Journal articles on the topic 'Optimisation hit-To-Lead'

Data from the World Health Organisation show that the global incidence of dengue infection has risen drastically, with an estimated 400 million cases of dengue infection occurring annually. Despite this worrying trend, there is still no therapeutic treatment available. Herein, we investigated short peptide fragments with a varying total number of amino acid residues (peptide fragments) from previously reported dengue virus type 2 (DENV2) peptide-based inhibitors, DN58wt (GDSYIIIGVEPGQLKENWFKKGSSIGQMF), DN58opt (TWWCFYFCRRHHPFWFFYRHN), DS36wt (LITVNPIVTEKDSPVNIEAE), and DS36opt (RHWEQFYFRRRERKFWLFFW), aided by in silico approaches: peptide–protein molecular docking and 100 ns of molecular dynamics (MD) simulation via molecular mechanics using Poisson–Boltzmann surface area (MMPBSA) and molecular mechanics generalised Born surface area (MMGBSA) methods. A library of 11,699 peptide fragments was generated, subjected to in silico calculation, and the candidates with the excellent binding affinity and shown to be stable in the DI-DIII binding pocket of DENV2 envelope (E) protein were determined. Selected peptides were synthesised using conventional Fmoc solid-phase peptide chemistry, purified by RP-HPLC, and characterised using LCMS. In vitro studies followed, to test for the peptides’ toxicity and efficacy in inhibiting the DENV2 growth cycle. Our studies identified the electrostatic interaction (from free energy calculation) to be the driving stabilising force for the E protein–peptide interactions. Five key E protein residues were also identified that had the most interactions with the peptides: (polar) LYS36, ASN37, and ARG350, and (nonpolar) LEU351 and VAL354; these residues might play crucial roles in the effective binding interactions. One of the peptide fragments, DN58opt_8-13 (PFWFFYRH), showed the best inhibitory activity, at about 63% DENV2 plague reduction, compared with no treatment. This correlates well with the in silico studies in which the peptide possessed the lowest binding energy (−9.0 kcal/mol) and was maintained steadily within the binding pocket of DENV2 E protein during the MD simulations. This study demonstrates the use of computational studies to expand research on lead optimisation of antiviral peptides, thus explaining the inhibitory potential of the designed peptides.

Emerging resistance to existing antimalarial drugs drives the search for new antimalarials, and protein translation is a promising pathway to target. Threonyl t-RNA synthetase (ThrRS) is one of the enzymes involved in this pathway, and it has been validated as an anti-malarial drug target. Here, we present 9 structurally diverse low micromolar Plasmodium falciparum ThrRS inhibitors that were identified using high-throughput virtual screening (HTVS) and were verified in a FRET enzymatic assay. Salicylic acid-based compound (LE = 0.34) was selected as a most perspective hit and was subjected to hit-to-lead optimisation. A total of 146 hit analogues were synthesised or obtained from commercial vendors and were tested. Structure-activity relationship study was supported by the crystal structure of the complex of a salicylic acid analogue with a close homologue of the plasmodium target, E. coli ThrRS (EcThrRS). Despite the availability of structural information, the hit identified via virtual screening remained one of the most potent PfThrRS inhibitors within this series. However, the compounds presented herein provide novel scaffolds for ThrRS inhibitors, which could serve as starting points for further medicinal chemistry projects targeting ThrRSs or structurally similar enzymes.

A novel flow-based approach for the preparation of benzimidazol-2-one (1) scaffold by the 1,1′-carbonyldiimidazole (CDI)-promoted cyclocarbonylation of o-phenylenediamine (2) is reported. Starting from a preliminary batch screening, the model reaction was successfully translated under flow conditions and optimised by means of design of experiment (DoE). The method allowed the efficient preparation of this privileged scaffold and to set up a general protocol for the multigram-scale preparation in high yield, purity, and productivity, and was successfully applied for the multigram flow synthesis of N-(2-chlorobenzyl)-5-cyano-benzimidazol-2-one, which is a key synthon for hit-to-lead explorations in our anti-inflammatory drug discovery program.

Parasitic worms cause very significant diseases in animals and humans worldwide, and their control is critical to enhance health, well-being and productivity. Due to widespread drug resistance in many parasitic worms of animals globally, there is a major, continuing demand for the discovery and development of anthelmintic drugs for use to control these worms. Here, we established a practical, cost-effective and semi-automated high throughput screening (HTS) assay, which relies on the measurement of motility of larvae of the barber’s pole worm (Haemonchus contortus) using infrared light-interference. Using this assay, we screened 80,500 small molecules and achieved a hit rate of 0.05%. We identified three small molecules that reproducibly inhibited larval motility and/or development (IC50 values of ~4 to 41 µM). Future work will critically assess the potential of selected hits as candidates for subsequent optimisation or repurposing against parasitic nematodes. This HTS assay has a major advantage over most previous assays in that it achieves a ≥ 10-times higher throughput (i.e., 10,000 compounds per week), and is thus suited to the screening of libraries of tens of thousands to hundreds of thousands of compounds for subsequent hit-to-lead optimisation or effective repurposing and development. The current assay should be adaptable to many socioeconomically important parasitic nematodes, including those that cause neglected tropical diseases (NTDs). This aspect is of relevance, given the goals of the World Health Organization (WHO) Roadmap for NTDs 2021–2030, to develop more effective drugs and drug combinations to improve patient outcomes and circumvent the ineffectiveness of some current anthelmintic drugs and possible drug resistance.

Fragment-based drug discovery (FBDD) has become a mainstream technology for the identification of chemical hit matter in drug discovery programs. To date, the food and drug administration has approved four drugs, and over forty compounds are in clinical studies that can trace their origins to a fragment-based screen. The challenges associated with implementing an FBDD approach are many and diverse, ranging from the library design to developing methods for identifying weak affinity compounds. In this article, we give an overview of current progress in fragment library design, fragment to lead optimisation and on the advancement in techniques used for screening. Finally, we will comment on the future opportunities and challenges in this field.

Focal adhesion kinase (FAK) is a tyrosine kinase that is overexpressed and activated in several advanced-stage solid cancers. In cancer cells, FAK promotes the progression and metastasis of tumours. In this study, we used structure-based virtual screening to filter a library of more than 210K compounds against the focal adhesion targeting FAK-focal adhesion targeting (FAT) domain to identify 25 virtual hit compounds which were screened in the invasive breast cancer line (MDA-MB-231). Most notably, compound I showed low micromolar antiproliferative activity, as well as antimigratory activity. Moreover, examination in a model of triple negative breast cancer (TNBC), revealed that, despite not effecting FAK phosphorylation, compound I significantly impairs proliferation whilst impairing focal adhesion growth and turnover leading to reduced migration. Further optimisation and synthesis of analogues of the lead compound I using a four-step synthetic procedure was performed, and analogues were assessed for their antiproliferative activity against three breast cancer (MDA-MB-231, T47D, BT474) cell lines and one pancreatic cancer (MIAPaCa2) cell line. Compound 5f was identified as a promising lead compound with IC50 values in the range of 4.59–5.28 μM in MDA-MB-231, T47D, BT474, and MIAPaCa2. Molecular modelling and pharmacokinetic studies provided more insight into the therapeutic features of this new series.

Abstract eIF4E is the rate limiting factor for cap-dependent protein translation, forming an essential part of the translation initiation complex, eIF4F and is a key signalling convergence point for the major oncogenic pathways MAPK and PI3K/AKT/MTOR. eIF4E has been shown to be overexpressed in cancer, which has been associated with poor prognosis and resistance to chemotherapeutics and targeted agents such as mTOR and MAPK inhibitors. eIF4E is therefore a promising target for cancer treatment but has so far been difficult to target with small molecules due to a lack of druggable pockets. Fragment based crystallographic screening is a powerful technique for probing the surface of proteins to identify potentially druggable binding sites. Here, we describe our fragment-based approach and hit optimisation campaign to generate potent compounds binding to eIF4E For the fragment screen, we generated an engineered form of eIF4E, where the N-terminal (residues 1-35) were removed and replaced a short, tethered peptide based on the canonical binding sequence of the eIF4E binding protein 4E-BP1, and screened 1400 fragments using a combination of Xray crystallography and NMR. Several low affinity (mM) fragment hits were identified, binding to both the mRNA cap- binding site and at an additional binding site of unknown functional relevance. Using a combination of biophysical and biochemical assays, subsequent rounds of iterative structure-based drug design of yielded potent lead molecules against both binding sites. For the cap-binding site, lead compounds of low nM potency were generated but due to the polar nature of the binding site, the molecules had very poor permeability properties and did not inhibit cell proliferation. For the non-canonical binding site, lead compounds with potency of 100nM alongside less potent enantiomers were generated which provided useful tools for probing the function of the binding site in vitro. We developed a MSD (Meso-scale discovery) assay to determine that the lead compound and not the inactive enantiomer could disrupt the eIF4E:eIF4G interaction in HeLa cell lysates with an IC50 of 1uM. Using a HeLa extract in vitro translation assay, we could also demonstrate that both the cap site and non-canonical site lead compounds could inhibit cap-dependent but not IRES driven protein translation. This work demonstrates the power of fragment screening to identify novel functional pockets on difficult to drug proteins such as eIF4E. Citation Format: Caroline J Richardson, Mladen Vincovic, Charlotte East, Nicola Wallis, George Ward, Andrew Woodhead. Fragment based discovery of inhibitors of the eIF4E:eIF4G interaction [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr A142.

Abstract My presentation will describe our work on the discovery, nonclinical antitumor properties, mechanism of action (MOA), identification of initial target patient population, and early clinical development of NXP-800. We discovered this agent in our academic drug discovery centre at ICR following our initial identification of the ‘bisamide’ hit CCT245232 from a diverse ~200,000-compound library using an innovative, imaging-based (ArrayScan™) phenotypic screen for inhibitors of the HSF1-mediated activation of the heat shock response in U2OS human osteosarcoma cells. Subsequent multiparameter medicinal chemistry optimisation of the bisamide series, containing the N,N′-4-methyl-1,3-phenylenediamide core, focused on establishing the cell-based SAR for both inhibition of cell proliferation and linked HSF-1 mediated HSP72 induction in the sensitive ARID1A-mutant, platinum-resistant SK-OV-3 human ovarian carcinoma cell line. This generated our orally bioavailable, in vivo-active lead compound and chemical tool CCT251236 – exhibiting oral antitumor efficacy in the SK-OV-3 human ovarian cancer xenograft model in nude mice (Cheeseman et al J Med Chem 60 180-201 2017). Final multiparameter optimization yielded the clinical development candidate CCT361814/NXP800 (Pasqua et al J Med Chem 66 5907-36 2023). With the screening hit bisamide compound already active in the single to low double digit nanomolar range, the early focus was on improving kinetic solubility while retaining the desired antiproliferative and linked HSF1 pathway inhibitory activity together with simultaneous optimisation of PK/PD properties to maximize oral antitumour efficacy; finally requiring modification to the fluorobisamide NXP800 to eliminate PGP-mediated efflux and achieve optimal PK/PD, Pharmacologic Audit Trail, antitumor efficacy and tolerability. In view of these properties, its clean safety panel profile, clear therapeutic index and acceptable dose-to-human prediction, NXP800 was progressed into clinical development. Evaluation in a mini-panel of human cancer cell lines and tumor xenografts revealed high sensitivity to NXP800 in ARIDIA-deficient human ovarian cancer models, confirmed in the large Sanger cancer cell line panel and in isogenic pair systems. Activity exceeded that of cisplatin in both platinum-sensitive and platinum-resistant ARID1A-mutant ovarian cancer xenograft models. By RNA-Seq we identified two sets of consistent, major gene expression profile changes in human cancer cell lines exposed to NXP800, namely: 1) the expected changes in HSF1-regulated genes, together with 2) activation of the integrated stress response (ISR), including ATF4-regulated gene expression. This latter did not indicate a global stress response to NXP800 as we saw no activation of the unfolded protein response (UPR). Physiologically, ISR activation is mediated by phosphorylation of EIF2α which is tightly regulated by four stress-controlled kinases, GCN2, HRI, PKR and PERK. Using each of systematic siRNA knockdown or pharmacologic inhibition by two small-molecule tool compounds from different chemotypes, we discovered that GCN2 alone was necessary and sufficient for ISR activation and cell growth inhibition by NXP800 in SK-OV-3 ovarian cancer cells. Also, orthogonal siRNA depletion or pharmacologic inhibition of GCN2 both markedly reduced the antiproliferative activity of NXP800 in these cells. Global phospho-proteome analysis demonstrated defined changes in response to NXP800 which were reversed by co-treatment with a GCN2 inhibitor. Other follow-on studies at the protein level demonstrated that pharmacological concentrations of NXP800 induced GCN2-dependent phosphorylation of EIF2α, inhibition of global cap-dependent protein translation, and selective translation of ATF4 – a transcription factor that activates downstream genes such as CHAC1 and CHOP in the ISR – both in ARID1A-mutant human ovarian cells in vitro and in corresponding tumor xenograft models in vivo. Using siRNA silencing, we showed that prevention of ATF4 induction substantially reduced the antiproliferative response of SK-OV-3 human ovarian carcinoma cells to NXP800 treatment. Controls used in these experiments included a closely matched, inactive regioisomer. Furthermore, we showed that ISR induction by NXP800 inhibited HSF1 activation, in SK-OV-3 cells, confirming the mechanistic link between ISR activation and inhibition of HSF1-mediated transcription. We further showed that GCN2 activation was not due to the canonical mechanism of amino acid starvation. In summary, we used an HSF1 pathway-focused phenotypic screen to discover the mechanistically novel, first-in-class drug NXP800, which acts potently on ARID1A-mutant, human ovarian cancer cells to stimulate GCN2 and thereby activate the ISR pathway, leading to ATF4 induction and inhibition of HSF1-mediated gene transcription in ARID1A-mutant, platinum-resistant human ovarian cancer cells. Through this mechanism, NXP800 shows highly promising activity in models of this cancer type, including potent inhibition of proliferation in vitro and substantial regression of tumor xenografts in vivo. Studies are currently underway to determine precisely how NXP800 stimulates GCN2 activity and the role of ARID1A deficiency in its pharmacological effects. Recent ChIP-Seq studies are informing on the molecular interactions between ARID1A mutation and the expression of ISR/ATF4 and HSF1-regulated genes. With Nuvectis Pharma, the Phase 1a dose escalation study has been completed and a multicentre Phase 1b expansion cohort study in ARID1A-mutated, platinum-resistant ovarian cancer – a high unmet medical need – has been initiated (NCT05226507) in collaboration with the GOG Foundation and the European Network of Gynaecological Oncological Trial Group (ENGOT). FDA has issued a Fast Track designation to NXP800 in this setting. In addition, NXP800 shows therapeutic potential in non-clinical models of endometrial, gastro-intestinal and bile duct cancer, with FDA Orphan Drug status granted in the last of these indications. Citation Format: Paul Workman. From targeted phenotypic screen to NXP800: A clinical stage activator of the integrated stress response for the treatment of ARID1A-mutated ovarian carcinoma [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr IA014.

The new ALICE Inner Tracking System is the first large-scale MAPS-based tracking system. It is covering an active surface of 10 m2, with a total of 12.5 billion pixels. Several optimisations of the pixel chip lead to a quasi-noise-free operation, with measured fake-hit rates of below 1 hit per pixel and billion events (system level numbers), numbers compatible with the order of magnitude expected from cosmic and natural background radiation. This contribution covers a detailed study of fake hits as recorded in the inner-most detector barrels, made of the highest quality chips. It reveals a localised noise pattern that could be traced down to originate from decoupling capacitors present on the detector module. It can most likely be explained by the radioactive decay of 210Pb, which is present in trace amounts in the solder that was used to mount decoupling capacitors on the detector modules. This hypothesis is substantiated with a dedicated simulation study and laboratory measurements.

AbstractQSAR methods are widely applied in the drug discovery process, both in the hit‐to‐lead and lead optimization phase, as well as in the drug-approval process. Most QSAR algorithms are limited to using molecules as input and disregard pharmacophores or pharmacophoric features entirely. However, due to the high level of abstraction, pharmacophore representations provide some advantageous properties for building quantitative SAR models. The abstract depiction of molecular interactions avoids a bias towards overrepresented functional groups in small datasets. Furthermore, a well‐crafted quantitative pharmacophore model can generalise to underrepresented or even missing molecular features in the training set by using pharmacophoric interaction patterns only. This paper presents a novel method to construct quantitative pharmacophore models and demonstrates its applicability and robustness on more than 250 diverse datasets. fivefold cross-validation on these datasets with default settings yielded an average RMSE of 0.62, with an average standard deviation of 0.18. Additional cross-validation studies on datasets with 15–20 training samples showed that robust quantitative pharmacophore models could be obtained. These low requirements for dataset sizes render quantitative pharmacophores a viable go-tomethod for medicinal chemists, especially in the lead-optimisation stage of drug discovery projects.

IntroductionAs antibiotic resistance has become more prevalent, the social and economic impacts are increasingly pressing. Indeed, bacteria have developed the SOS response which facilitates the evolution of resistance under genotoxic stress. The transcriptional repressor, LexA, plays a key role in this response. Mutation of LexA to a non-cleavable form that prevents the induction of the SOS response sensitizes bacteria to antibiotics. Achieving the same inhibition of proteolysis with small molecules also increases antibiotic susceptibility and reduces drug resistance acquisition. The availability of multiple LexA crystal structures, and the unique Ser-119 and Lys-156 catalytic dyad in the protein enables the rational design of inhibitors.MethodsWe pursued a binary approach to inhibit proteolysis; we first investigated β-turn mimetics, and in the second approach we tested covalent warheads targeting the Ser-119 residue. We found that the cleavage site region (CSR) of the LexA protein is a classical Type II β-turn, and that published 1,2,3-triazole compounds mimic the β-turn. Generic covalent molecule libraries and a β-turn mimetic library were docked to the LexA C-terminal domain using molecular modelling methods in FlexX and CovDock respectively. The 133 highest-scoring molecules were screened for their ability to inhibit LexA cleavage under alkaline conditions. The top molecules were then tested using a RecA-mediated cleavage assay.ResultsThe β-turn library screen did not produce any hit compounds that inhibited RecA-mediated cleavage. The covalent screen discovered an electrophilic serine warhead that can inhibit LexA proteolysis, reacting with Ser-119 via a nitrile moiety. DiscussionThis research presents a starting point for hit-to-lead optimisation, which could lead to inhibition of the SOS response and prevent the acquisition of antibiotic resistance.

According to the World Health Organisation (WHO), as of week 23 of 2022, there were more than 1,311 cases of dengue in Malaysia, with 13 deaths reported. Furthermore, there was an increase of 65.7% during the same period in 2021. Despite the increase in cumulative dengue incidence, there is no effective antiviral drug available for dengue treatment. This work aimed to evaluate several nitro-benzylidene phenazine compounds, especially those that contain 4-hydroxy-3,5-bis((2-(4-nitrophenyl)hydrazinylidene)-methyl)benzoate through pharmacophore queries selection method as potential dengue virus 2 (DENV2) NS2B-NS3 protease inhibitors. Herein, molecular docking was employed to correlate the energies of selected hits’ free binding and their binding affinities. Pan assay interference compounds (PAINS) filter was also adopted to identify and assess the drug-likeness, toxicity, mutagenicity potentials, and pharmacokinetic profiles to select hit compounds that can be considered as lead DENV2 NS2B-NS3 protease inhibitors. Molecular dynamics assessment of two nitro-benzylidene phenazine derivatives bearing dinitro and hydroxy groups at the benzylidene ring showed their stability at the main binding pocket of DENV2 protease, where their MM-PBSA binding energies were between -22.53 and -17.01 kcal/mol. This work reports those two nitro-benzylidene phenazine derivatives as hits with 52–55% efficiency as antiviral candidates. Therefore, further optimisation is required to minimise the lead compounds’ toxicity and mutagenicity.

It has been fifteen months since the World Health Organisation declared the COVID-19 outbreak a global pandemic and the first lockdowns went into effect, dramatically changing the social landscape for millions of individuals worldwide. Overnight, it seemed, Zoom became the default platform for video conferencing, rapidly morphing from brand name to eponymous generic—a verb and a place and mode of being all at once. This nearly ubiquitous transition to remote work and remote play was both unprecedented and entirely anticipated. While teleworking, digital commerce, online learning, and social networking were common fare by 2020, in March of that year telepresence shifted from option to mandate, and Zooming became a daily practice for tens of millions of individuals worldwide. In an era of COVID-19, our relationships and experiences are deeply intertwined with our ability to “Zoom”. This shift resulted in new forms of artistic practice, new modes of pedagogy, and new ways of social organising, but it has also created new forms (and exacerbated existing forms) of exploitation, inequity, social isolation, and precarity. For millions, of course, lockdowns and restrictions had a profound impact that could not be mitigated by the mediated presence offered by way of Zoom and other video conferencing platforms. For those of us fortunate enough to maintain a paycheck and engage in work remotely, Zoom in part highlighted the degree to which a network logic already governed our work and our labour within a neoliberal economy long before the first lockdowns began. In the introduction to The Postmodern Condition: A Report on Knowledge, Lyotard identifies a “logic of maximum performance” that regulates the contemporary moment: a cybernetic framework for understanding what it means to communicate—one that ultimately frames all political, social, and personal interactions within matrices of power laid out in terms of performativity and optimisation (xxiv.) Performativity serves as a foundation for not only how a system operates, but for how all other elements within that system express themselves. Lyotard writes, “even when its rules are in the process of changing and innovations are occurring, even when its dysfunctions (such as strikes, crises, unemployment, or political revolutions) inspire hope and lead to a belief in an alternative, even then what is actually taking place is only an internal readjustment, and its results can be no more than an increase in the system’s ‘viability’” (11-12). One may well add to this list of dysfunctions global pandemics. Zoom, in effect, offered universities, corporations, mass media outlets, and other organisations a platform to “innovate” within an ongoing network logic of performativity: to maintain business as usual in a moment in which nothing was usual, normal, or functional. Zoom foregrounds performativity in other senses as well, to the extent that it provides a space and context for social performance. In The Presentation of Self in Everyday Life, Erving Goffman explores how social actors move through their social environments, managing their identities in response to the space in which they find themselves and the audience (who are also social actors) within those spaces. For Goffman, the social environment provides the primary context for how and why social actors behave the way that they do. Goffman further denotes different spaces where our performances may shift: from public settings to smaller audiences, to private spaces where we can inhabit ourselves without any performance demands. The advent of social media, however, has added new layers to how we understand performance, audience, and public and private social spaces. Indeed, Goffman’s assertion that we are constantly managing our impressions feels particularly accurate when considering the added pressures of managing our identities in multiple social spaces, both face to face and online. Thus, when the world shut down during the COVID-19 pandemic, and all forms of social interactions shifted to digital spaces, the performative demands of working from home became all the more complex in the sharp merging of private and public spaces. Thus, discussions and debates arose regarding proper “Zoom etiquette”, for different settings, and what constituted work-appropriate attire when working from home (a debate that, unsurprisingly, became particularly gendered in nature). Privacy management was a near constant narrative as we began asking, who can be in our spaces? How much of our homes are we required to put on display to other classmates, co-workers, and even our friends? In many ways, the hyper-dependence on Zoom interactions forced an entry into the spaces that we so often kept private, leaving our social performances permanently on display. Prior to COVID-19, the networks of everyday life had already produced rather porous boundaries between public and private life, but for the most part, individuals managed to maintain some sort of partition between domestic, intimate spaces, and their public performances of their professional and civic selves. It was an exception in The Before Times, for example, for a college professor to be interrupted in the midst of his BBC News interview by his children wandering into the room; the suspended possibility of the private erupting in the midst of a public social space (or vice versa) haunts all of our network interactions, yet the exceptionality of these moments speaks to the degree to which we sustained an illusion of two distinct stages for performance in a pre-pandemic era. Now, what was once the exception has become the rule. As millions of individuals found themselves Zooming from home while engaging co-workers, clients, patients, and students in professional interactions, the interpenetration of the public and private became a matter of daily fare. And yes, while early on in the pandemic several newsworthy (or at least meme-worthy) stories circulated widely on mass media and social media alike, serving as teleconferencing cautionary tales—usually involving sex, drugs, or bowel movements—moments of transgressive privacy very much became the norm: we found ourselves, in the midst of the workday, peering into backgrounds of bedrooms and kitchens, examining decorations and personal effects, and sharing in the comings and goings of pets and other family members entering and leaving the frame. Some users opted for background images or made use of blurring effects to “hide the mess” of their daily lives. Others, however, seemed to embrace the blur itself, implicitly or explicitly accepting the everydayness of this new liminality between public and private life. And while we acknowledge the transgressive nature of the incursions of the domestic and the intimate into workplace activities, it is worth noting as well that this incursion likewise takes place in the opposite direction, as spaces once designated as private became de facto workplace settings, and fell under the purview of a whole range of workplace policies that dictated appropriate and inappropriate behaviour. Not least of these intrusions are the literal and ideological apparatuses of surveillance that Zoom and other video conferencing platforms set into motion. In the original conception of the Panopticon, the observer could see the observed, but those being observed could not see their observers. This was meant to instill a sense of constant surveillance, whether the observer was there or not. In Discipline and Punish, Foucault considered those observed through the Panopticon as objects to be observed, with no power to turn the gaze back towards the structures of power that infiltrated their existence with such invasive intent. With Zoom, however, as much as private spaces have been infiltrated by work, school, and even family and friends, those leading classes or meetings may also feel a penetrative gaze by those who observe their professional performances, as many online participants have pushed back against these intrusions with cameras and audio turned off, leaving the performer with an audience of black screens and no indication of real observers behind them or not. In these unstable digital spaces, we vacillate between observed and observer, with the lines between private and public, visible and invisible, utterly blurred. Yet we should not lose sight of the fact that the panoptic power of the platform itself is hardly optic and remains one degree removed from its users, at the level of data extraction, collection, and exchange. In an already data-dependent era, more privacy and personal data has become available than ever before through online monitoring and the constant use of Zoom in work and social interactions. Such incursions of informatic biopower require further consideration within an emerging discussion of digital capital. There has also been the opportunity for these transformative, digital spaces to be used for an invited gaze into artistic and imaginative spaces. The global pandemic hit many industries hard, but in particular, artists and performers, as well as their performance venues, saw a massive loss of space, audiences, and income. Many artists developed performance spaces through online video conferencing in order to maintain their practice and their connection to their audiences, while others developed new curriculums and worked to find accessible ways for community members to participate in online art programming. Thus, though performers may still be faced with black squares as their audience, the invited gaze allows for artistic performances to continue, whether as digital shorts, live streamed music sets, or isolated cast members performing many roles with a reduced cast list. Though the issue of access to the technology and bandwidth needed to partake in these performances and programming is still front of mind, the presentation of artistic performances through Zoom has allowed in many other ways for a larger audience reach, from those who may not live near a performance centre, to others who may not be able to access physical spaces comfortably or safely. The ideology of ongoing productivity and expanded, remote access baked into video conferencing platforms like Zoom is perhaps most apparent in the assumptions of access that accompanied the widespread use of these platforms, particularly in the context of public institutions such as schools. In the United States, free market libertarian think tanks like the Cato Institute have pointed to the end of “Net Neutrality” as a boon for infrastructure investment that led to greater broadband access nationwide (compared to a more heavily regulated industry in Europe). Yet even policy think tanks such as the Information Technology and Innovation Foundation—with its mission to “formulate, evaluate, and promote policy solutions that accelerate innovation and boost productivity to spur growth, opportunity, and progress”—acknowledged that although the U.S. infrastructure supported the massive increase in bandwidth demands as schools and businesses went online, gaps in rural access and affordability barriers for low income users mean that more needs to be done to bring about “a more just and effective broadband network for all Americans”. But calls for greater access are, in effect, supporting this same ideological framework in which greater access presumably equates with greater equity. What the COVID-19 pandemic revealed, we would argue, is the degree to which those most in need of services and support experience the greatest degree of digital precarity, a point that Jenny Kennedy, Indigo Holcombe-James, and Kate Mannell foreground in their piece “Access Denied: How Barriers to Participate on Zoom Impact on Research Opportunity”. As they note, access to data and devices provide a basic threshold for participation, but the ability to deploy these tools and orient oneself toward these sorts of engagements suggests a level of fluency beyond what many high-risk/high-need populations may already possess. Access reveals a disposition toward global networks, and as such signals one’s degree of social capital within a network society—a “state nobility” for the digital age (Bourdieu.) While Zoom became the default platform for a wide range of official and institutional practices, from corporate meetings to college class sessions, we have seen over the past year unanticipated engagements with the platform as well. Zoombombing offers one form of evil media practice that disrupts the dominant performativity logic of Zoom and undermines the assumptions of rational exchange that still drive much of how we understand “effective” communication (Fuller and Goffey). While we may be tempted to dismiss Zoombombing and other forms of “shitposting” as “mere” trollish distractions, doing so does not address the political agency of strategic actions on these platforms that refuse to abide by “an intersubjective recognition that is based on a consensus about values or on mutual understanding” (Habermas 12). Kawsar Ali takes up these tactical uses in “Zoom-ing in on White Supremacy: Zoom-Bombing Anti-Racism Efforts” and explores how alt-right and white supremacist groups have exploited these strategies not only as a means of disruption but as a form of violence against participants. A cluster of articles in this issue take up the question of creative practice and how video conferencing technologies can be adapted to performative uses that were perhaps not intended or foreseen by the platform’s creators. xtine burrough and Sabrina Starnaman offer up one such project in “Epic Hand Washing: Synchronous Participation and Lost Narratives”, which paired live performances of handwashing in domestic spaces with readings from literary texts that commented upon earlier pandemics and plagues. While Zoom presents itself as a tool to keep a neoliberal economy flowing, we see modes of use such as burrough’s and Starnaman’s performative piece that are intentionally playful, at the same time that they attempt to address the lived experiences of lockdown, confinement, and hygienic hypervigilance. Claire Parnell, Andrea Anne Trinidad, and Jodi McAlister explore another form of playful performance through their examination of the #RomanceClass community in the Philippines, and how they adapted their biannual reading and performance events of their community-produced English-language romance fiction. While we may still use comparative terms such as “face-to-face” and “virtual” to distinguish between digitally-mediated and (relatively) unmediated interactions, Parnell et al.’s work highlights the degree to which these technologies of mediation were already a part of this community’s attempt to support and sustain itself. Zoom, then, became the vehicle to produce and share community-oriented kilig, a Filipino term for embodied, romantic affective response. Shaun Wilson’s “Creative Practice through Teleconferencing in the Era of COVID-19” provides another direct reflection on the contemporary moment and the framing aesthetics of Zoom. Through an examination of three works of art produced for screen during the COVID-19 pandemic, including his own project “Fading Light”, Wilson examines how video conferencing platforms create “oscillating” frames that speak to and comment on each other at the same time that they remain discrete and untouched. We have opened and closed this issue with bookends of sorts, bringing to the fore a range of theoretical considerations alongside personal reflections. In our feature article, “Room without Room: Affect and Abjection in the Circuit of Self-Regard”, Ricky Crano examines the degree to which the aesthetics of Zoom, from its glitches to its default self-view, create modes of interaction that drain affect from discourse, leaving its users with an impoverished sense of co-presence. His focus is explicitly on the normative uses of the platform, not the many artistic and experimental misappropriations that the platform likewise offers. He concludes, “it is left to artists and other experimenters to expose and undermine the workings of power in the standard corporate, neoliberal modes of engagement”, which several of the following essays in this issue then take up. And we close with “Embracing Liminality and ‘Staying with the Trouble’ on (and off) Screen”, in which Tania Lewis, Annette Markham, and Indigo Holcombe-James explore two autoethnographic studies, Massive and Microscopic Sensemaking and The Shut-In Worker, to discuss the liminality of our experience of the COVID-19 pandemic, on and off—and in between—Zoom screens. Rather than suggesting a “return to normal” as mask mandates, social distancing, and lockdown restrictions ease, they attempt to “challenge the assumption that stability and certainty is what we now need as a global community … . How can we use the discomfort of liminality to imagine global futures that have radically transformative possibilities?” This final piece in the collection we take to heart, as we consider how we, too, can stay in the trouble, and consider transformative futures. Each of these pieces offers a thoughtful contribution to a burgeoning discussion on what Zooming means to us as academics, teachers, researchers, and community members. Though investigations into the social effects of digital spaces are not new, this moment in time requires careful and critical investigation through the lens of a global pandemic as it intersects with a world that has never been more digital in its presence and social interactions. The articles in this volume bring us to a starting point, but there is much more to cover: issues of disability and accessibility, gender and physical representations, the political economy of digital accessibility, the transformation of learning styles and experiences through a year of online learning, and still more areas of investigation to come. It is our hope that this volume provides a blueprint of sorts for other critical engagements and explorations of how our lives and our digital landscapes have been impacted by COVID-19, regardless of the instability of our connections. We would like to thank all of the contributors and peer reviewers who made this fascinating issue possible, with a special thanks to the Cultural Studies Association New Media and Digital Cultures Working Group, where these conversations started … on Zoom, of course. References Bourdieu, Pierre. The State Nobility. Stanford UP, 1998. Brake, Doug. “Lessons from the Pandemic: Broadband Policy after COVID-19.” Information Technology and Innovation Foundation, 13 July 2020. <http://itif.org/publications/2020/07/13/lessons-pandemic-broadband-policy-after-covid-19>. “Children Interrupt BBC News Interview – BBC News.” BBC News, 10 Mar. 2017. <http://youtu.be/Mh4f9AYRCZY>. Firey, Thomas A. “Telecommuting to Avoid COVID-19? 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