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Background Numerous case reports and case series have described brain Magnetic Resonance Imaging (MRI) findings in Coronavirus disease 2019 (COVID-19) patients with concurrent posterior reversible encephalopathy syndrome (PRES). Purpose We aim to compile and analyze brain MRI findings in patients with COVID-19 disease and PRES. Methods PubMed and Embase were searched on April 5th, 2021 using the terms “COVID-19”, “PRES”, “SARS-CoV-2” for peer-reviewed publications describing brain MRI findings in patients 21 years of age or older with evidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and PRES. Results Twenty manuscripts were included in the analysis, which included descriptions of 30 patients. The average age was 57 years old. Twenty-four patients (80%) required mechanical ventilation. On brain MRI examinations, 15 (50%) and 7 (23%) of patients exhibited superimposed foci of hemorrhage and restricted diffusion respectively. Conclusions PRES is a potential neurological complication of COVID-19 related disease. COVID-19 patients with PRES may exhibit similar to mildly greater rates of superimposed hemorrhage compared to non-COVID-19 PRES patients.

The coronavirus disease 2019 (COVID -19) pandemic caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected almost every country in the world, resulting in severe morbidity, mortality and economic hardship, and altering the landscape of healthcare forever. Although primarily a pulmonary illness, it can affect multiple organ systems throughout the body, sometimes with devastating complications and long-term sequelae. As we move into the second year of this pandemic, a better understanding of the pathophysiology of the virus and the varied imaging findings of COVID-19 in the involved organs is crucial to better manage this complex multi-organ disease and to help improve overall survival. This manuscript provides a comprehensive overview of the pathophysiology of the virus along with a detailed and systematic imaging review of the extra-thoracic manifestation of COVID-19 with the exception of unique cardiothoracic features associated with multisystem inflammatory syndrome in children (MIS-C). In Part I, extra-thoracic manifestations of COVID-19 in the abdomen in adults and features of MIS-C will be reviewed. In Part II, manifestations of COVID-19 in the musculoskeletal, central nervous and vascular systems will be reviewed.

Disasters are a primary influence in the global development landscape given their unequal impacts across society and calls for transformative change in their aftermath. Recovering from disasters is one component of development that is coming under scrutiny. This is especially so in the context of the COVID-19 pandemic, whose scale, scope, and cascading effects mean that the uncertain prospects for recovery will be complicated and endure long term. COVID-19 has forced a reappraisal of what recovery encompasses, who it is for, and how it can better enable preparedness for future disasters. Drawing upon interviews with a global community of experts specializing in different areas of disaster governance, this paper focuses on the lessons emerging for recovery-related theory and practice deriving from the pandemic. We elaborate a multi-dimensional framework to support those working on local recovery planning within communities and operating across different sectors. The framework captures the interconnected issues across six principal domains—communities, economic, infrastructure, environment, health, and governance—representing key impact areas around which strategies and multifaceted actions can be developed. We suggest a three-step process using a systems approach to develop a recovery strategy that operationalizes the framework and addresses the complexity of long-term recovery for development.

BackgroundResilience is a ubiquitous but often misunderstood term. It is often studied and described within the lens of individual academic disciplines, despite the complexities and interactions of today’s world. Using a meta-narrative approach, we performed a systematic literature review of healthcare resilience, tracking the research traditions which have informed this field. This paper consolidates knowledge about the definitions, measures, and concepts of healthcare resilience at meso- and macro-levels, to build an interdisciplinary, cross-sectoral, and multi-level (ICM) approach and framework. It forms part of a wider project on healthcare resilience, within a larger research group on societal resilience and guides efforts to build resilience after the COVID19 pandemic.MethodsForty-five reviews were analysed thematically, adhering to RAMESES and PRISMA guidelines. We explore issues inherent to fundamental terms and propose a unified definition spanning event timescales and applicable to multiple hierarchical levels. Studies tended to focus on individual hierarchical levels using a range of frameworks, which are frequently also used as measurement indices. Macro-level indices focusing on capacities failed to sufficiently capture the importance of relational aspects of systems resilience. Meso-level approaches and frameworks tended to swing between the extremes of disaster risk reduction strategies and patient safety approaches for normal stressors. Micro-level approaches were not a focus but tended to centre around acute psychological interventions.ResultsThe analysis allowed us to propose a unified definition and build an overall framework for healthcare resilience containing pre-, intra-, post-, and trans-event domains, which work across hierarchical levels. We also adopt a realist view by presenting a table of selected resilience frameworks, categorising them according to predominant hierarchical level and timescale. This aims to guide decision-makers about the suitability of various frameworks, at specific levels, through numerous points during crises. ConclusionThere is increasing acknowledgement of the need for inter-disciplinary, cross-sectoral, and multi-level approaches to healthcare resilience, but such work is hitherto rare. A realist approach to various resilience frameworks may help to determine best-fit for individual organisations and systems. There is a need to better understand how resilience practically works across various hierarchical levels.

The coronavirus disease 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected almost every country in the world resulting in severe morbidity, mortality and economic hardship, altering the landscape of healthcare forever. Its devastating and most frequent thoracic and cardiac manifestations have been well reported since the start of the pandemic. Its extra-thoracic manifestations are myriad and understanding them is critical in diagnosis and disease management. The role of radiology is growing in the second wave and second year of the pandemic as the multiorgan manifestations of COVID-19 continue to unfold. Musculoskeletal, neurologic and vascular disease processes account for a significant number of COVID-19 complications and understanding their frequency, clinical sequelae and imaging manifestations is vital in guiding management and improving overall survival. The authors aim to provide a comprehensive overview of the pathophysiology of the virus along with a detailed and systematic imaging review of the extra-thoracic manifestation of COVID-19. In Part I, abdominal manifestations of COVID-19 in adults and multisystem inflammatory syndrome in children will be reviewed. In Part II, manifestations of COVID-19 in the musculoskeletal, central nervous and vascular systems will be reviewed.

ObjectiveSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is protean in its manifestations, affecting nearly every organ system. However, nervous system involvement and its effect on disease outcome are poorly characterized. The objective of this study was to determine whether neurologic syndromes are associated with increased risk of inpatient mortality.MethodsA total of 581 hospitalized patients with confirmed SARS-CoV-2 infection, neurologic involvement, and brain imaging were compared to hospitalized non-neurologic patients with coronavirus disease 2019 (COVID-19). Four patterns of neurologic manifestations were identified: acute stroke, new or recrudescent seizures, altered mentation with normal imaging, and neuro-COVID-19 complex. Factors present on admission were analyzed as potential predictors of in-hospital mortality, including sociodemographic variables, preexisting comorbidities, vital signs, laboratory values, and pattern of neurologic manifestations. Significant predictors were incorporated into a disease severity score. Patients with neurologic manifestations were matched with patients of the same age and disease severity to assess the risk of death.ResultsA total of 4,711 patients with confirmed SARS-CoV-2 infection were admitted to one medical system in New York City during a 6-week period. Of these, 581 (12%) had neurologic issues of sufficient concern to warrant neuroimaging. These patients were compared to 1,743 non-neurologic patients with COVID-19 matched for age and disease severity admitted during the same period. Patients with altered mentation (n = 258, p = 0.04, odds ratio [OR] 1.39, confidence interval [CI] 1.04–1.86) or radiologically confirmed stroke (n = 55, p = 0.001, OR 3.1, CI 1.65–5.92) had a higher risk of mortality than age- and severity-matched controls.ConclusionsThe incidence of altered mentation or stroke on admission predicts a modest but significantly higher risk of in-hospital mortality independent of disease severity. While other biomarker factors also predict mortality, measures to identify and treat such patients may be important in reducing overall mortality of COVID-19.

Assess the prevalence of white matter microstructural changes in combat veterans, within the context of a highly matched control group comprising unexposed close relatives. This prospective study had institutional review board approval, included written informed consent, and is HIPAA-compliant. Diffusion tensor imaging was analyzed in 16 male blast-exposed combat veterans of Operation Iraqi Freedom/Operation Enduring Freedom (mean age 31.0 years) and 18 unexposed males (mean age 30.4 years) chosen on the basis of a consanguineous relationship to a member of the subject group. Whole-brain voxel-based comparison of fractional anisotropy (FA) was performed using both group and individual analyses. Areas where effects on FA were detected were subsequently characterized by extracting radial diffusivity (RD), axial diffusivity (AD), and mean diffusivity (MD) from the regions of abnormal FA. Controls did not differ from veterans on any background demographic factor. In voxel-based group comparison, we identify high fractional anisotropy (FA) in veterans compared to controls (p

The cathedral city of Armagh is one of the most historically and architecturally significant on the island of Ireland. This article explores the preparation of an inventory of Armagh’s architectural heritage by the London architect-planner Max Lock in 1964, commissioned by the Northern Ireland Committee of the National Trust. The inventory represents one aspect of the initial response of civil society to impending change in the built environment in the mid-1960s and formed part of efforts to ensure parity with Great Britain in land-use planning legislation. The inventory facilitates a wider discussion on state-civil society relations in Northern Ireland, the values and ideas guiding change within historic settlements, and the place promotional advantage that the local council sought to derive from Armagh’s history and heritage. Utilizing Ward’s typology of diffusion, it is argued that Northern Ireland represents an unusual ‘within-UK’ example of the transference of planning ideas and practices, with its historical experience of devolution offering valuable contemporary insights into the increasingly diffuse and fragmented governance space within the UK.

Terence O’Neill maintained a keen interest in conservation and architectural heritage, but his record on these issues in government in Northern Ireland is largely unexamined. This article addresses this deficit through a comprehensive review of the existing literature reinforced by archival material, revealing the familial and other connections that O’Neill had with the conservation world and civil society organisations, including his sometimes behind-the-scenes interventions on conservation policy. The momentous impact on the existing built environment from his drive to ‘transform the face of Ulster’ is ultimately foregrounded, particularly the contemporary philosophy underpinning the ‘balanced approach’ to development that was initially favoured by progressive opinion in the early 1960s, and the effect that the destruction of familiar places had on the creation of new heritage values. However, the failure of O’Neill to introduce town and country planning legalisation akin to that existing in Great Britain frustrated the efforts of conservationists who grew increasingly vociferous in their calls for action. As in other contested areas of public policy in the 1960s in Northern Ireland, the destructive forces unleashed in the built environment threatened architectural heritage and essentially remained unchecked in the absence of timely reforms prior to Direct Rule from Westminster.

This article describes a maximum likelihood method for estimating the parameters of the standard square-root stochastic volatility model and a variant of the model that includes jumps in equity prices. The model is fitted to data on the S&P 500 Index and the prices of vanilla options written on the index, for the period 1990 to 2011. The method is able to estimate both the parameters of the physical measure (associated with the index) and the parameters of the risk-neutral measure (associated with the options), including the volatility and jump risk premia. The estimation is implemented using a particle filter whose efficacy is demonstrated under simulation. The computational load of this estimation method, which previously has been prohibitive, is managed by the effective use of parallel computing using graphics processing units (GPUs). The empirical results indicate that the parameters of the models are reliably estimated and consistent with values reported in previous work. In particular, both the vola...

This article explores the creation of the system for the conservation of architectural heritage in Northern Ireland, evidencing the struggle for convergence within the UK before 1972. The agency of networked individuals, close state–civil society interrelationships and the innovative actions of conservationist groups in response to legislative and practice inadequacies in the 1960s are discussed. In particular, a series of ‘pre-statutory lists’ are introduced, highlighting the burgeoning interest in industrial archaeology and Victorian architecture in Belfast and the prompt provided to their creation by redevelopment. The efforts of conservationists were eventually successful after the collapse of Devolution in the early 1970s.

On 9 August 1945, the United States dropped an atomic bomb on Nagasaki. Of the dead, approximately 8500 were Catholic, representing sixty to seventy-five percent of their own community and over ten percent of the total. This thesis analyses the memories and narratives of surviving members of the Catholic community in Nagasaki through the lens of Johann Metz’s theology of ‘dangerous memory’. For the Catholic survivors, memories of the bombing destruction are linked to community narratives about religious persecution and marginalisation in earlier times. The survivors speak about ongoing tests of faith, but also their own resilience and survival.

Background: Oestrogen receptor positive (ER+) breast cancer patients can acquire endocrine resistance and 10-20% tumours have lost ER at relapse. While growth factor pathway hyperactivity and ER promoter methylation contribute to de novo ER negativity, ER loss in acquired resistance is largely unexplored. We have recently developed 11 lines from MCF7, T47D, BT474 & MDAMB361 cells to model acquired resistance emerging with prolonged (3 year) endocrine treatment both in ER+/HER2- and ER+/HER2+ disease. Here we establish prevalence of acquired ER loss in the panel, determine any association with aggressiveness, and explore ER loss mechanisms in acquired endocrine resistance. Methods: Authenticated acquired resistant models derived from endocrine responsive lines cultured for 3 years with 10-7M tamoxifen (TamR), 10-7M fulvestrant (FasR) or oestrogen deprivation (5% charcoal-stripped foetal calf serum SFCSR) were profiled for ER & PR by PCR, immunocytochemistry and Western blotting (+/- 1-2wk antihormone withdrawal), for 2nd-line endocrine responsiveness and for migration using Boyden chamber assays vs. time-matched controls. Src kinase, EGFR, HER2, MAPK & AKT activity were examined and whether their respective inhibition using saracatinib or gefitinib (1μM), trastuzumab (100nM), U0126 or LY294002 (5μM) for 1wk restored ER. ESR1 promoter methylation was examined by bisulfite modification & MethyLight PCR. Results: Substantial ER mRNA & protein loss occurred in 7/11 long-term acquired endocrine resistant lines. This was irreversible by antihormone withdrawal and paralleled by complete PR loss and endocrine growth-insensitivity. While seen in all fulvestrant resistant lines, ER loss was less frequent with tamoxifen (in MCF7TamR & MDATamR) and only seen in oestrogen deprived resistant T47DSFCSR cells. Increased migration accompanied acquired ER loss in ER+/HER2- derived MCF7TamR, MCF7FasR & T47DSFCSR cells and was saracatinib-sensitive. Src and further growth factor pathway activity increased in several acquired resistant models, and ER loss associated with increased EGFR/HER2 in the MCF7- & MDA-derived cells and with increased MAPK activity in all lines. Weak ER recovery was seen in antioestrogen resistant models treated with saracatinib (MDATamR, MCF7FasR), gefitinib (MDATamR, BT474FasR, MCF7FasR/TamR) or trastuzumab (MCF7TamR). ESR1 DNA methylation was only prominent in MDATamR and MCF7TamR cells. No inhibitor restored ER in the T47D-derived cells, including T47DSFCSR which also lacked ESR1 methylation. Conclusions: Although ER loss is very prominent in this acquired resistant cell panel, it demonstrates there is capacity of prolonged antihormones, chiefly antioestrogens, to promote receptor loss independent of initial HER2 status. Acquired ER loss clinically would be expected to confer endocrine insensitivity and poorer prognosis given the panel findings. Where ER loss emerged with antioestrogens there was some mechanistic-overlap with de novo ER negativity, including ER promoter methylation for acquired tamoxifen resistance. Our future studies will use the panel to address if targeting these mechanisms can be optimized for ER recovery or if further mechanisms also drive ER loss in acquired resistance, notably for prolonged oestrogen deprivation. Citation Format: Julia M Gee, Mei Yee Meng, Richard A McClelland, Huw J Mottram, Susan R Kyme, Pauline Finlay, Lindy Goddard, Carol M Dutkowski, Denise Barrow, Walther Parson, Heidi Fiegl. A new cell panel to study oestrogen receptor loss in acquired endocrine resistant breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-05-19.

This paper investigates several competing procedures for computing the prices of vanilla European options, such as puts, calls and binaries, in which the underlying model has a characteristic function that is known in semi-closed form. The algorithms investigated here are the half-range Fourier cosine series, the half-range Fourier sine series and the full-range Fourier series. Their performance is assessed in simulation experiments in which an analytical solution is available and also for a simple affine model of stochastic volatility in which there is no closed-form solution. The results suggest that the half-range sine series approximation is the least effective of the three proposed algorithms. It is rather more difficult to distinguish between the performance of the half-range cosine series and the full-range Fourier series. However there are two clear differences. First, when the interval over which the density is approximated is relatively large, the full-range Fourier series is at least as good as the half-range Fourier cosine series, and outperforms the latter in pricing out-of-the-money call options, in particular with maturities of three months or less. Second, the computational time required by the half-range Fourier cosine series is uniformly longer than that required by the full-range Fourier series for an interval of fixed length. Taken together, these two conclusions make a case for pricing options using a full-range range Fourier series as opposed to a half-range Fourier cosine series if a large number of options are to be priced in as short a time as possible.

Values and a values-based approach to management and decision-making processes over cultural heritage are explored and critically reviewed. It is argued that a broader range of values, particularly those emanating from the ‘dark side’, should be accommodated into future values-based theory and practice if decisions are to be more comprehensive and transparent. The paper underlines the necessity for those working with cultural heritage, including within the arena of statutory land-use planning, to engage more deeply with cross-disciplinary and international perspectives on heritage values.

A quasi-maximum likelihood procedure for estimating the parameters of multi-dimensional diffusions is developed in which the transitional density is a multivariate Gaussian density with first and second moments approximating the true moments of the unknown density. For affine drift and diffusion functions, the moments are exactly those of the true transitional density and for nonlinear drift and diffusion functions the approximation is extremely good and is as effective as alternative methods based on likelihood approximations. The estimation procedure generalises to models with latent factors. A conditioning procedure is developed that allows parameter estimation in the absence of proxies.

The tetrahydroazepinone pharmacophore is a component of many interesting compounds, including several marine natural products, with anti-cancer properties. The synthesis and biological evaluation of a novel series of pyrroloazepinone and indoloazepinone oximes is reported. These compounds showed promising growth inhibition activity against four human cancer cell lines but did not significantly inhibit the cell cycle regulator cyclin dependent kinase 2. The most active compounds in this series displayed improved anti-proliferative activity over the related synthetic indoloazepine kenpaullone. The structure activity relationships exhibited by the azepinone pharmacophore suggests several novel lead compounds for anti-cancer drug discovery.

Much research has investigated the differences between option implied volatilities and econometric model-based forecasts. Implied volatility is a market determined forecast, in contrast to model-based forecasts that employ some degree of smoothing of past volatility to generate forecasts. Implied volatility has the potential to reflect information that a model-based forecast could not. This paper considers two issues relating to the informational content of the S&P 500 VIX implied volatility index. First, whether it subsumes information on how historical jump activity contributed to the price volatility, followed by whether the VIX reflects any incremental information pertaining to future jump activity relative to model-based forecasts. It is found that the VIX index both subsumes information relating to past jump contributions to total volatility and reflects incremental information pertaining to future jump activity. This issue has not been examined previously and expands our understanding of how option markets form their volatility forecasts.

The multiple socio-economic benefits ascribed to cycling are increasingly recognised by politicians and policymakers on the island of Ireland. Although a network of greenways and long-distance cycle routes are under construction in many urban and rural areas, harnessing the numerous opportunities in the Irish border region remains under-developed. To progress the development of cycling infrastructure in the border region, it is asserted that local and national policy frameworks require strengthening and integration; that strategic coordination and master-planning processes should be initiated; and, innovative funding mechanisms are needed to enable on-the-ground delivery. Improved cross-border connectivity is considered a critical component in realising the promised ‘cycling revolution’ on the island.

The potent inhibitory activity of novel 2-benzyltetralone and 2-benzylidenetetralone derivatives vs liver microsomal retinoic acid metabolizing enzymes and a MCF-7 CYP26A1 cell assay is described. In the liver microsomal assay, the 2-biphenylmethyl-6-hydroxytetralone derivatives 16a and 16b were found to be potent inhibitors (IC50 = 0.5 and 0.8 microM) compared with the broad spectrum P450 inhibitor ketoconazole and the retinoid mimetic R115866 (IC50 = 18.0 and 9.0 microM, respectively). In the MCF-7 CYP26A1 cell assay, the 2-(4-hydroxybenzyl)-6-methoxytetralone 5 and unsaturated benzylidene precursor 6 were found to be the most potent (IC50 = 7 and 5 microM, respectively), which was comparable with liarozole (7 microM) but considerably less active than R115866 (IC50 = 5 nM). With a CYP26A1 homology model, the tetralones were shown to be positioned in a hydrophobic tunnel with additional interactions, e.g., transition metal coordination and hydrogen-bonding interactions with GLY300, observed for the potent 4-hydroxyphenyl substituted inhibitors.

Although many estrogen receptor-positive breast cancers initially respond to antihormones, responses are commonly incomplete with resistance ultimately emerging. Delineation of signaling mechanisms underlying these phenomena would allow development of therapies to improve antihormone response and compromise resistance. This in vitro investigation in MCF-7 breast cancer cells examines whether epidermal growth factor receptor (EGFR) signaling limits antiproliferative and proapoptotic activity of antihormones and ultimately supports development of resistance. It addresses whether the anti-EGFR agent gefitinib (ZD1839/Iressa; TKI: 1 mum) combined with the antihormones 4-hydroxytamoxifen (TAM: 0.1 mum) or fulvestrant (Faslodex; 0.1 mum) enhances growth inhibition and prevents resistance. TAM significantly suppressed MCF-7 growth over wk 2-5, reducing proliferation detected by immunocytochemistry and fluorescence-activated cell sorter cell cycle analysis. A modest apoptotic increase was observed by fluorescence-activated cell sorter and fluorescence microscopy, with incomplete bcl-2 suppression. EGFR induction occurred during TAM response, as measured by immunocytochemistry and Western blotting, with EGFR-positive, highly proliferative resistant growth subsequently emerging. Although TKI alone was ineffective on growth, TAM plus TKI cotreatment exhibited superior antigrowth activity vs. TAM, with no viable cells by wk 12. Cotreatment was more effective in inhibiting proliferation, promoting apoptosis, and eliminating bcl-2. Cotreatment blocked EGFR induction, markedly depleted ERK1/2 MAPK and protein kinase B phosphorylation, and prevented emergence of EGFR-positive resistance. Faslodex plus TKI cotreatment was also a superior antitumor strategy. Thus, increased EGFR evolves during treatment with antihormones, limiting their efficacy and promoting resistance. Gefitinib addition to antihormonal therapy could prove more effective in treating estrogen receptor-positive breast cancer and may combat development of resistance.

There is an increasing body of evidence demonstrating that growth factor networks are highly interactive with oestrogen receptor (ER) signalling in the control of breast cancer growth. As such, tumour responses to anti- hormones are likely to be a composite of the ER and growth factor inhibitory activity of these agents. The current article examines the modulation of growth factor networks during endocrine response, and presents in vitro and clinical evidence that epidermal growth factor receptor signalling, maintained in either an ER-dependent or -independent manner, is critical to anti- hormonal-resistant breast cancer cell growth. The considerable potential of the epidermal growth factor receptor-selective tyrosine kinase inhibitor, ZD 1839 (Iressa; AstraZeneca) to efficiently treat, and perhaps even prevent, endocrine-resistant breast cancer is highlighted.

An immunocytochemical assay for the p53-regulated protein product of the WAF1/Cip1 gene, p21WAF1 (p21), was developed and applied to archival primary breast tumour material from 91 patients whose subsequent recurrent disease was treated with assessable courses of endocrine therapy. Nuclear localization of p21 protein was observed in 76 (82·4 per cent) cases. Status cut-offs were established and 29 (31·9 per cent) were deemed negative, 39 (42·9 per cent) weakly positive, and 23 (25·3 per cent) strongly positive. p21 status was inversely correlated with p53 protein (p = 0·047) but did not relate to oestrogen receptor (ER) status, response to endocrine therapy, or time to further disease progression (TTP). Highly p21-positive patients had a significantly improved overall survival time (p = 0·020). Co-assessment of p21 and p53 subgroups revealed p21 + /p53 − patients to have good survival characteristics, whilst p21 − /p53+ patients did poorly (p = 0·008). The p21 − /p53− patients overall did intermediately well, but Ki67-defined cellular proliferation analysis of these revealed two subclasses: those with high proliferation and poor survival times resembling the p21 − /p53+ phenotype, and those with less proliferative tumours with good survival, similar to the p21 + /p53− group. The significance of these results is discussed in the light of recent research concerning the role of p21 and p53 in breast cancer aetiology.

The EMS1 and CCND1 genes at chromosome 11q13 are amplified in about 15% of primary breast cancers but appear to confer different phenotypes in ER positive and ER negative tumours. Since there are no published data on EMS1 expression in large series of breast cancers we examined the relationship of EMS1 expression with EMS1 gene copy number and expression of mRNAs for cyclin D1 and ER. In a subset of 129 patients, where matched tumour RNA and DNA was available, EMS1 mRNA overexpression was associated predominantly with gene amplification (P = 0.0061), whereas cyclin D1 mRNA overexpression was not (P = 0.3142). In a more extensive series of 351 breast cancers, there was no correlation between cyclin D1 and EMS1 expression in the EMS1 and cyclin D1 overexpressors (P = 0.3503). Although an association between EMS1 mRNA expression and ER positivity was evident (P = 0.0232), when the samples were divided into quartiles of EMS1 or cyclin D1 mRNA expression, the increase in the proportion of ER positive tumours in the ascending EMS1 mRNA quartiles was not statistically significant (P = 0.0951). In marked contrast there was a significant stepwise increase in ER positivity in ascending quartiles of cyclin D1 mRNA (P = 0.030). A potential explanation for this difference was provided by the observation that in ER positive breast cancer cells oestradiol treatment resulted in increased cyclin D1 gene expression but was without effect on EMS1. The relationship between EMS1 expression and clinical outcome was examined in a subset of 234 patients with median follow-up of 74 months. High EMS1 expression was associated with age > 50 years (P = 0.0001), postmenopausal status (P = 0.0008), lymph node negativity (P = 0.019) and an apparent trend for worse prognosis in the ER negative subgroup. These data demonstrate that overexpression of EMS1 mRNA is largely due to EMS1 gene amplification, is independent of cyclin D1 and ER expression and, in contrast to cyclin D1, is not regulated by oestrogen. Independent overexpression of these genes may confer different phenotypes and disease outcomes in breast cancer as has been inferred from recent studies of EMS1 and CCND1 gene amplification.

The HER2 transmembrane receptor is a well-characterised predictive marker for trastuzumab benefit and may be associated with decreased benefit from endocrine therapy use. Despite the clinical effectiveness of anti-HER2 agents in such cases, resistance represents a significant limiting factor. Focal adhesion kinase (FAK) plays an important role in HER2 signalling, mediating downstream Akt activation in addition to HER2 cross talk with other growth factor receptors. In this study, we investigated the therapeutic potential of FAK in oestrogen receptor-positive (ER+)/HER2+ breast cancer using the novel FAK-specific inhibitor PF4554878 (‘PF878’). The activation of the FAK/HER2 signalling pathway was assessed in ER+/HER2− (MCF7 and T47D) and ER+/HER2+ (BT-474 and MDAMB361) breast cancer cells in the presence or absence of PF878 and PF878±trastuzumab. The effects of PF878 on cell growth as a monotherapy and in combination with trastuzumab were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Coulter counting with isobologram analysis to determine synergy/additive effects. FAK activation (at Y861 but not at Y397) was highest in ER+/HER2+ cells, which also demonstrated the greatest sensitivity to PF878. As a monotherapy, PF878 prevented heregulin-induced MDA361 cell migration, but had no significant effect on cell growth. The treatment of ER+/HER2+ cells with PF878 and trastuzumab in combination resulted in the synergistic inhibition of cell proliferation. Underlying this was an abrogation of Akt activity and increased poly(ADP-ribose) polymerase cleavage, effects that were greatest in trastuzumab-refractory MDA361 cells. Collectively, these data support a role for FAK in ER+/HER2+ breast cancer, where its targeting has the potential to improve trastuzumab response. This is particularly important in the context of ER+/HER2+, trastuzumab-refractory disease, where FAK inhibition may present an important strategy to restore trastuzumab sensitivity.

Effects of the pure antiestrogen ICI182780 and tamoxifen on ER-protein, ER-mRNA, and estrogen-regulated mRNA expression were analysed using matched pretreatment core-cut biopsies and post-treatment mastectomy samples from 43 ER positive human breast cancers. Sixteen controls received either no preoperative treatment (n = 9) (7 days) or placebo (n = 7) (median 21 days) prior to primary surgery. Nineteen patients received ICI182780 6 mg/day (n = 10) or 18 mg/day (n = 9) for 7 days. Eight patients were given preoperative tamoxifen (4 x 40 mg-day 1, 20 mg/day thereafter, median 21 days). ER-protein expression was assessed on pre and post treatment samples by immunocytochemistry. ER, pS2, pLIV1, and actin-mRNA expression was determined by northern analysis on post-treatment samples only. ER-mRNA levels were similar to controls following ICI182780 or tamoxifen treatment. However ER-protein levels were significantly suppressed by ICI182780, particularly at the higher dosage (p = 0.0013). Tamoxifen had no significant effect on ER-protein levels. The ER-mRNA and ER-protein contents of control tumors were linearly related (Spearman r = 0.719, p = 0.006). A similar relationship between pretreatment protein and post ICI182780 treatment mRNA levels was observed (r = 0.652, p = 0.005). However, comparison of post ICI182780 treatment protein and mRNA results shows a loss of linearity through a reduction in protein without concurrent loss of mRNA (r = 0.28, p = 0.257). pS2 mRNA hybridization was lower in ICI182780 treated samples than controls (Mann-Whitney p = 0.035) but was unaffected by tamoxifen. pLIV1 mRNA hybridization was uninfluenced by either treatment. Short term exposure of breast tumors to ICI182780 appears to produce a greater inhibition of estrogen-induced transcriptional events than tamoxifen. These effects appear to occur without a concurrent reduction in ER mRNA levels.

This paper investigates several competing procedures for computing the price of European and digital options in which the underlying model has a characteristic function that is known in at least semi-closed form. The algorithms for pricing the options investigated here are the half-range Fourier cosine series, the half-range Fourier sine series and the full-range Fourier series. The performance of the algorithms is assessed in simulation experiments which price options in a Black-Scholes world where an analytical solution is available and for a simple affine model of stochastic volatility in which there is no closed-form solution. The results suggest that the half-range sine series approximation is the least effective of the three proposed algorithms. It is rather more difficult to distinguish between the performance of the half-range cosine series and the full-range Fourier series. There are however two clear differences. First, when the interval over which the density is approximated is relatively large, the full-range Fourier series is at least as good as the half-range Fourier cosine series, and outperforms the latter in pricing out-of-the-money call options, in particular with maturities of three months or less. Second, the computational time required by the half-range Fourier cosine series is uniformly longer than that required by the full-range Fourier series for an interval of fixed length. Taken together, these two conclusions make a strong case for the merit of pricing options using a full-range range Fourier series as opposed to a half-range Fourier cosine series.

Immunocytochemical studies examining the Ki-67 proliferation marker in paraffin-embedded material have recently been made possible by the availability of several antibodies, notably MIB-1, which are readily applicable to microwaved sections. Using breast cancer material, the present study examines correlations shown by these new paraffin assays and also by PCNA (proliferating cell nuclear antigen), an existing marker of proliferation, with the established Ki-67 cryosection assay. Paraffin sections were microwaved prior to incubation with Ki-67 or MIB-1 antibodies. Signal detection was carried out with a biotinylated secondary antibody, peroxidase-conjugated streptavidin, and DAB/H2O2 chromogen. The results suggest that caution is required when studying proliferation in paraffin-embedded breast cancers by immunostaining using Ki-67 antibodies. Nuclear staining in wax sections (Ki-Par, MIB-1, PCNA) greatly exceeded that in cryosections (Ki-Froz) and thus correlations were notably absent between Ki-Par or PCNA immunostaining and the routine Ki-Froz assay. Immunostaining with MIB-1 or PCNA may, however, be useful to assess proliferation if cut-offs are applied to eliminate weak immunostaining associated with wax sections. Thus, an approximately linear relationship was seen between MIB-1/Ki-Froz, which was improved if only moderately or moderately/strongly MIB-1-positive cells were scored. Similarly, a significant correlation was also revealed between PCNA/Ki-Froz if such a cut-off was applied.

The protein product of the bcl-2 gene is thought to be involved in inhibition of apoptosis; it may therefore be important in the modulation of hormonal/anti-hormonal responsiveness exhibited by tumours. This study immunocytochemically investigates (i) relationships between bcl-2 protein expression in primary breast cancers and other markers of prognostic and therapeutic value and (ii) associations of the bcl-2 protein with breast cancer responsiveness to endocrine therapy. The bcl-2 protein was found within the tumour epithelial cell cytoplasm of 32/46 breast cancer specimens; inter-patient staining was heterogeneous. Immunostaining for steroid hormone receptors was strongly associated with that for the bcl-2 protein, and it is thus possible that this protein, like progesterone receptor, is under oestrogen regulation via oestrogen receptor. The protein was inversely related to 2 markers of endocrine insensitivity, epidermal growth factor receptor (EGFR) and c-erbB-2 oncoprotein, while no associations were observed with either transforming growth factor (TGF)-alpha or Ki-67 proliferative status. A highly significant relationship was observed between response to endocrine therapy and the presence of bcl-2 protein. Indeed, bcl-2 immunostaining proved to be a more accurate predictor of response than oestrogen receptor status. Patients with elevated bcl-2 immunostaining (particularly those who co-expressed high oestrogen receptor levels) appeared to derive the greatest benefit from endocrine therapy. Our results are paradoxical since it was expected that the bcl-2 protein would counteract the tumour inhibitory effects of endocrine therapies as it is thought to prevent programmed cell death.

In the present study, we have taken the novel approach of using an in vitro model representative of tamoxifen-withdrawal subsequent to clinical relapse to achieve a greater understanding of the mechanisms that serve to maintain the resistant-cell phenotype, independent of any agonistic impact of tamoxifen, to identify potential novel therapeutic approaches for this disease state. Following tamoxifen withdrawal, tamoxifen-resistant MCF-7 cells conserved both drug resistance and an increased basal rate of proliferation in an oestrogen deprived environment, despite reduced epidermal growth-factor receptor expression and reduced sensitivity to gefitinib challenge. Although tamoxifen-withdrawn cells retained ER expression, a sub-set of ER-responsive genes, including pS2 and progesterone receptor (PgR), were down-regulated by promoter DNA methylation, as confirmed by clonal bisulphite sequencing experiments. Following promoter demethylation with 5-Azacytidine (5-Aza), the co-addition of oestradiol (E2) restored gene expression in these cells. In addition, 5-Aza/E2 co-treatment induced a significant anti-proliferative effect in the tamoxifen-withdrawn cells, in-contrast to either agent used alone. Microarray analysis was undertaken to identify genes specifically up regulated by this co-treatment. Several anti-proliferative gene candidates were identified and their promoters were confirmed as more heavily methylated in the tamoxifen resistant vs sensitive cells. One such gene candidate, growth differentiation factor 15 (GDF15), was carried forward for functional analysis. The addition of 5-Aza/E2 was sufficient to de-methylate and activate GDF15 expression in the tamoxifen resistant cell-lines, whilst in parallel, treatment with recombinant GDF15 protein decreased cell survival. These data provide evidence to support a novel concept that long-term tamoxifen exposure induces epigenetic silencing of a cohort of oestrogen-responsive genes whose function is associated with negative proliferation control. Furthermore, reactivation of such genes using epigenetic drugs could provide a potential therapeutic avenue for the management of tamoxifen-resistant breast cancer.

Introduction We have previously reported that induction of epidermal growth factor receptor and ErbB2 in response to antihormonal agents may provide an early mechanism to allow breast cancer cells to evade the growth-inhibitory action of such therapies and ultimately drive resistant cell growth. More recently, the other two members of the ErbB receptor family, ErbB3 and ErbB4, have been implicated in antihormone resistance in breast cancer. In the present study, we have investigated whether induction of ErbB3 and/or ErbB4 may provide an alternative resistance mechanism to antihormonal action in a panel of four oestrogen receptor (ER)-positive breast cancer cell lines. Methods MCF-7, T47D, BT474 and MDAMB361 cell lines were exposed to fulvestrant (100 nM) for seven days, and effects on ErbB3/4 expression and signalling, as well as on cell growth, were assessed. Effects of heregulin β1 (HRGβ1) were also examined in the absence and presence of fulvestrant to determine the impact of ER blockade on the capacity of this ErbB3/4 ligand to promote signalling and cell proliferation. Results Fulvestrant potently reduced ER expression and transcriptional activity and significantly inhibited growth in MCF-7, T47D, BT474 and MDAMB361 cells. However, alongside this inhibitory activity, fulvestrant also consistently induced protein expression and activity of ErbB3 in MCF-7 and T47D cells and ErbB4 in BT474 and MDAMB361 cell lines. Consequently, fulvestrant treatment sensitised all cell lines to the actions of the ErbB3/4 ligand HRGβ1 with enhanced ErbB3/4-driven signalling activity, reexpression of cyclin D1 and significant increases in cell proliferation being observed when compared to untreated cells. Indeed, in T47D and MDAMB361 HRGβ1 was converted from a ligand having negligible or suppressive growth activity into one that potently promoted cell proliferation. Consequently, fulvestrant-mediated growth inhibition was completely overridden by HRGβ1 in all four cell lines. Conclusions These findings suggest that although antihormones such as fulvestrant may have potent acute growth-inhibitory activity in ER-positive breast cancer cells, their ability to induce and sensitise cells to growth factors may serve to reduce and ultimately limit their inhibitory activity.

Using MCF7 breast cancer cells, it has been shown that antihormones promote expression/activity of oestrogen-repressed tyrosine kinases, notably EGFR, HER2 and Src. These inductive events confer responsiveness to targeted inhibitors (e.g., gefitinib, trastuzumab, saracatinib). We observed that these antihormone-induced phenomena are common to ER+HER2– and ER+HER2+ breast cancer models in vitro, where targeting of EGFR, HER2 or Src alongside antihormone improves antitumour response and delays/prevents endocrine resistance. Such targeted inhibitors also subvert acquired endocrine resistant cells which retain increased EGFR, HER2 and Src (e.g., TAMR and FASR models derived after 6–12 months of tamoxifen or Faslodex treatment). Thus, antihormone-induced tyrosine kinases comprise “compensatory signalling” crucial in limiting maximal initial antihormone response and subsequently driving acquired resistance in vitro. However, despite such convincing preclinical findings from our group and others, clinical trials examining equivalent antigrowth factor strategies have proved relatively disappointing. Our new studies deciphering underlying causes reveal that further antihormone-promoted events could be pivotal in vivo. Firstly, Faslodex induces HER3 and HER4 which sensitise ER+ cells to heregulin, a paracrine growth factor that overcomes endocrine response and diminishes antitumour effect of agents targeting EGFR, HER2 or Src alongside antihormone. Secondly, extended antihormone exposure (experienced by ER+ cells prior to adjuvant clinical relapse) can “reprogramme” the compensatory kinase profile in vitro, hindering candidate antigrowth factor targeting of endocrine resistance. Faslodex resistant cells maintained with this antihormone for 3 years in vitro lose EGFR/HER2 dependency, gaining alternative mitogenic/invasion kinases. Deciphering these previously unrecognised antihormone-induced events could provide superior treatments to control endocrine relapse in the clinic.

Splenules are congenital foci of healthy splenic tissue that are separate from the main body but are structurally identical to the spleen, derived from mesenchymal buds on the left side of the mesogastrium and commonly seen in or near the tail of the pancreas. We report a case of a 58-year-old male who was found to have a pancreatic tail mass on contrast-enhanced abdominal CT, which was similarly disguised as a pancreatic tail mass on both magnetic resonance cholangiopancreatography and abdominal MRI. A liver spleen scintigraph with Tc sulfur colloid later proved the mass to be a splenule.

The heterogeneity of oestrogen receptor (ER) expression has been examined in both normal and malignant breast tissue using an immunohistochemical assay. In both instances the ER status and cellular ER negativity were influenced by the patients' menopausal status, with tissues removed from premenopausal women being more often ER-negative, and when ER-positive, containing a high proportion of apparently ER-negative cells. Since the breast is normally regarded as hormone sensitive and since tumour cell ER negativity is apparently under a degree of hormonal regulation, our results suggest that the proportion of breast cancer cells that are ER-negative should be viewed with a degree of caution.

Antihormones are of substantial benefit in treating oestrogen receptor-α positive (ER+) breast cancer. However, their anti-tumour effect is limited by emergence of resistance. Our in vitro studies are highlighting a new underlying concept: that antihormones are not passive bystanders but alongside growth inhibitory effects promote adverse compensatory mechanisms within tumour cells. These mechanisms involve drug-induction of signalling elements normally suppressed by oestrogen (E2)-occupied E R˜ While best exemplified by the tyrosine kinases epidermal growth factor receptor and HER2, microarrays reveal the true diversity of the induced signalling kinases, where their potential to promote resistance is exacerbated under paracrine conditions. Such drug-induced events permit initial ER+ breast cancer cell survival, allow development and maintenance of resistance, and also promote gain of invasiveness under conditions of poor intercellular contact. In addition, prolonged antihormonal exposure is associated with epigenetic silencing of classical E2-induced tumour suppressors, an event which further contributes to resistance. Based on proof of principle experiments targeting induced signalling events alongside antihormones or restoring E2-induced suppressor genes through DNA methylation inhibitor-containing strategies, it is our belief that continued deciphering of these mechanisms will reveal improved treatments for breast cancer.

Qualitative and semiquantitative assessments of oestrogen receptor and progesterone receptor positivity determined on previously immunocytochemically stained slides were performed by eight independent assessors. Concordance beween assessments of steroid receptor status was good ( 24 25 , 96%). Interassessor variations in estimates of positive immunostaining levels were high, varying by between 10 and 75% for individual slides. In 2 cases estimates for the same section ranged between 15% nuclei positive and 90% nuclei positive. Wide variations were also recorded for slides stained for progesterone receptors. Results using an assessment procedure combining staining intensity and percentage positivity estimates were also subject to marked discordance. A computerised image analysis system, also used to assess slides gave results similar to the mean manually determined percentage positivity values. It is suggested that quality control of steroid receptor immunocytochemical quantification be considered and that automated image analysis may represent an accurate and valid means of achieving this.

Aberrant epidermal growth factor receptor (EGFR) signalling, a key feature of a variety of human malignancies, can drive a range of mechanisms underlying tumour growth and progression, including increased cell proliferation, angiogenesis, metastasis and decreased apoptosis. Anti-EGFR therapies, as monotherapies and in combination with chemotherapy, have proved effective in inhibiting these processes both in the clinical and in the preclinical settings. However, only a small cohort of patients have derived significant benefit from this therapy, with both de novo and acquired resistance to these agents evident in a number of recent studies. If we are to improve the effectiveness of such targeted therapies, then there is an urgent need to understand the resistance mechanisms. Here, we describe both non-genomic and genomic mechanisms of resistance to the selective EGFR tyrosine kinase inhibitor gefitinib (IRESSA), which we have identified initially in an EGFR-positive tamoxifen-resistant MCF-7 breast cancer cell line, but more recently in other EGFR-positive cancer types. Importantly, we show that gefitinib, in common with anti-hormonal agents, is not a passive bystander in the cellular response to drug treatment, but plays an active role in promoting signalling pathways that serve to limit its anti-tumour activity and maintain the cellular cohort from which acquired resistance can ultimately evolve. These findings indicate that inductive signalling is an important determinant of response to EGFR-targeted therapies and deciphering such pathways may provide us with the opportunity to design more effective strategies to combat resistance mechanisms and improve response to initial therapy.

Breast cancer inhibition by antihormones is rarely complete, and our studies using responsive models reveal the remarkable flexibility of breast cancer cells in recruiting alternative signalling to limit maximal anti-tumour effects of oestrogen receptor α (ER) blockade. The recruited mechanism involves antihormone-induced expression of oestrogen-repressed signalling genes. For example, epidermal growth factor receptor gene (EGFR) is induced by antioestrogens and maintains residual kinase and ER phosphorylation, cell survival genes, and thereby allows incomplete antihormone response and emergence of resistance. Microarrays are revealing the breadth of antihormone-induced genes that may attenuate growth inhibition, including NFκB, Bag1, 14-3-3ζ and tyrosine kinases, such as HER2 and Lyn. Three concepts are emerging: first, some genes are induced exclusively by antioestrogens, while others extend to oestrogen deprivation; secondly, some are transiently induced, while others persist into resistance; finally, some confer additional adverse features when tumour cells are in an appropriate context. Among the latter is CD59 whose antioestrogen induction may permit evasion of immune surveillance in vivo. Also, induction of pro-invasive genes (including NFκB, RhoE and δ-catenin) may underlie our findings that antioestrogens can markedly stimulate migratory behaviour when tumour intercellular contacts are compromised. Based on our promising studies selectively inhibiting EGFR (gefitinib), NFκB (parthenolide) or CD59 (neutralising antibody) together with antioestrogens, we propose that co-targeting strategies could markedly improve anti-tumour activity (notably enhancing cell kill) during the antihormone-responsive phase. Furthermore, subverting those induced signalling genes that are retained into resistance (e.g. EGFR, NFκB, HER2) may prove valuable in this state. Alongside future deciphering and targeting of genes underlying antioestrogen-promoted invasiveness, embracing of intelligent combination strategies could significantly extend patient survival.

Our previous investigations using cell models of tamoxifen resistance have shown that the acquisition of an endocrine-insensitive state is accompanied by an invasive in vitro phenotype. In this study, we wished to determine whether this was specifically related to partial oestrogen receptor agonists or whether similar phenomena arise with the newer ‘pure’ anti-oestrogens, exemplified by fulvestrant. Our data demonstrate that the development of fulvestrant resistance in two breast cancer cell lines, MCF7 and T47D, is accompanied by an augmented migratory and invasive phenotype in vitro and overexpression of the HGF/SF receptor, c-Met. Importantly, upregulated c-Met expression in these cells facilitates their stimulation by HGF/SF-secreting stromal fibroblasts, leading to the activation of Src, Akt and ERK1/2 and a profound enhancement of their aggressive phenotype in vitro. These effects could be specifically attributable to activation of the c-Met receptor since the inclusion of neutralising antibodies to c-Met, or siRNA-mediated knockdown of c-Met expression, suppressed both invasion and migration stimulated by either exogenous HGF/SF, fibroblast-conditioned medium or following co-culture with fibroblast cells. Together, these in vitro data suggest that the development of fulvestrant resistance in vivo may confer a metastatic advantage to the cells by allowing their migratory and invasive behaviour to be augmented by surrounding stromal cells.

We have previously demonstrated that oestrogen receptor alpha (ERalpha) modulates epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase (MAPK) signalling efficiency in a tamoxifen-resistant MCF-7 breast cancer cell line (Tam-R). In the present study we have investigated whether this cross-talk between EGFR/MAPK and ERalpha signalling pathways is bidirectional by examining the effects of EGFR/MAPK activity on ER functionality in the same cell line. Elevated expression levels of phosphorylated serine 118 (S118) ERalpha were observed in the Tam-R compared to the parental wild type MCF-7 cell line (WT-MCF-7) under basal growth conditions. Phosphorylation of ERalpha at S118 was regulated by the EGFR/MAPK pathway in Tam-R cells being increased in response to amphiregulin (AR) and inhibited by the selective EGFR tyrosine kinase inhibitor, gefitinib and the MEK1/2 inhibitor, PD184352. Recruitment of the co-activators p68 RNA helicase and SRC1 to ERalpha, oestrogen response element (ERE) activity and Tam-R cell growth were similarly EGFR/MAPK-regulated. Chromatin immunoprecipitation (ChIP) studies revealed that in Tam-R cells the ERalpha assembled on the AR gene promoter and this was associated with elevated basal expression of AR mRNA. Furthermore, AR mRNA expression was under the regulation of the EGFR/MAPK and ERalpha signalling pathways. Neutralising antibodies to AR inhibited EGFR/ERK1/2 activity, reduced S118 ERalpha phosphorylation and reduced AR mRNA expression in TAM-R cells. These findings suggest that ERalpha function in Tam-R cells is maintained as a consequence of EGFR/MAPK-mediated phosphorylation at serine residue 118 resulting in the generation of a self-propogating autocrine growth-regulatory loop through the ERalpha-mediated production of AR.