit MLLr cells via dysregulation of genes connected to hematopoietic stem cell expansion. Our discovery and interrogation of small-molecule WINi, however, revealed that they act in MLLr cell lines to suppress ribosome protein gene (RPG) transcription, induce nucleolar stress, and activate p53. Because there is no precedent for an anticancer strategy that specifically targets RPG expression, we took an integrated multi-omics approach to further interrogate the mechanism of action of WINi in human MLLr cancer cells. We show that WINi induce depletion of the stock of ribosomes, accompanied by a broad yet modest translational choke and changes in alternative mRNA splicing that inactivate the p53 antagonist MDM4. We also show that WINi are synergistic with agents including venetoclax and BET-bromodomain inhibitors. Together, these studies reinforce the concept that WINi are a novel type of ribosome-directed anticancer therapy and provide a resource to support their clinical implementation in MLLr leukemias and other malignancies.

Ribosome subunit attrition and activation of the p53-MDM4 axis dominate the response of MLL-rearranged cancer cells to WDR5 WIN site inhibition.

The chromatin-associated protein WD Repeat Domain 5 (WDR5) is a promising target for cancer drug discovery, with most efforts blocking an arginine-binding cavity on the protein called the "WIN" site that tethers WDR5 to chromatin. WIN site inhibitors (WINi) are active against multiple cancer cell types in vitro, the most notable of which are those derived from MLL-rearranged (MLLr) leukemias. Peptidomimetic WINi were originally proposed to inhibit MLLr cells via dysregulation of genes connected to hematopoietic stem cell expansion. Our discovery and interrogation of small molecule WIN site inhibitors, however, revealed that they act in MLLr cell lines to suppress ribosome protein gene (RPG) transcription, induce nucleolar stress, and activate p53. Because there is no precedent for an anti-cancer strategy that specifically targets RPG expression, we took an integrated multi-omics approach to further interrogate the mechanism of action of WINi in MLLr cancer cells. We show that WINi induce depletion of the stock of ribosomes, accompanied by a broad yet modest translational choke and changes in alternative mRNA splicing that inactivate the p53 antagonist MDM4. We also show that WINi are synergistic with agents including venetoclax and BET-bromodomain inhibitors. Together, these studies reinforce the concept that WINi are a novel type of ribosome-directed anti-cancer therapy and provide a resource to support their clinical implementation in MLLr leukemias and other malignancies.

A platelet-mimetic paradigm for metastasis-targeted nanomedicine platforms.

There is compelling evidence that, beyond their traditional role in hemostasis and thrombosis, platelets play a significant role in mediating hematologic mechanisms of tumor metastasis by directly and indirectly interacting with pro-metastatic cancer cells. With this rationale, we hypothesized that platelets can be an effective paradigm to develop nanomedicine platforms that utilize platelet-mimetic interaction mechanisms for targeted diagnosis and therapy of metastatic cancer cells. Here we report on our investigation of the development of nanoconstructs that interact with metastatic cancer cells via platelet-mimetic heteromultivalent ligand-receptor pathways. For our studies, pro-metastatic human breast cancer cell line MDA-MB-231 was studied for its surface expression of platelet-interactive receptors, in comparison to another low-metastatic human breast cancer cell line, MCF-7. Certain platelet-interactive receptors were found to be significantly overexpressed on the MDA-MB-231 cells, and these cells showed significantly enhanced binding interactions with active platelets compared to MCF-7 cells. Based upon these observations, two specific receptor interactions were selected, and corresponding ligands were engineered onto the surface of liposomes as model nanoconstructs, to enable platelet-mimetic binding to the cancer cells. Our model platelet-mimetic liposomal constructs showed enhanced targeting and attachment of MDA-MB-231 cells compared to the MCF-7 cells. These results demonstrate the promise of utilizing platelet-mimetic constructs in modifying nanovehicle constructs for metastasis-targeted drug as well as modifying surfaces for ex-vivo cell enrichment diagnostic technologies.

BabyBreathe trial: protocol for a randomised controlled trial of a complex intervention to prevent postpartum return to smoking.

INTRODUCTION: Many people quit smoking during pregnancy, but postpartum smoking relapse is common. Maintaining smoking abstinence achieved during pregnancy is key to improving maternal and child health. There are no evidence-based interventions for preventing postpartum smoking relapse. This trial aims to determine whether an intervention to prevent postpartum relapse is effective and cost-effective. METHODS AND ANALYSIS: A randomised controlled trial of a complex intervention to prevent postpartum smoking relapse (BabyBreathe), with internal pilot, economic and process evaluations. Participants are adults who are pregnant and who report having quit smoking in the 12 months before, or during pregnancy. Participants are eligible if they read and understand English, and provide informed consent. Following consent and biochemical validation of smoking abstinence, participants are randomised to intervention or usual care/control (no specific relapse prevention support). The BabyBreathe intervention consists of manualised advice from a trained member of the health visiting service, health information leaflets for participants and partners, access to the BabyBreathe website and app. At the time of birth, participants are posted the BabyBreathe box and support is provided by text message for up to 12 months postpartum. Target sample size is 880, recruiting across midwifery services at four hubs in England and Scotland and through remote advertising in England, Scotland, Wales and Northern Ireland. Outcomes are collected at 6 and 12 months. The primary outcome is self-reported sustained smoking abstinence at 12 months, carbon monoxide verified. Secondary outcomes include self-reported abstinence, time to relapse, partner smoking status and quality of life. ETHICS AND DISSEMINATION: The trial was approved by the North West Preston Research Ethics committee (21/NW/0017). Dissemination will include publication in peer-reviewed journals, presentation at academic and public conferences including patient and public involvement and to policymakers and practitioners. TRIAL REGISTRATION NUMBER: ISRCTN70307341.

Screening for lipid nanoparticles that modulate the immune activity of helper T cells towards enhanced antitumour activity.

Lipid nanoparticles (LNPs) can be designed to potentiate cancer immunotherapy by promoting their uptake by antigen-presenting cells, stimulating the maturation of these cells and modulating the activity of adjuvants. Here we report an LNP-screening method for the optimization of the type of helper lipid and of lipid-component ratios to enhance the delivery of tumour-antigen-encoding mRNA to dendritic cells and their immune-activation profile towards enhanced antitumour activity. The method involves screening for LNPs that enhance the maturation of bone-marrow-derived dendritic cells and antigen presentation in vitro, followed by assessing immune activation and tumour-growth suppression in a mouse model of melanoma after subcutaneous or intramuscular delivery of the LNPs. We found that the most potent antitumour activity, especially when combined with immune checkpoint inhibitors, resulted from a coordinated attack by T cells and NK cells, triggered by LNPs that elicited strong immune activity in both type-1 and type-2 T helper cells. Our findings highlight the importance of optimizing the LNP composition of mRNA-based cancer vaccines to tailor antigen-specific immune-activation profiles.

A Study of Shrinkage Stress Reduction and Mechanical Properties of Nanogel-Modified Resin Systems.

A series of nanogel compositions were prepared from urethane dimethacrylate (UDMA) and isobornyl methacrylate (IBMA) in the presence of a thiol chain transfer agent. The linear oligomer of IBMA was synthesized by a similar solution polymerization technique. The nanogels were prepared with different crosslinker concentrations to achieve varied branching densities and molecular weights. The prepolymers were dispersed in triethylene glycol dimethacrylate at loading levels ranging from 10 wt% to 50 wt%. Photopolymerization reaction kinetics of all prepolymer modified systems were enhanced relative to the nanogel-free control during early stage polymerization while limiting conversion was similar for most samples. Volumetric polymerization shrinkage was reduced proportionally with the prepolymer content while the corresponding decrease in polymerization stress was potentially greater than an additive linear behavior. Flexural strength for inert linear polymer-modified systems decreased significantly with the increase in the prepolymer content; however, with an increase in the crosslinker concentration within the nanogel additives, and an increase in the concentration of residual pendant reactive sites, flexural strength was maintained or improved regardless of the nanogel loading level. This demonstrates that covalent attachment rather than just physical entanglement with the polymer matrix is important for effective polymer mechanical reinforcement by nanogel additives. Reactive nanogel additives can be considered as a practical, generic means to achieve substantial reductions in polymerization shrinkage and shrinkage stress in common polymers.

WIN site inhibition disrupts a subset of WDR5 function.

WDR5 nucleates the assembly of histone-modifying complexes and acts outside this context in a range of chromatin-centric processes. WDR5 is also a prominent target for pharmacological inhibition in cancer. Small-molecule degraders of WDR5 have been described, but most drug discovery efforts center on blocking the WIN site of WDR5, an arginine binding cavity that engages MLL/SET enzymes that deposit histone H3 lysine 4 methylation (H3K4me). Therapeutic application of WIN site inhibitors is complicated by the disparate functions of WDR5, but is generally guided by two assumptions-that WIN site inhibitors disable all functions of WDR5, and that changes in H3K4me drive the transcriptional response of cancer cells to WIN site blockade. Here, we test these assumptions by comparing the impact of WIN site inhibition versus WDR5 degradation on H3K4me and transcriptional processes. We show that WIN site inhibition disables only a specific subset of WDR5 activity, and that H3K4me changes induced by WDR5 depletion do not explain accompanying transcriptional responses. These data recast WIN site inhibitors as selective loss-of-function agents, contradict H3K4me as a relevant mechanism of action for WDR5 inhibitors, and indicate distinct clinical applications of WIN site inhibitors and WDR5 degraders.

Sustained IGF-1 delivery ameliorates effects of chronic denervation and improves functional recovery after peripheral nerve injury and repair.

Functional recovery following peripheral nerve injury is limited by progressive atrophy of denervated muscle and Schwann cells (SCs) that occurs during the long regenerative period prior to end-organ reinnervation. Insulin-like growth factor 1 (IGF-1) is a potent mitogen with well-described trophic and anti-apoptotic effects on neurons, myocytes, and SCs. Achieving sustained, targeted delivery of small protein therapeutics remains a challenge. We hypothesized that a novel nanoparticle (NP) delivery system can provide controlled release of bioactive IGF-1 targeted to denervated muscle and nerve tissue to achieve improved motor recovery through amelioration of denervation-induced muscle atrophy and SC senescence and enhanced axonal regeneration. Biodegradable NPs with encapsulated IGF-1/dextran sulfate polyelectrolyte complexes were formulated using a flash nanoprecipitation method to preserve IGF-1 bioactivity and maximize encapsulation efficiencies. Under optimized conditions, uniform PEG-b-PCL NPs were generated with an encapsulation efficiency of 88.4%, loading level of 14.2%, and a near-zero-order release of bioactive IGF-1 for more than 20 days in vitro. The effects of locally delivered IGF-1 NPs on denervated muscle and SCs were assessed in a rat median nerve transection-without- repair model. The effects of IGF-1 NPs on axonal regeneration, muscle atrophy, reinnervation, and recovery of motor function were assessed in a model in which chronic denervation is induced prior to nerve repair. IGF-1 NP treatment resulted in significantly greater recovery of forepaw grip strength, decreased denervation-induced muscle atrophy, decreased SC senescence, and improved neuromuscular reinnervation.

Synergistic action of WDR5 and HDM2 inhibitors in SMARCB1-deficient cancer cells.

Rhabdoid tumors (RT) are rare and deadly pediatric cancers driven by loss of SMARCB1, which encodes the SNF5 component of the SWI/SNF chromatin remodeler. Loss of SMARCB1 is associated with a complex set of phenotypic changes including vulnerability to inhibitors of protein synthesis and of the p53 ubiquitin-ligase HDM2. Recently, we discovered small molecule inhibitors of the 'WIN' site of WDR5, which in MLL-rearranged leukemia cells decrease the expression of a set of genes linked to protein synthesis, inducing a translational choke and causing p53-dependent inhibition of proliferation. Here, we characterize how WIN site inhibitors act in RT cells. As in leukemia cells, WIN site inhibition in RT cells causes the comprehensive displacement of WDR5 from chromatin, resulting in a decrease in protein synthesis gene expression. Unlike leukemia cells, however, the growth response of RT cells to WIN site blockade is independent of p53. Exploiting this observation, we demonstrate that WIN site inhibitor synergizes with an HDM2 antagonist to induce p53 and block RT cell proliferation in vitro. These data reveal a p53-independent action of WIN site inhibitors and forecast that future strategies to treat RT could be based on dual WDR5/HDM2 inhibition.

Immunopotentiation by Lymph-Node Targeting of a Malaria Transmission-Blocking Nanovaccine.

A successful malaria transmission blocking vaccine (TBV) requires the induction of a high antibody titer that leads to abrogation of parasite traversal of the mosquito midgut following ingestion of an infectious bloodmeal, thereby blocking the cascade of secondary human infections. Previously, we developed an optimized construct UF6b that elicits an antigen-specific antibody response to a neutralizing epitope of Anopheline alanyl aminopeptidase N (AnAPN1), an evolutionarily conserved pan-malaria mosquito midgut-based TBV target, as well as established a size-controlled lymph node targeting biodegradable nanoparticle delivery system that leads to efficient and durable antigen-specific antibody responses using the model antigen ovalbumin. Herein, we demonstrate that co-delivery of UF6b with the adjuvant CpG oligodeoxynucleotide immunostimulatory sequence (ODN ISS) 1018 using this biodegradable nanoparticle vaccine delivery system generates an AnAPN1-specific immune response that blocks parasite transmission in a standard membrane feeding assay. Importantly, this platform allows for antigen dose-sparing, wherein lower antigen payloads elicit higher-quality antibodies, therefore less antigen-specific IgG is needed for potent transmission-reducing activity. By targeting lymph nodes directly, the resulting immunopotentiation of AnAPN1 suggests that the de facto assumption that high antibody titers are needed for a TBV to be successful needs to be re-examined. This nanovaccine formulation is stable at -20°C storage for at least 3 months, an important consideration for vaccine transport and distribution in regions with poor healthcare infrastructure. Together, these data support further development of this nanovaccine platform for malaria TBVs.

MYC regulates ribosome biogenesis and mitochondrial gene expression programs through its interaction with host cell factor-1.

The oncoprotein transcription factor MYC is a major driver of malignancy and a highly validated but challenging target for the development of anticancer therapies. Novel strategies to inhibit MYC may come from understanding the co-factors it uses to drive pro-tumorigenic gene expression programs, providing their role in MYC activity is understood. Here we interrogate how one MYC co-factor, host cell factor (HCF)-1, contributes to MYC activity in a human Burkitt lymphoma setting. We identify genes connected to mitochondrial function and ribosome biogenesis as direct MYC/HCF-1 targets and demonstrate how modulation of the MYC-HCF-1 interaction influences cell growth, metabolite profiles, global gene expression patterns, and tumor growth in vivo. This work defines HCF-1 as a critical MYC co-factor, places the MYC-HCF-1 interaction in biological context, and highlights HCF-1 as a focal point for development of novel anti-MYC therapies.

Tumours form when cells lose control of their growth. Usually, cells produce signals that control how much and how often they divide. But if these signals become faulty, cells may grow too quickly or multiply too often. For example, a group of proteins known as MYC proteins activate growth genes in a cell, but too much of these proteins causes cells to grow uncontrollably. With one third of all cancer deaths linked to excess MYC proteins, these molecules could be key targets for anti-cancer drugs. However, current treatments fail to target these proteins. One option for treating cancers linked to MYC proteins could be to target proteins that work alongside MYC proteins, such as the protein HCF-1, which can attach to MYC proteins. To test if HCF-1 could be a potential drug target, Popay et al. first studied how HCF-1 and MYC proteins interacted using specific cancer cells grown in the laboratory. This revealed that when the two proteins connected, they activated genes that trigger rapid cell growth. When these cancer cells were then injected into mice, tumours quickly grew. However, when the MYC and HCF-1 attachments in the cancer cells were disrupted, the tumours shrunk. This suggests that if anti-cancer drugs were able to target HCF-1 proteins, they could potentially reduce or even reverse the growth of tumours. While further research is needed to identify drug candidates, these findings reveal a promising target for treating tumours that stem from over-abundant MYC proteins.

Geocoding rural addresses in a community contaminated by PFOA: a comparison of methods.

BACKGROUND: Location is often an important component of exposure assessment, and positional errors in geocoding may result in exposure misclassification. In rural areas, successful geocoding to a street address is limited by rural route boxes. Communities have assigned physical street addresses to rural route boxes as part of E911 readdressing projects for improved emergency response. Our study compared automated and E911 methods for recovering and geocoding valid street addresses and assessed the impact of positional errors on exposure classification. METHODS: The current study is a secondary analysis of existing data that included 135 addresses self-reported by participants of a rural community study who were exposed via public drinking water to perfluorooctanoate (PFOA) released from a DuPont facility in Parkersburg, West Virginia. We converted pre-E911 to post-E911 addresses using two methods: automated ZP4 address-correction software with the U.S. Postal Service LACS database and E911 data provided by Wood County, West Virginia. Addresses were geocoded using TeleAtlas, an online commercial service, and ArcView with StreetMap Premium North America NAVTEQ 2008 enhanced street dataset. We calculated positional errors using GPS measurements collected at each address and assessed exposure based on geocoded location in relation to public water pipes. RESULTS: The county E911 data converted 89% of the eligible addresses compared to 35% by ZP4 LACS. ArcView/NAVTEQ geocoded more addresses (n = 130) and with smaller median distance between geocodes and GPS coordinates (39 meters) than TeleAtlas (n = 85, 188 meters). Without E911 address conversion, 25% of the geocodes would have been more than 1000 meters from the true location. Positional errors in TeleAtlas geocoding resulted in exposure misclassification of seven addresses whereas ArcView/NAVTEQ methods did not misclassify any addresses. CONCLUSIONS: Although the study was limited by small numbers, our results suggest that the use of county E911 data in rural areas increases the rate of successful geocoding. Furthermore, positional accuracy of rural addresses in the study area appears to vary by geocoding method. In a large epidemiological study investigating the health effects of PFOA-contaminated public drinking water, this could potentially result in exposure misclassification if addresses are incorrectly geocoded to a street segment not serviced by public water.