Implementing and evaluating online advance care planning training in UK nursing homes during COVID-19: findings from the Necessary Discussions multi-site case study project.

BACKGROUND: Advance care planning in nursing homes is important to ensure the wishes and preferences of residents are recorded, especially during the COVID-19 pandemic. However, care staff and family members frequently report feeling unprepared for these conversations. More resources are needed to support them with these necessary discussions. This research aimed to develop, implement and evaluate a website intervention for care staff and family members to provide training and information about advance care planning during COVID-19. METHODS: The research was a primarily qualitative case study design, comprising multiple UK nursing home cases. Data collection included semi-structured interviews with care staff and family members which were coded and analysed thematically. A narrative synthesis was produced for each case, culminating in a thematic cross-case analysis of the total findings. Theoretical propositions were refined throughout the research. RESULTS: Eight nursing homes took part in the study, involving 35 care staff and 19 family members. Findings were reported according to the RE-AIM framework which identified the reach, effectiveness, adoption, implementation and maintenance of the intervention. Themes included: website content that was well received; suggestions for improvement; implementation barriers and facilitators; examples of organisational and personal impact. CONCLUSIONS: Four theoretical propositions relating to advance care planning in nursing homes are presented, relating to: training and information needs, accessibility, context, and encouraging conversations. Implications for practice and training include an awareness of diverse learning styles, re-enforcing the right to be involved in advance care planning and encouraging opportunities for facilitated discussion. TRIAL REGISTRATION: ISRCTN registry (ID 18003630 ) on 19.05.21.

Comprehensive nucleosome interactome screen establishes fundamental principles of nucleosome binding.

Nuclear proteins bind chromatin to execute and regulate genome-templated processes. While studies of individual nucleosome interactions have suggested that an acidic patch on the nucleosome disk may be a common site for recruitment to chromatin, the pervasiveness of acidic patch binding and whether other nucleosome binding hot-spots exist remain unclear. Here, we use nucleosome affinity proteomics with a library of nucleosomes that disrupts all exposed histone surfaces to comprehensively assess how proteins recognize nucleosomes. We find that the acidic patch and two adjacent surfaces are the primary hot-spots for nucleosome disk interactions, whereas nearly half of the nucleosome disk participates only minimally in protein binding. Our screen defines nucleosome surface requirements of nearly 300 nucleosome interacting proteins implicated in diverse nuclear processes including transcription, DNA damage repair, cell cycle regulation and nuclear architecture. Building from our screen, we demonstrate that the Anaphase-Promoting Complex/Cyclosome directly engages the acidic patch, and we elucidate a redundant mechanism of acidic patch binding by nuclear pore protein ELYS. Overall, our interactome screen illuminates a highly competitive nucleosome binding hub and establishes universal principles of nucleosome recognition.

Novel Functions and Virus-Host Interactions Implicated in Pathogenesis and Replication of Human Herpesvirus 8.

Human herpesvirus 8 (HHV-8) is classified as a γ2-herpesvirus and is related to Epstein-Barr virus (EBV), a γ1-herpesvirus. One important aspect of the γ-herpesviruses is their association with neoplasia, either naturally or in animal model systems. HHV-8 is associated with B-cell-derived primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD), endothelial-derived Kaposi's sarcoma (KS), and KSHV inflammatory cytokine syndrome (KICS). EBV is also associated with a number of B-cell malignancies, such as Burkitt's lymphoma, Hodgkin's lymphoma, and posttransplant lymphoproliferative disease, in addition to epithelial nasopharyngeal and gastric carcinomas. Despite the similarities between these viruses and their associated malignancies, the particular protein functions and activities involved in key aspects of virus biology and neoplastic transformation appear to be quite distinct. Indeed, HHV-8 specifies a number of proteins for which counterparts had not previously been identified in EBV, other herpesviruses, or even viruses in general, and these proteins are believed to play vital functions in virus biology and to be involved centrally in viral pathogenesis. Additionally, a set of microRNAs encoded by HHV-8 appears to modulate the expression of multiple host proteins to provide conditions conductive to virus persistence within the host and possibly contributing to HHV-8-induced neoplasia. Here, we review the molecular biology underlying these novel virus-host interactions and their potential roles in both virus biology and virus-associated disease.

Developing and evaluating online COVID-centric advance care planning training and information resources for nursing staff and family members in nursing homes: the necessary discussions study protocol.

BACKGROUND: Nursing home residents are typically older adults with high levels of chronic illness and impairment. As such, they are particularly susceptible to severe complications and mortality from COVID-19. Since all nursing home residents are at increased risk, nursing home care staff need to know what residents would want to happen should they become infected with COVID-19. This study aims to develop and evaluate advance care planning (ACP) COVID-centric online training and information resources for nursing home staff and family members of residents, to improve care at the end of life during a COVID-19 outbreak. Based on the findings we will develop implementation guidelines for nursing homes to ensure wider impact and application during the pandemic and beyond. METHODS: The content of the training and information resources will be based on a rapid review of literature and guidance on ACP in the context of COVID-19 and consultation with the study expert reference group. An integrated communications company will then work alongside the research team to design the online training and information resources. To evaluate the resources, we will employ a multiple case study design where a nursing home (defined as an institutional setting in which nursing care is provided to older adults on-site 24 h a day) will be the unit of analysis or 'case'. The RE-AIM (reach, effectiveness, adoption, implementation, maintenance) framework will guide the evaluation of implementation of the training and information resources. We will recruit and interview staff and family members from between 6 and 9 nursing homes across Northern Ireland, England and Scotland and gather quantitative data from a feedback survey included in the training and information resources. DISCUSSION: The Necessary Discussions study is very timely given the challenging experiences of nursing homes, their staff, residents and their family members during the COVID-19 pandemic. It meets a key need and addresses an important gap in research and practice. The training and information resources will be 'COVID-centric', but they will also have a longstanding relevance for future ACP practice in UK care homes. TRIAL REGISTRATION: ISRCTN registry ( ID 18003630 ) on 19.05.21.

Ethical care during COVID-19 for care home residents with dementia.

The COVID-19 pandemic has had a devastating impact on care homes in the United Kingdom, particularly for those residents living with dementia. The impetus for this article comes from a recent review conducted by the authors. That review, a qualitative media analysis of news and academic articles published during the first few months of the outbreak, identified ethical care as a key theme warranting further investigation within the context of the crisis. To explore ethical care further, a set of salient ethical values for delivering care to care home residents living with dementia during the pandemic was derived from a synthesis of relevant ethical standards, codes and philosophical approaches. The ethical values identified were caring, non-maleficence, beneficence, procedural justice, dignity in death and dying, well-being, safety, and personhood. Using these ethical values as a framework, alongside examples from contemporaneous media and academic sources, this article discusses the delivery of ethical care to care home residents with dementia within the context of COVID-19. The analysis identifies positive examples of ethical values displayed by care home staff, care sector organisations, healthcare professionals and third sector advocacy organisations. However, concerns relating to the death rates, dignity, safety, well-being and personhood - of residents and staff - are also evident. These shortcomings are attributable to negligent government strategy, which resulted in delayed guidance, lack of resources and Personal Protective Equipment, unclear data, and inconsistent testing. Consequently, this review demonstrates the ways in which care homes are underfunded, under resourced and undervalued.

Human herpesvirus 8 viral interleukin-6 signaling through gp130 promotes virus replication in primary effusion lymphoma and endothelial cells.

The contributions of human herpesvirus 8 (HHV-8) viral interleukin-6 (vIL-6) to virus biology remain unclear. Here we examined the role of vIL-6/gp130 signaling in HHV-8 productive replication in primary effusion lymphoma and endothelial cells. Depletion and depletion-complementation experiments revealed that endoplasmic reticulum-localized vIL-6 activity via gp130 and gp130-activated signal transducer and activator of transcription (STAT) signaling, but not extracellular signal-regulated kinase (ERK) activation, was critical for vIL-6 proreplication activity. Our data significantly extend current understanding of vIL-6 function and associated mechanisms in HHV-8 biology.

Role of human herpesvirus 8 interleukin-6-activated gp130 signal transducer in primary effusion lymphoma cell growth and viability.

Human herpesvirus 8 (HHV-8) infection is associated with Kaposi's sarcoma, primary effusion lymphoma (PEL), and multicentric Castleman's disease. HHV-8-encoded viral interleukin-6 (vIL-6) is believed to contribute to pathogenesis via proproliferative, antiapoptotic, and proangiogenic activities. In PEL cells, vIL-6 is produced in functional amounts during viral latency and promotes the growth of these cells, mediating its activity from the endoplasmic reticulum (ER), where it is predominantly localized. This vIL-6 activity is dependent, in part, on its interaction with a splice variant of vitamin K epoxide reductase complex subunit 1 (VKORC1), termed VKORC1 variant 2 (VKORC1v2). Here we report that the IL-6 signal transducer, gp130, which can support vIL-6 signaling from the ER, is also required for optimal PEL cell growth and viability. Levels of activated extracellular regulated kinases (ERKs) 1 and 2 and signal transducer and activator of transcription 1 (STAT1) and STAT3, phosphorylated following gp130 stimulation, were reduced in gp130-depleted BCBL-1 and BC-1 cells. Diminished STAT activation was also detected in JSC-1 and BC-3 cells. Effects of gp130 depletion on growth could be mimicked by short hairpin RNA targeting of ERKs 1 and 2 or by depletion of STAT3. Finally, inhibition of vIL-6-gp130 association specifically within the ER compartment suppressed cell proliferation and viability, mirroring the effects of gp130 depletion. Combined, these data demonstrate that gp130, in addition to VKORC1v2, is essential for normal PEL cell growth and survival and that ER-localized vIL-6-gp130 interactions are critical for these activities. Targeting of intracellular vIL-6-gp130 interactions could potentially provide a means of PEL therapy.

Molecular biology of human herpesvirus 8: novel functions and virus-host interactions implicated in viral pathogenesis and replication.

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), is the second identified human gammaherpesvirus. Like its relative Epstein-Barr virus, HHV-8 is linked to B-cell tumors, specifically primary effusion lymphoma and multicentric Castleman's disease, in addition to endothelial-derived KS. HHV-8 is unusual in its possession of a plethora of "accessory" genes and encoded proteins in addition to the core, conserved herpesvirus and gammaherpesvirus genes that are necessary for basic biological functions of these viruses. The HHV-8 accessory proteins specify not only activities deducible from their cellular protein homologies but also novel, unsuspected activities that have revealed new mechanisms of virus-host interaction that serve virus replication or latency and may contribute to the development and progression of virus-associated neoplasia. These proteins include viral interleukin-6 (vIL-6), viral chemokines (vCCLs), viral G protein-coupled receptor (vGPCR), viral interferon regulatory factors (vIRFs), and viral antiapoptotic proteins homologous to FLICE (FADD-like IL-1ß converting enzyme)-inhibitory protein (FLIP) and survivin. Other HHV-8 proteins, such as signaling membrane receptors encoded by open reading frames K1 and K15, also interact with host mechanisms in unique ways and have been implicated in viral pathogenesis. Additionally, a set of micro-RNAs encoded by HHV-8 appear to modulate expression of multiple host proteins to provide conditions conducive to virus persistence within the host and could also contribute to HHV-8-induced neoplasia. Here, we review the molecular biology underlying these novel virus-host interactions and their potential roles in both virus biology and virus-associated disease.

Human herpesvirus 8 viral interleukin-6 interacts with splice variant 2 of vitamin K epoxide reductase complex subunit 1.

Viral interleukin-6 (vIL-6) specified by human herpesvirus 8 is, unlike its cellular counterpart, secreted very inefficiently and can signal via vIL-6(2):gp130(2) signaling complexes from the endoplasmic reticulum (ER) compartment. Intracellular, autocrine activities of vIL-6 are important for proproliferative and prosurvival activities of the viral cytokine in latently infected primary effusion lymphoma (PEL) cells. However, the molecular determinants of vIL-6 ER localization and function are unclear. Using yeast two-hybrid analysis, we identified the database-documented but uncharacterized splice variant of vitamin K epoxide reductase complex subunit 1 (VKORC1), termed VKORC1 variant 2 (VKORC1v2), as a potential interaction partner of vIL-6. In transfected cells, epitope-tagged VKORC1v2 was found to localize to the ER, to adopt a single-transmembrane (TM) topology placing the C tail in the ER lumen, and to bind vIL-6 via these sequences. Deletion mutagenesis and coprecipitation assays mapped the vIL-6-binding domain (vBD) of VKORC1v2 to TM-proximal residues 31 to 39. However, while sufficient to confer vIL-6 binding to a heterologous protein, vBD was unable to induce vIL-6 secretion when fused to (secreted) hIL-6, suggesting a VKORC1v2-independent mechanism of vIL-6 ER retention. In functional assays, overexpression of ER-directed vBD led to suppression of PEL cell proliferation and viability, effects also mediated by VKORC1v2 depletion and, as reported previously, by vIL-6 suppression. The growth-inhibitory and proapoptotic effects of VKORC1v2 depletion could be rescued by transduced wild-type VKORC1v2 but not by a vIL-6-refractory vBD-altered variant, indicating the functional relevance of the vIL-6-VKORC1v2 interaction. Notably, gp130 signaling was unaffected by VKORC1v2 or vBD overexpression or by VKORC1v2 depletion, suggesting an alternative pathway of vIL-6 activity via VKORC1v2. Combined, our data identify a novel and functionally significant interaction partner of vIL-6 that could potentially be targeted for therapeutic benefit.

'Four walls and a garden': Exploring the experiences of families affected by dementia during the COVID-19 pandemic.

INTRODUCTION: When the first national COVID-19 lockdown came into effect in the UK in March 2020, life changed significantly. Some services and social contacts for people with dementia and their families stopped, while others, for example, peer support, moved online. This research explored the experiences of families affected by dementia during the pandemic, specifically those living in the community. AIMS: In partnership with a community dementia charity, this study sought to gain an understanding of the experiences of people with dementia and family carers during the COVID-19 pandemic and explore the impact and implications of lockdown on people with dementia and family carers. METHODS: This was a qualitative study that used semi-structured interviews to collect data from people with dementia and family carers. Interviews were conducted online via video call, individually or within caring dyads. Initially, data were coded, analysed and themed inductively. Additionally, social disruption and social division theories were used to deductively identify patterns in the data to enhance understanding. FINDINGS: Six distinct themes were identified from the inductive analysis: Routine: 'busy life before lockdown'; Isolation: 'four walls and a garden'; Living with restrictions: 'treading on eggshells'; Discovering positives: 'you are in the same boat'; Easing lockdown: 'raring to go'; Heightened uncertainty: 'things have changed'. Illustrative examples of symptoms of social disruption and division were identified within the data: frustration, democratic disconnection, fragmentation, polarisation and escalation. CONCLUSION: Experiences of people with dementia and family carers during the pandemic were mixed, resulting in hopes and worries for the future. Social disruption and social division are relevant frameworks for analysing experiences of COVID-19.

Developing country-specific questions about end-of-life care for nursing home residents with advanced dementia using the nominal group technique with family caregivers.

OBJECTIVE: We aimed to develop question prompt lists (QPLs) for family caregivers of nursing home residents with advanced dementia in the context of a study involving Canada, the Czech Republic, Italy, the Netherlands, the United Kingdom and Ireland, and to explore cross-national differences. QPLs can encourage family caregivers to ask questions about their relative's end-of-life care. METHODS: We used nominal group methods to create country-specific QPLs. Family caregivers read an information booklet about end-of-life care for people with dementia, and generated questions to ask healthcare professionals. They also selected questions from a shortlist. We analyzed and compared the QPLs using content analysis. RESULTS: Four to 20 family caregivers per country were involved. QPLs ranged from 15 to 24 questions. A quarter (24%) of the questions appeared in more than one country's QPL. One question was included in all QPLs: "Can you tell me more about palliative care in dementia?". CONCLUSION: Family caregivers have many questions about dementia palliative care, but the local context may influence which questions specifically. Local end-user input is thus important to customize QPLs. PRACTICE IMPLICATIONS: Prompts for family caregivers should attend to the unique information preferences among different countries. Further research is needed to evaluate the QPLs' use.

Palliative care in Creutzfeldt-Jakob disease: looking back, thinking ahead.

Creutzfeldt-Jakob disease (CJD) is a rare and fatal neurodegenerative disease for which there is no cure. However, it is difficult to diagnose and is unique in that it is both a genetic and transmissible disease. The disease is characterised by symptoms of a rapidly progressive dementia. Palliation is the only treatment and early diagnosis is an important aspect in relation to gaining speedy access to palliative and end-of-life care services. People with CJD may be cared for in a diversity of settings including; general hospital wards, neurological units, hospices; care homes and in their own home. Management of physical and psychosocial symptoms and dealing with family bereavement is complex and challenging. Due to the complexity of the physical symptoms input from clinicians with palliative care expertise is an important consideration. Given transmission risk and the latent incidence of infection in the general population, following the emergence of variant CJD; plus the recent hypothesis of a potential relationship between immune responses to COVID-19 and the acceleration of preclinical or evident neurodegenerative disease, there is a need for renewed interest in research in this field. Over the past 20 years, many thousands of articles have been published on CJD. These have been predominately in the medical and science literature and very few publications have addressed the nursing care of persons and families dealing with CJD. There is a need for renewed interest in the management of the disease by supportive and palliative care services.

Systematic analysis of SARS-CoV-2 infection of an ACE2-negative human airway cell.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) variants govern transmissibility, responsiveness to vaccination, and disease severity. In a screen for new models of SARS-CoV-2 infection, we identify human H522 lung adenocarcinoma cells as naturally permissive to SARS-CoV-2 infection despite complete absence of angiotensin-converting enzyme 2 (ACE2) expression. Remarkably, H522 infection requires the E484D S variant; viruses expressing wild-type S are not infectious. Anti-S monoclonal antibodies differentially neutralize SARS-CoV-2 E484D S in H522 cells as compared to ACE2-expressing cells. Sera from vaccinated individuals block this alternative entry mechanism, whereas convalescent sera are less effective. Although the H522 receptor remains unknown, depletion of surface heparan sulfates block H522 infection. Temporally resolved transcriptomic and proteomic profiling reveal alterations in cell cycle and the antiviral host cell response, including MDA5-dependent activation of type I interferon signaling. These findings establish an alternative SARS-CoV-2 host cell receptor for the E484D SARS-CoV-2 variant, which may impact tropism of SARS-CoV-2 and consequently human disease pathogenesis.

A Taxonomy of Arts Interventions for People With Dementia.

BACKGROUND AND OBJECTIVES: The current evidence base for the arts and dementia has several limitations relating to the description, explanation, communication, and simplification of arts interventions. Research addressing these challenges must be multidisciplinary, taking account of humanities and science perspectives. Consequently, this research aimed to produce a taxonomy, or classification, of arts interventions for people with dementia as a contribution to this growing field. RESEARCH DESIGN AND METHODS: This research was underpinned by taxonomy and realist methodology. Taxonomy, the science of classification, produces a common language to name, define, and describe the world around us. Realist theory explains how interventions "work" and produce their effects. The main findings in this paper were generated from a case study and a Delphi study. RESULTS: An arts and dementia taxonomy of 12 dimensions was developed: Art Form, Artistic elements, Artistic focus, Artistic materials, Arts activity, Arts approaches, Arts facilitators, Arts location, Competencies, Complementary arts, Intervention context, Principles. DISCUSSION AND IMPLICATIONS: Arts interventions can be classified according to their contexts, mechanisms, and outcomes. A range of stakeholders could benefit from the taxonomy, including people with dementia, artists, practitioners, carers, care staff, funders, commissioners, researchers, and academics. Language relating to the arts and dementia can be adapted depending on the audience. This is a foundational model requiring further development within the arts and dementia community.

PPP6C Negatively Regulates STING-Dependent Innate Immune Responses.

Stimulator of interferon genes (STING) is an essential adaptor protein of the innate DNA-sensing signaling pathway, which recognizes genomic DNA from invading pathogens to establish antiviral responses in host cells. STING activity is tightly regulated by several posttranslational modifications, including phosphorylation. However, specifically how the phosphorylation status of STING is modulated by kinases and phosphatases remains to be fully elucidated. In this study, we identified protein phosphatase 6 catalytic subunit (PPP6C) as a binding partner of Kaposi's sarcoma-associated herpesvirus (KSHV) open reading frame 48 (ORF48), which is a negative regulator of the cyclic GMP-AMP synthase (cGAS)-STING pathway. PPP6C depletion enhances double-stranded DNA (dsDNA)-induced and 5'ppp double-stranded RNA (dsRNA)-induced but not poly(I:C)-induced innate immune responses. PPP6C negatively regulates dsDNA-induced IRF3 activation but not NF-κB activation. Deficiency of PPP6C greatly inhibits the replication of herpes simplex virus 1 (HSV-1) and vesicular stomatitis virus (VSV) as well as the reactivation of KSHV, due to increased type I interferon production. We further demonstrated that PPP6C interacts with STING and that loss of PPP6C enhances STING phosphorylation. These data demonstrate the important role of PPP6C in regulating STING phosphorylation and activation, which provides an additional mechanism by which the host responds to viral infection.IMPORTANCE Cytosolic DNA, which usually comes from invading microbes, is a dangerous signal to the host. The cGAS-STING pathway is the major player that detects cytosolic DNA and then evokes the innate immune response. As an adaptor protein, STING plays a central role in controlling activation of the cGAS-STING pathway. Although transient activation of STING is essential to trigger the host defense during pathogen invasion, chronic STING activation has been shown to be associated with several autoinflammatory diseases. Here, we report that PPP6C negatively regulates the cGAS-STING pathway by removing STING phosphorylation, which is required for its activation. Dephosphorylation of STING by PPP6C helps prevent the sustained production of STING-dependent cytokines, which would otherwise lead to severe autoimmune disorders. This work provides additional mechanisms on the regulation of STING activity and might facilitate the development of novel therapeutics designed to prevent a variety of autoinflammatory disorders.

Principles and features to define and describe arts interventions for people with dementia: a qualitative realist study.

Background: There is currently no consensus regarding the definition and description of arts interventions for people with dementia. Developing a common language of classification will encourage reflection on artistic practice, support the evaluation and improvement of arts interventions, and enable their benefits to be communicated more effectively. Methods: Using a qualitative framework derived from taxonomy and realist methodology, a literature review was undertaken to identify what key principles underpin arts interventions. This analysis was complemented by focus groups and workshops incorporating the lived experience of carers, artists, practitioners and care staff. Results: Nine principles were identified as elements present in person-centred arts interventions for people with dementia: Animation, Transcendence, Selfhood, Humanity, Expression, Connection, Possibility, Involvement and Awareness. Conclusions: It is possible to identify the component parts of arts interventions for people with dementia. These principles form an empirical basis for understanding how arts interventions work, while still respecting their individual nature.

Competitive Kinase Enrichment Proteomics Reveals that Abemaciclib Inhibits GSK3ß and Activates WNT Signaling.

The cellular and organismal phenotypic response to a small-molecule kinase inhibitor is defined collectively by the inhibitor's targets and their functions. The selectivity of small-molecule kinase inhibitors is commonly determined in vitro, using purified kinases and substrates. Recently, competitive chemical proteomics has emerged as a complementary, unbiased, cell-based methodology to define the target landscape of kinase inhibitors. Here, we evaluated and optimized a competitive multiplexed inhibitor bead mass spectrometry (MIB/MS) platform using cell lysates, live cells, and treated mice. Several clinically active kinase inhibitors were profiled, including trametinib, BMS-777607, dasatinib, abemaciclib, and palbociclib. MIB/MS competition analyses of the cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors abemaciclib and palbociclib revealed overlapping and unique kinase targets. Competitive MIB/MS analysis of abemaciclib revealed 83 target kinases, and dose-response MIB/MS profiling revealed glycogen synthase kinase 3 alpha and beta (GSK3α and ß) and Ca2+/calmodulin-dependent protein kinase II delta and gamma (CAMKIIδ and γ) as the most potently inhibited. Cell-based and in vitro kinase assays show that in contrast to palbociclib, abemaciclib directly inhibits GSK3α/ß and CAMKIIγ/δ kinase activity at low nanomolar concentrations. GSK3ß phosphorylates ß-catenin to suppress WNT signaling, while abemaciclib (but not palbociclib or ribociclib) potently activates ß-catenin-dependent WNT signaling. These data illustrate the power of competitive chemical proteomics to define kinase target specificities for kinase inhibitors, thus informing clinical efficacy, dose-limiting toxicities, and drug-repurposing efforts.Implications: This study uses a rapid and quantitative proteomics approach to define inhibitor-target data for commonly administered therapeutics and provides a cell-based alternative to in vitro kinome profiling. Mol Cancer Res; 16(2); 333-44. ©2017 AACR.

Ponatinib Shows Potent Antitumor Activity in Small Cell Carcinoma of the Ovary Hypercalcemic Type (SCCOHT) through Multikinase Inhibition.

Purpose: Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is a rare, aggressive ovarian cancer in young women that is universally driven by loss of the SWI/SNF ATPase subunits SMARCA4 and SMARCA2. A great need exists for effective targeted therapies for SCCOHT.Experimental Design: To identify underlying therapeutic vulnerabilities in SCCOHT, we conducted high-throughput siRNA and drug screens. Complementary proteomics approaches profiled kinases inhibited by ponatinib. Ponatinib was tested for efficacy in two patient-derived xenograft (PDX) models and one cell-line xenograft model of SCCOHT.Results: The receptor tyrosine kinase (RTK) family was enriched in siRNA screen hits, with FGFRs and PDGFRs being overlapping hits between drug and siRNA screens. Of multiple potent drug classes in SCCOHT cell lines, RTK inhibitors were only one of two classes with selectivity in SCCOHT relative to three SWI/SNF wild-type ovarian cancer cell lines. We further identified ponatinib as the most effective clinically approved RTK inhibitor. Reexpression of SMARCA4 was shown to confer a 1.7-fold increase in resistance to ponatinib. Subsequent proteomic assessment of ponatinib target modulation in SCCOHT cell models confirmed inhibition of nine known ponatinib target kinases alongside 77 noncanonical ponatinib targets in SCCOHT. Finally, ponatinib delayed tumor doubling time 4-fold in SCCOHT-1 xenografts while reducing final tumor volumes in SCCOHT PDX models by 58.6% and 42.5%.Conclusions: Ponatinib is an effective agent for SMARCA4-mutant SCCOHT in both in vitro and in vivo preclinical models through its inhibition of multiple kinases. Clinical investigation of this FDA-approved oncology drug in SCCOHT is warranted. Clin Cancer Res; 24(8); 1932-43. ©2018 AACR.