Search

Understanding experiences of and responses to anxiety is foundational to developing robust theories of entrepreneurial behavior. Using open-ended, vignette and graphical elicitation interviews with 77 entrepreneurs, we inductively investigate the experience of and coping responses to anxiety during the entrepreneurship process. We develop a comprehensive and dynamic goal-striving model to explain experiencing and coping with entrepreneurial anxiety by integrating empirical findings with appraisal and control theories. In doing so, we theorize that entrepreneurial anxiety is endogenous to a cyclical conception of goal-striving, such that various sources of anxiety make sense only in consideration of the goals, standards or values to which they pertain. In this regard, entrepreneurs’ coping responses influence four different points of an iterative goal-striving cycle—an insight that moves beyond problematic static and binary coping classifications.

It is well known that bereavement presents major challenges of adjustment to the individuals so affected, but what is much less well recognized is the major challenges bereavement can present to organizations in general and their managers and human resources professionals in particular. This article explores the significance of death for the workplace and argues that organization that fail to give adequate attention to such matters will be poorly placed when it comes to promoting workplace well-being.

Non-small cell lung cancer (NSCLC) molecular profiling is a key factor in treatment selection. Although, patients with NSCLC tumors harboring EGFR or ALK mutations can benefit from personalized therapies, there are currently no approved targeted therapies for KRAS mutant tumors which occur in 25% to 30% of patients with NSCLC. The constitutive activation of the MAPK pathway in these tumors provides a rationale for targeting effectors such as MEK1/2 (MEK) or ERK1/2 (ERK). Inhibitor of MEK kinase have been tested clinically in KRAS-mutant NSCLC but results have been disappointing, possibly because compensatory signaling such as the reactivation of ERK is triggered following the inhibition of MEK, leading to cancer cell survival. Therefore, targeting ERK directly represents an attractive therapeutic approach. As previously described, we have developed a novel, potent and selective ERK inhibitor identified by fragment-based drug discovery which has potent activity in vitro and in vivo. Here, we demonstrate the activity of this lead compound in KRAS-mutant NSCLC models. Our novel ERK inhibitor was tested in a panel of 440 human cancer cell lines of which the KRAS NSCLC population was identified as particularly sensitive. 62% of the KRAS-mutant NSCLC cell lines tested, exhibited antiproliferative IC50s ranging from 1 nM to 500 nM. This lead compound also inhibited ERK downstream signaling in KRAS NSCLC models both in vitro and in vivo. Indeed, the phosphorylation level of the ERK substrate, RSK, was strongly decreased in HCC-44 and Calu-6 xenograft tumors 2h after oral administration of the lead compound at 50 mg/kg. Levels of pRSK remained below those of untreated tumors for up to 16h in HCC-44 tumors and 24h in Calu-6 tumors. We also confirmed that, the ERK inhibitor conferred a decrease in phosphorylation of ERK itself in both models. The inhibition of ERK signaling corresponded to significant anti-tumor activity in these models with a daily oral administration of 50 mg/kg compound leading to significant tumor regression in subcutaneous models of HCC-44 (18.3% T/C) and Calu-6 (8.9% T/C) xenograft tumors. This work demonstrates the in vitro and in vivo activity of a novel, highly potent, selective ERK inhibitor in models of KRAS-mutant NSCLC. These data support the further optimisation of this series of compounds for clinical development. Citation Format: Aurelie Courtin, Luke Bevan, Tom Heightman, Birikiti Kidane, Justyna Kucia-Tran, John Lyons, Sandra Muench, Alpesh Shah, Lukas Stanczuk, Neil Thompson, Nicola Wallis, Nicola Wilsher, Joanne Munck. A novel ERK1/2 inhibitor has potent activity in KRAS-mutant non-small cell lung cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5781.

Undergoing a traumatic experience can be a life-changing event, having a significant impact on individuals, families, communities, workplaces and societies. Traumatology is therefore a complex field of study demanding a sophisticated level of understanding to serve as a theory base. This article explores the potential for existentialist philosophy to make an important contribution to our understanding of trauma and its effects. It presents trauma as an existential injury and explores the psychosocial basis of traumatic experience — that is, conceptualising trauma as having both psychological and sociological dimensions, the combination of which has profound existential resonances. While the theoretical ideas discussed can be applied to trauma at any stage in the life course, this paper focuses in particular on childhood trauma. Consequently, child abuse is used as an example of how trauma can have a significant (and detrimental) effect on identity development, invoking a need for a commitment to trauma re...

Objective: To pilot a brief cognitive behavioral therapy-based intervention designed to enhance client empowerment and the therapeutic alliance with the aim of reducing clozapine discontinuation. Design: Randomized controlled trial with two conditions: therapy (Alliance Enhancement Therapy [AET]) and control (psychoeducation alone). Assess ments took place at: baseline, twelve weeks and twenty-four weeks (follow-up). The primary outcomes were levels of empowerment, alliance with the clinical team and clozapine discontinuation. Secondary outcomes included insight and other clinical measures. Methods: Treatment-resistant patients who had a diagnosis of schizophrenia, had been registered for clozapine in the previous month and who consented, were independently randomized to active versus control therapy. Results: Thirty-nine patients entered the study. Both groups improved on the main measures with no differential effects of AET intervention. However, patients who attended for more than five sessions showed a differen tial enhancement of working alliance. Conclusions: Although the active therapy showed no general improvement, it did provide some added value over psychoeducation alone when patients attended several sessions. Effective methods of reducing clozapine discontinuation and engaging patients in psychosocial interventions are needed.

We have witnessed in recent times an increasing emphasis on the need to identify outcomes. This paper explores the significance of this development and relates it to previous work on the subject, notably the long-standing concept of systematic practice. Possible objections to the use of systematic practice (and therefore, by extension, outcome-focused practice) are identified and addressed. Some key implications for practice are identified. The paper seeks to distance outcome-focused practice from the problems associated with managerialism.

Since the discovery that activating mutations of the Ras GTPase were associated with 30% or more of human cancers, the RAF/MEK/ERK pathway has been the focus of intense drug discovery effort. Within the new class of molecularly targeted anti-cancer agents progressing through the late stages of clinical development, BAY 43-9006 and PD0325901 have shown considerable promise.

Objectives. The authors investigated the effects of cigarette smoking on midlife cognitive performance. Methods. Multiple regression was used to test the association between cigarette smoking and changes in cognitive test scores among male and female members of the British 1946 birth cohort aged between 43 and 53 years. Results. Smoking was associated with faster declines in verbal memory and with slower visual search speeds. These effects were largely accounted for by individuals who smoked more than 20 cigarettes per day and were independent of sex, socioeconomic status, previous (adolescent) cognitive ability, and a range of health indicators. Conclusions. The present results show that heavy smoking is associated with cognitive impairment and decline in midlife. Smokers who survive into later life may be at risk of clinically significant cognitive declines.

Antagonists of cellular inhibitor of apoptosis proteins (cIAPs) have been shown to activate the alternative NF-κB pathway and to cause release of pro-inflammatory cytokines, including TNFα. In addition to a direct effect on tumor cell apoptosis, this cytokine generation may be detected by the immune system and result in priming of tumor killing by cytotoxic T cells. The release of pro-inflammatory cytokines following treatment with a cIAP antagonist could have several different effects on the innate and adaptive immune system dependent, in part, on where precisely the cytokines are generated or sensed by the immune cells. For example, this pro-inflammatory effect may co-stimulate the maturation of dendritic cells and enhance antigen presentation to naïve T cells. Alternatively, it may boost the effector phase of the adaptive response by enhancing CD8 differentiation or cytotoxic T cell killing of tumor cells. Here we report that ASTX660, an oral IAP antagonist, can potentiate the anti-tumor effect of anti-PD-L1 treatment in a range of syngeneic mouse tumor models. Subcutaneous CT26 and H22 tumors in BALB/c wild type mice were insensitive to intermittent parenteral anti-PD-L1 antibody therapy (250 µg per animal). Daily oral ASTX660 treatment (16 – 25 mg/kg Days 1-7) caused stasis of H22 tumor growth and modest but significant CT26 tumor growth inhibition. The combination of both anti-PD-L1 antibody and ASTX660 resulted in enhanced tumor growth inhibition over ASTX660 alone in both models. Survival of mice bearing CT26 tumors was significantly prolonged by the combination therapy. While other models were sensitive to both agents as single-agents (e.g. EMT6), some were insensitive to single-agents and combination (e.g. 4T1, B6F10). Previously, we have reported ASTX660 elevates plasma inflammatory signals, such as serum amyloid P (analogous to human C-reactive protein), in mice. We have also found it increases TNFα expression in cells in vitro. To understand whether these effects mediate the potentiation of the anti-PD-L1 antibody, we are investigating the consequences of the combination on the immune phenotype within these tumor models, including characterization of the tumor-infiltrating leukocytes and cytokine release. ASTX660 is currently being evaluated in a Phase I clinical trial (NCT02503423). Our investigation into the effects of combining ASTX660 with immune checkpoint inhibitors will not only evaluate the potential of such combination therapies in the clinic but also contribute towards understanding of the mechanism of immune-mediated tumor cell killing in vivo. Citation Format: Tomoko Smyth, Shingo Tsuji, Gotaro Tanaka, Yoko Nakatsuru, John Lyons, Neil Thompson. ASTX660, a dual XIAP and cIAP antagonist, potentiates the anti-PD-L1 antibody therapy in mouse tumor models. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2016 Oct 20-23; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2017;5(3 Suppl):Abstract nr A33.

• Summary: This article explores models and strategies for developing empowering forms of social work practice with older people. • Findings: Social work with older people has strong roots in a predominantly medical model in which the primary objective is to ensure that care is provided. While social work with other client groups has made major steps forward in developing less medicalized approaches, the work undertaken with older people has seen far less progress. This article examines the differences between a care model and an empowerment model, identifies some of the barriers standing in the way of movement from one to the other and considers ways of responding to such barriers. • Applications: The authors identify strategies for developing empowering forms of practice.

We have previously described the development and initial validation of a telephone administered cognitive test battery (TACT). This report investigates the retest reliability of the TACT battery between telephone administration and face-to-face administration and measures the concurrent validity of the test components against a standard test of cognitive ability, the WAIS-RUK. Data were collected on 27 participants aged 62–63 years. There was a two- to 10-month interval between time 1 (telephone) and time 2 (face-to-face) administration. Intra-class correlation coefficients for telephone versus face-to-face administration of the TACT were satisfactory for all component measures except for ‘object rotation’ and WAIS similarities. There was no evidence of systematic cheating on the telephone-administered test. Tests of concurrent validity showed stronger correlations for the TACT battery components with verbal tests rather than performance tests, as measured by the WAIS-RUK. A few administration difficulties are noted and recommendations for change are outlined. The TACT is a convenient assessment tool with potential for measuring cognitive change in epidemiological studies. Copyright © 2001 Whurr Publishers Ltd.

Background Persistent auditory hallucinations are common, disabling and difficult to treat. Cognitive behavioural therapy is recommended in their treatment though there is limited empirical evidence of the role of cognitive factors in the formation and persistence of voices. Low self-esteem is thought to play a causal and maintaining role in a range of clinical disorders, particularly depression, which is prevalent and disabling in schizophrenia. It was hypothesized that low self-esteem is prominent in, and contributes to, depression in voice hearers. Methods Beliefs about persistent auditory hallucinations were investigated in 82 patients using the Beliefs About Voices Questionnaire — revised in a cross-sectional design. Self-esteem and depression were assessed using standardized measures. Results Depression and low self-esteem were prominent as were beliefs about the omnipotence and malevolence of auditory hallucinations. Beliefs about the uncontrollability and dominance of auditory hallucinations and low self-esteem were significantly correlated with depression. Low self-esteem did not mediate the effect of beliefs about auditory hallucinations- both acted independently to contribute to depression in this sample of patients with schizophrenia and persistent auditory hallucinations. Conclusions Low self-esteem is of fundamental importance to the understanding of affective disturbance in voice hearers. Therapeutic interventions need to address both the appraisal of self and hallucinations in schizophrenia. Measures which ameliorate low self-esteem can be expected to improve depressed mood in this patient group. Further elucidation of the mechanisms involved can strengthen existing models of positive psychotic symptoms and provide targets for more effective treatments.

Preface Acknowledgements Introduction PART I: WORKPLACE PROBLEMS Stress N.Thompson Conflict, Aggression and Bullying N.Thompson & L.Brooksbank Drug and Alcohol Problems I.Madoc Jones Mental Health Problems S.Desai Racism G.Singh Loss, Grief and Trauma N.Thompson & S.Thompson PART II: PROMOTING WELL-BEING Learning and Development J.Bates Leadership P.Gilbert Managing Sickness Absence M.Tehan Women-friendly Workplaces B.Metcalf Spirituality in the Workplace B.Moss PART III: INTERNATIONAL PERSPECTIVES A United States Perspective S.de Mello A Hong Kong Perspective S.Ng An Australian Perspective J.Bottomley A Greek Perspective V.Ioakimidis An Indian Perspective G.Prem Singh Conclusion References Index

For many people the topic of sickness absence is quite straightforward: people on sick leave fall into one of two categories, those who are ‘genuinely’ ill and who deserve support and those who are ‘malingering’ who deserve contempt, if not actual punishment. The reality of the situation is far more complex than this. In this chapter, we shall see that what constitutes ‘sickness’ or ‘illness’ is subject to debate and competing theoretical understandings, especially when mental illness is the topic under consideration. We shall also see that the reasons for sickness absence are many and varied, and that there are various factors involved at various levels. I shall therefore be arguing that simple solutions are unlikely to work and may actually prove counterproductive. A much more sophisticated understanding is called for, one that connects with the wider field of workplace well-being and the emerging knowledge base about such matters.

Background Schizophrenia with an onset in adolescence is known to be associated with a poorer outcome and cognitive difficulties. These impairments have an impact on quality of life and represent treatment targets. Cognitive remediation therapy (CRT) attempts to improve cognitive deficits by teaching information processing strategies through guided mental exercises. The objective of this study is to evaluate the efficacy of CRT in alleviating cognitive deficits compared to treatment as usual and explore the mediating and moderating effects of cognitive improvement. Method Single-blind randomized controlled trial with two groups, one receiving CRT (N21) and the other standard care (N19) assessed at baseline, 3 months (post therapy) and follow-up (3 months post therapy). Participants were recruited from specialist inpatient and community mental health services and were young patients with recent onset schizophrenia (average age of 18) and evidence of cognitive and social behavioural difficulties. The intervention was individual cognitive remediation therapy delivered over a period of 3 months with at least three sessions per week. The main outcome measures were cognition (memory, cognitive flexibility and planning) and secondary outcomes (symptoms, social contacts and self-esteem). Results Compared to standard care, CRT produced significant additional improvements in cognitive flexibility as measured by the Wisconsin Card Sort Test (WCST). Therapy moderated the effects of improved planning ability on symptoms such that improvements only had a beneficial effect when they were achieved in the context of CRT. Improvements in cognition in all domains had a direct effect on social functioning and improvements in WCST had a direct effect on overall symptom improvement. Conclusions Cognitive remediation therapy can contribute to the improvement in WCST even in adolescents. The changes in cognitive outcomes also contributed to improvements in functioning either directly or solely in the context of CRT. Evidence of the mediator and moderator effects of cognitive changes should lead to more effective therapy development.

Background: Kinase inhibitors have been used successfully in the clinic, but relapse is common due to the emergence of resistance. Inhibition of HSP90 leads to the depletion of oncogenic ‘client’ proteins and the simultaneous inhibition of many signalling pathways. As such, the use of HSP90 inhibitors to overcome resistance has been widely investigated. Onalespib (AT13387) is a potent, second generation HSP90 inhibitor, which has been studied in many preclinical models of kinase inhibitor resistance. Recent findings indicate that an upfront combination of onalespib and either vemurafenib or crizotinib, in models of mutant BRAF melanoma or ALK-translocated non-small cell lung cancer (NSCLC), can delay the emergence of resistance to these therapies. Here we have extended this work to a combination of onalespib and erlotinib in an EGFR-driven NSCLC model. Methods: Mice bearing HCC827 tumor xenografts were dosed with either 12.5 mg/kg erlotinib po qd, or a combination of 12.5 mg/kg erlotinib and 55 mg/kg onalespib ip qw for 52 weeks. Results: Initially both the erlotinib single-agent and onalespib/erlotinib combination treatments significantly inhibited tumor growth of the EGFR-driven NSCLC HCC827 xenograft model; all tumors in the monotherapy and combination groups regressed rapidly and achieved complete response (CR) (median times to CR were 79 and 56 days for monotherapy and combination treatments respectively). However, after 20 weeks of continuous treatment, tumor relapse was observed in one of the xenografts dosed with erlotinib only and this was followed by regrowth of a further 2 tumors in this group over the 52-week study period, with these tumors reaching 50% of the original tumor volumes by 26 and 46 weeks. Of the remaining tumors, 5 out of 6 were detectable at the end of the study. In comparison, tumor growth remained inhibited in the group treated with the erlotinib/onalespib combination; no tumors were observed to regrow over the course of the study and none (of 9) were palpable when treatments were terminated. This suggests that while treatment with monotherapy erlotinib in this model leads to relapse, as seen in the clinic, combination treatment with onalespib can delay the emergence of resistance. Conclusions: These data demonstrate that an upfront combination of onalespib and erlotinib can delay the emergence of resistance in an EGFR-driven xenograft model, suggesting there is therapeutic potential for an upfront erlotinib/onalespib combination in the clinic. Onalespib is currently being tested in a Phase 2 clinical trial in combination with crizotinib in ALK-positive NSCLC. The preclinical data presented here, alongside our previous data on combinations of onalespib with vemurafenib or crizotinib, suggest that the concept of using an HSP90 inhibitor combination upfront in the clinic to delay resistance could be extended to further targeted therapies. Citation Format: Aurélie Courtin, Tomoko Smyth, Keisha Hearn, John Lyons, Neil Thompson, Nicola G. Wallis. The HSP90 inhibitor, onalespib (AT13387), delays the emergence of resistance to erlotinib in an EGFR-driven xenograft model. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2688. doi:10.1158/1538-7445.AM2015-2688

The fibroblast growth factor (FGF) signaling axis is increasingly implicated in tumorigenesis and chemoresistance. Alterations in FGFR family members including focal amplification of FGF receptor 1 (FGFR1), mutations in FGFR 2, 3 and 4, translocations involving FGFR 2 and FGFR3, as well as amplification or transcriptional upregulation of various ligand family members have been associated with tumor growth and survival, suggesting that FGFR inhibitors may be a viable therapeutic option in subsets of various disease settings. A number of agents targeting the FGF signaling axis including small-molecule FGFR targeted agents, with diverse kinase inhibitory and pharmacological profiles, are currently in clinical development. JNJ-42756493 (first disclosure of the structure) has a pharmacological profile that is differentiated from other agents in this class currently under investigation. JNJ-42756493 displays single digit nanomolar FGFR (1, 2, 3 4) tyrosine kinase inhibitory activity. JNJ-42756493 inhibited recombinant FGFR kinase activity in vitro and suppressed FGFR signaling and growth in engineered cell lines and tumor cell lines dependent upon deregulated FGFR expression. JNJ-42756493 demonstrated highly specific tumor inhibitory effects in FGFR1-4 dependent cell lines, in vitro cell lines based xenografts and direct patient derived xenografts, with no discernible activity in models that were not dependent on FGFR signaling. JNJ-42756493 showed favorable drug like properties and displayed a high distribution to lung, liver and kidney tissue. JNJ-42756493 was well tolerated at efficacious doses and resulted in potent dose-dependent antitumor activity accompanied by pharmacodynamic modulation of tumor FGFR and downstream pathway components. Data presented here highlights JNJ-42756493 as a novel, highly potent and selective small-molecule inhibitor of all four known active FGFR kinase family members with potent antitumor activity against FGFR-dependent tumor models. These data, together with emerging observations from our ongoing Phase 1 clinical trial, position JNJ-42756493 as a differentiated FGFR 1, 2, 3 and 4 kinase inhibitor and support its continued clinical development in lung cancer and other malignancies associated with aberrant FGFR signaling. Citation Format: Timothy Perera, Eleanora Jovcheva, Jorge Vialard, Tinne Verhulst, Norbert Esser, Berthold Wroblowski, Ron Gilissen, Eddy Freyne, Peter King, Suso Platero, Olivier Querolle, Laurence Mevellec, Christopher Murray, Lynsey Fazal, Gordon Saxty, George Ward, Matthew Squires, Neil Thompson, David Newell, Patrick Angibaud. JNJ-42756493 is an inhibitor of FGFR-1, 2, 3 and 4 with nanomolar affinity for targeted therapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1738. doi:10.1158/1538-7445.AM2014-1738

Background: Although Epidermal Growth Factor Receptor (EGFR)-driven non-small cell lung cancer (NSCLC) can be successfully treated with EGFR inhibitors such as erlotinib, relapse is common due to the development of resistance. Methods to improve response and delay resistance are therefore of value. Inhibition of the chaperone, HSP90, leads to the depletion of many client proteins, including EGFR, and has the capacity to simultaneously affect many signalling pathways, offering an alternative strategy for targeting EGFR-driven disease. AT13387 is a potent, second generation HSP90 inhibitor currently being tested in Phase II clinical trials. Here we investigated the effects of combining AT13387 and erlotinib in models of EGFR-driven NSCLC. Results: AT13387 single-agent treatment was effective in EGFR-driven NSCLC xenograft models, significantly inhibiting tumor growth of both HCC827 and NCI-H1650 xenograft tumors when dosed once weekly (see table). As expected, treatment with erlotinib caused significant tumor regression in all HCC827 tumors, but was less effective in the NCI-H1650 model; its PTEN status conferring a reduction in sensitivity. However, combination of AT13387 with erlotinib led to a further enhancement of tumor growth inhibition over either of the monotherapies in both of these models. All HCC827 tumors treated with the combination regressed further (by at least 80%), and regression was also now observed in all NCI-H1650 tumors. These data demonstrate that combination with AT13387 has the potential to increase response, despite the differing initial sensitivities to erlotinib of these models. The combination was well tolerated. Effects of AT13387 and erlotinib on EGFR-driven xenograftsCell lineGenetic BackgroundT/C(Median RTV, treated / control)AT1338755 mg/kg ip 1qwErlotinib12.5 mg/kg po qdCombinationHCC827(Day 32)EGFR Del E746_A75026%17%(47% regression)6%(84% regression)NCI-H1650(Day 31)EGFR Del E746_A750/PTEN del35%36%6%(50% regression) Conclusions: AT13387 was shown to improve response when combined with erlotinib in EGFR-driven xenograft models. These data suggest that there is therapeutic potential in an upfront combination of an HSP90 inhibitor, such as AT13387, with erlotinib and support clinical investigation of such a combination. Citation Format: Tomoko Smyth, Jon Lewis, Keisha Hearn, Neil Thompson, John Lyons, Nicola G. Wallis. The HSP90 inhibitor, AT13387, combined with erlotinib improves response in EGFR-driven xenograft models of NSCLC. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1794. doi:10.1158/1538-7445.AM2014-1794

The inhibitor of apoptosis proteins (IAP) are key regulators of anti-apoptotic and pro-survival signaling pathways. Overexpression of IAPs occurs in various cancers and has been associated with tumor progression and resistance to treatment. IAP antagonists activate the E3 ligase function of cIAP1 and stimulate rapid autoubiquitylation and proteosomal degradation of both cIAP1 and cIAP2. Elimination of these proteins leads to a switch in TNFα signalling from being pro-survival to being pro-apoptotic. However, a strong pro-apoptotic effect from cIAP loss cannot be achieved without sustained antagonism of XIAP-mediated caspase inhibition. Therefore, a best in class profile for IAP antagonists requires potent dual antagonism of cIAP1 and XIAP. Astex has used fragment based-drug discovery to develop a second generation of IAP antagonists, which are non-peptidomimetic and do not contain an alanine as a warhead. This series has the ability not only to efficiently degrade cIAP1 but also to potently antagonize XIAP, delivering a dual cIAP1/XIAP inhibitory profile which is not apparent in the first generation of IAP antagonists based on an alanine warhead. Here, we report the structural understanding of the unique molecular profile of the series together with the enhanced activity of these compounds in melanoma cancer stem cells (CSC). CSC populations are more resistant to apoptosis than the bulk cell population and they have been associated with resistance to cancer therapy, relapse and cancer progressions. Blockade of the apoptotic pathway by up-regulation of anti-apoptotic factors has been implicated in conferring resistance in CSC fractions and increased XIAP expression has also been reported in these cells. We have analysed the CD133+ population of three melanoma cell lines (SK-MEL-2, SK-MEL-5 and SK-MEL-28) and measured activation of caspase-3 (NucView™ cell staining) after treatment with IAP antagonists in presence of TNFα. Our potent dual cIAP1/XIAP antagonists (XIAP EC50 35 nM in cells). The enhanced XIAP potency of our compounds is overriding the resistance in CSC subpopulations, highlighting the importance of dual antagonism in promoting efficient induction of apoptosis. Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A55. Citation Format: Gianni Chessari, Maria Ahn, Keisha Hearn, Christopher N. Johnson, Jon Lewis, Neil Thompson, George Ward, Pamela Williams. Potent, dual cIAP1/XIAP antagonists induce apoptosis in a melanoma stem cell population. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A55.

Melanoma is a highly aggressive malignancy with an exceptional ability to develop resistance and no curative therapy is available for patients with metastatic disease. Inhibitor of apoptosis proteins (IAP) play a key role in preventing cell death by apoptosis. In normal cell, IAPs are highly regulated by endogenous antagonists (e.g. SMAC) but in melanoma cell lines and in patient samples expression levels of IAPs are generally high and depleting IAPs by siRNA tended to reduce cell viability, with XIAP reduction being the most efficient [1]. Small molecule IAP antagonists have the ability to switch IAP-controlled pro-survival pathways towards apoptosis and cell death. Recent evidence suggests that a true dual antagonist of both cIAP1 and XIAP will promote an effective apoptotic response through generation of death-inducing ripoptosome complexes, with resultant caspase activation [2, 3]. We have used our fragment-based drug discovery technology PyramidTM to derive a non-peptidomimetic IAP antagonist, AT-IAP, which does not have an alanine warhead and has nanomolar cellular potency for both XIAP and cIAP1. Initial pharmacokinetic and pharmacodynamic modeling of AT-IAP in mice bearing the MDA-MB-231 cell line indicated that daily oral dosing of AT-IAP at 30 mg/kg ensures high concentrations of compound in tumor and plasma over a 24 h period with resultant inhibition of both XIAP and cIAP1 and induction of apoptosis markers (cleaved PARP and cleaved caspase-3). In this paper, we describe the characterization of AT-IAP in melanoma models. An in vitro cell line proliferation screen demonstrated that 36% of melanoma cell lines exhibited enhanced sensitivity to AT-IAP, which was improved on addition of exogenous 1 ng/ml TNF-α (92% of cell lines were sensitive to AT-IAP + TNF-α). Sensitivity of melanoma cells to AT-IAP has also been confirmed in a panel of 20 primary melanoma tumors in colony formation assays set up in the presence and absence of added TNF-α. Finally, a set of biomarkers has been identified and used to predict single agent activity of AT-IAP in a range of melanoma cell line and patient derived xenograft models. [1] Engesaeter et al., Cancer Biology & Therapy, 2011, 12 (1), 47 [2] Ndubaku et al., ACS Chem Biol., 2009, 4 (7), 557 [3] Meier, P., Nat Rev. Cancer, 2010, 10 (8), 561 Citation Format: Gianni Chessari, Ahn Maria, Ildiko Buck, Elisabetta Chiarparin, Joe Coyle, James Day, Martyn Frederickson, Charlotte Griffiths-Jones, Keisha Hearn, Steven Howard, Tom Heightman, Petra Hillmann, Aman Iqbal, Christopher N. Johnson, Jon Lewis, Vanessa Martins, Joanne Munck, Mike Reader, Lee Page, Anna Hopkins, Alessia Millemaggi, Caroline Richardson, Gordon Saxty, Tomoko Smyth, Emiliano Tamanini, Neil Thompson, George Ward, Glyn Williams, Pamela Williams, Nicola Wilsher, Alison Woolford. AT-IAP, a dual cIAP1 and XIAP antagonist with oral antitumor activity in melanoma models. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2944. doi:10.1158/1538-7445.AM2013-2944

Background: Treatment with kinase inhibitors, although initially effective in the clinic, frequently leads to resistance and relapse. Multiple mechanisms of resistance have been identified including mutation of the original targeted kinase or upregulation of downstream or parallel signaling pathways. Many oncogenic kinases are clients of HSP90, including KIT, B-RAFV600E and EML4/ALK and remain dependent on HSP90 even when secondary mutations arise. In addition, proteins in many signaling pathways also rely on HSP90 activity and are depleted when HSP90 is inhibited. Treatment with an HSP90 inhibitor is therefore a promising approach for addressing multiple mechanisms of kinase inhibitor resistance. AT13387, a potent, fragment-derived HSP90 inhibitor, is currently under evaluation in a Phase II gastrointestinal stromal tumor (GIST) trial in combination with imatinib. AT13387 is effective in both imatinib-sensitive and imatinib-resistant GIST models, demonstrating HSP90 inhibition can overcome kinase inhibitor-resistance caused by secondary mutations in the drug target client, in this case KIT. Here we describe the activity of AT13387 in vemurafenib-resistant melanoma models. Multiple mechanisms of vemurafenib resistance have been identified. These frequently involve upregulation of the AKT (e.g. PTEN loss) or MEK/ERK (e.g. Ras mutation, BRAF splice variants) signaling pathways, rather than mutation at the vemurafenib-binding site in BRAFV600E. Results: The effect of HSP90 inhibition on acquired vemurafenib resistance was investigated by generating resistant clones from the A375, vemurafenib-sensitive, cell line by continuous exposure to 2 μM vemurafenib. Proliferation and signalling in the vemurafenib-resistant pool of cells were insensitive to vemurafenib but potently inhibited by AT13387, indicating that HSP90 inhibition can overcome an acquired mechanism of vemurafenib resistance. In established cell lines, two different mechanisms of vemurafenib resistance were investigated. The A2058 cell line is PTEN-null and overcomes BRAFV600E inhibition through upregulation of the AKT pathway, whilst RPMI7951 overexpresses COT, upregulating the MEK/ERK pathway and bypassing inhibition of BRAFV600E. The proliferation of both these cell lines was inhibited by AT13387 with GI50s of 31 and 37 nM respectively. AT13387 treatment depleted the levels of the client proteins, BRAF and CRAF, and in the RPMI7951 cell line, levels of COT were also seen to decrease. Signaling through both the AKT and MEK/ERK pathways was inhibited as indicated by a decrease in the levels of phosphoAKT, phosphoS6 and phosphoERK. This suggests that HSP90 inhibition can overcome upregulation of either the AKT or MEK/ERK pathways and so counteract multiple mechanisms of vemurafenib resistance. AT13387 and vemurafenib could be combined in both the A2058 and RPMI7951 cell lines without any antagonistic effects, whilst culturing A375 cells in the presence of both AT13387 and vemurafenib prevented the development of vemurafenib-resistant clones. These data suggest that not only can AT13387 treatment overcome established resistance but that in combination it may also be a means of delaying the emergence of this resistance. Conclusions: We have demonstrated that AT13387 can overcome kinase inhibitor resistance in both imatinib-resistant GIST and vemurafenib-resistant melanoma models. This suggests HSP90 inhibition may be a promising approach for combating multiple mechanisms of resistance to kinase inhibitors in the clinic and that AT13387 combinations may have the potential to delay the emergence of resistance.

XIAP and cIAP1 are members of the inhibitor of apoptosis (IAP) protein family. Both proteins have the ability to attenuate apoptosis induced through intrinsic and extrinsic stimuli via inhibition of caspase-3, -7, -8 and -9. The defining feature of both XIAP and cIAP1 is the presence in their protein sequence of 3 Baculoviral IAP Repeat (BIR) domains, which are necessary for their antiapoptotic activity. The mitochondrial protein SMAC uses its N-terminal region (AVPI) to interact with BIR domains and deactivate the antiapoptotic function of IAPs. Several companies and academic groups have active programs developing SMAC peptidomimetic compounds based on the AVPI motif. In general, those compounds have the tendency to be cIAP1 selective like their tetrapeptide progenitor (AVPI IC50 values for XIAP-BIR3 and cIAP1-BIR3 are 0.3 uM and 0.016 uM respectively). Using our fragment-based screening approach, PyramidTM, we identified a non-peptidomimetic chemotype which binds with similar potency to the BIR3 domain of both XIAP and cIAP1. Hit optimisation using a structure based approach led to the discovery of potent true dual XIAP and cIAP1 antagonists with good in vivo physico-chemical profile and no P450 or hERG liabilities. Dual XIAP/cIAP1 inhibitors have potential for more effective apoptosis and less toxicity associated with cytokine production. Compounds were initially characterised in fluorescence polarisation binding assays using XIAP-BIR3 or cIAP1-BIR3 domains. Robust induction of apoptosis was observed in two sensitive breast cancer cell lines (EC50s well below 0.1 uM in EVSA-T and MDA-MB-231); whilst HCT116 cells (colon cancer) were insensitive (unless exogenous TNF-α was added). This in vitro cell line killing was demonstrated to correlate closely with cIAP1 antagonism and hence a parallel cell assay was established to measure XIAP antagonism. An engineered HEK293 cell line was stably co-transfected with full length FLAG-tagged human XIAP cDNA and full length (untagged) human caspase-9 cDNA. Inhibition of caspase-9 binding to XIAP was measured in immunoprecipitation assays. This gave us a sensitive read-out for XIAP antagonism in cells which could be plotted against the most sensitive cell killing read-out (from the EVSA-T cell line) to establish relative XIAP vs cIAP1 selectivities and to select dual antagonists of both IAPs. Potent compounds (HEK293-EC50 Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2018. doi:1538-7445.AM2012-2018

Background: Methionine aminopeptidase (MetAP) 2 is one of the two eukaryotic enzymes responsible for cleaving the N-terminal methionine from newly synthesized polypeptides to allow further post-translational modifications such as myristoylation to take place. The enzyme is the target of the anti-angiogenic natural product, fumagillin and so is believed to play a role in angiogenesis. Fumagillin analogues have shown activity in several disease models including oncology, inflammation and obesity indicating MetAP2 is a promising target in a number of indications. The semi-synthetic fumagillin analogue, TNP470, has shown activity in a Phase I/II cancer trial, suggesting that MetAP2 is a good oncology target. Here we describe the discovery, optimization and anti-tumor activity of fragment-derived MetAP2 inhibitors. Results: We identified fragment hits to MetAP2 using our fragment-based screening approach, Pyramid™. These were optimized by structure-based drug design to novel, potent lead compounds with sub-100 nM potency against the isolated MetAP2 enzyme. The two most advanced compounds inhibited proliferation of HUVECs with potencies of 130 nM and 300 nM. Levels of the MetAP2 substrate, Met-14-3-3, were shown to increase on treatment of HUVECs with these compounds indicating that Met-14-3-3 was not being processed and hence MetAP2 was being inhibited. The compounds also inhibited HUVEC tubule formation demonstrating their anti-angiogenic properties. The two lead compounds were further tested in vivo. Both compounds were well tolerated at doses up to 200 mg/kg bid. Levels of Met-14-3-3 were seen to increase in the thymus and spleen (where high expression of MetAP2 has been reported) of mice treated with the compounds, indicating again that MetAP2 was being inhibited in these tissues. Compound 1 was tested in a mouse HCT116 xenograft model. Mice were subcutaneously inoculated with HCT116 cells and oral dosing at 200 mg/kg bid started one day later. Tumor growth was inhibited in treated mice compared with control and growth inhibition was greater in Compound 1 treated mice (T/C 46%) compared with mice treated with 30 mg/kg TNP470 subcutaneously q2d (T/C 61%). Conclusions: The compounds described here are novel small-molecule inhibitors of MetAP2. Their promising tumor growth inhibitory properties merit their testing in further tumor models and potentially other indications. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2315. doi:1538-7445.AM2012-2315

Background: Mutations in BRAF are found in approximately 50% of melanomas. Vemurafenib, the selective mutant BRAF inhibitor, is an effective treatment in this disease but is limited by the onset of resistance. A number of mechanisms of resistance to RAF inhibitors have been described, including alternative mechanisms for activating the MEK-ERK and AKT pathways. HSP90 inhibitors affect clients in both these pathways and so it has been suggested that HSP90 inhibition is a potential mechanism for overcoming resistance to RAF inhibitors in melanoma. Results: AT13387 is a fragment-derived, potent HSP90 inhibitor, which is currently being evaluated in clinical trials. AT13387 inhibited cell proliferation in a range of melanoma cell lines, including cell lines with different mechanisms of resistance to vemurafenib (See Table). AT13387 treatment of melanoma cell lines resulted in the induction of HSP70, a marker of HSP90 inhibition, and depletion of HSP90 client proteins including BRAF and AKT. The levels of phospho-ERK, phospho-AKT and phospho-S6 were also depleted in both vemurafenib-sensitive (A375) and vemurafenib-resistant (A2058) lines indicating that the MEK-ERK and AKT signaling pathways were both inhibited. This demonstrates that vemurafenib resistance mediated by upregulation of the AKT pathway can be overcome by HSP90 inhibition. In vivo, AT13387 significantly inhibited growth of an A375 melanoma xenograft. Client proteins, including BRAF, CRAF and AKT were depleted in xenograft tissue and the MEK-ERK and AKT signaling pathways were again inhibited. Conclusions: These results demonstrate the activity of AT13387 in both vemurafenib-sensitive and -resistant models and show that HSP90 inhibition results in downregulation of signaling pathways that may be activated as a result of resistance to RAF inhibitors. These data support further clinical evaluation of AT13387 in melanoma. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2772. doi:1538-7445.AM2012-2772

Background: Activating mutations in the receptor tyrosine kinase, KIT, are found in the majority of gastrointestinal stromal tumors (GIST) and further secondary resistance mutations in KIT frequently arise upon treatment with tyrosine kinase inhibitors such as imatinib. KIT and its mutant forms are sensitive clients of HSP90 and it has been suggested that HSP90 inhibition could be an effective treatment for both imatinib-sensitive and imatinib-resistant GIST, which can occur simultaneously in different clones within the same patient. Methods: AT13387 is a fragment-derived, potent HSP90 inhibitor, which is currently being evaluated in clinical trials. To evaluate its anti-tumor activity against GIST, AT13387 was tested in both imatinib-sensitive (GIST882, GIST-PSW) and imatinib-resistant (GIST430, GIST48) in vitro and in vivo GIST models. Results: AT13387 inhibited the proliferation of GIST cell lines at sub-100 nM potencies, irrespective of their sensitivity to imatinib. Treatment of GIST882, GIST430 and GIST48 cells with AT13387 induced HSP70, a marker of HSP90 inhibition, whilst reducing the levels of the client proteins KIT, AKT and their phosphorylated forms. A concomitant decrease in the levels of phospho-ERK and phospho-S6 demonstrated that KIT signaling was being inhibited in all cell lines, whilst an increase in cleaved PARP indicated apoptosis. In contrast, treatment with imatinib inhibited KIT signaling only in the imatinib-sensitive line, GIST882. In vivo, the efficacy of AT13387 was tested in imatinib-sensitive (GIST-PSW) and imatinib-resistant (GIST430) xenograft models. AT13387, dosed once a week, inhibited the growth of both xenografts; depletion of phospho-KIT and inhibition of KIT signaling were again seen in these tumors. As expected, treatment with imatinib caused significant regression of the GIST-PSW tumors but not of GIST430. The combination of imatinib and AT13387 significantly enhanced tumor growth inhibition (T/C 21%) over either of the monotherapies (T/C 30% for AT13387, 46% for imatinib) in the GIST430 xenograft. Importantly, the combination was well tolerated. Conclusions: AT13387 is currently being evaluated in a Phase II GIST trial both as single agent and in combination with imatinib. These results support the potential efficacy of the compound in both imatinib-sensitive and imatinib-resistant GIST and its current testing in this disease. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr A217.

Deregulated AKT signalling is implicated in cancer. The preclinical characterization of AKT inhibitors and development of PD biomarkers are vital prior to clinical trials. Invasive techniques for clinical PD analyses pose ethical and logistical issues, hence hair follicles may represent a non-invasive option. The pyrazole AT7867 and pyrrolopyrimidine CCT128930 are novel ATP-competitive AKT inhibitors from different chemical series developed at The Institute of Cancer Research in collaboration with Astex Therapeutics (Cambridge, UK). AT7867 and CCT128930 have IC50 values against AKT2 of 17nM and 6nM respectively. Growth inhibitory IC50 (GI50) values were 2.4μM and 6.3μM in PTEN-null U87MG glioblastoma cells as measured by SRB assay. Cellular studies of both compounds in U87MG cells were carried out by Meso Scale Discovery (MSD) ELISA, western blot (WB) and immunofluorescence. These showed an initial induction of phosphorylated (p) Ser473 AKT as expected with ATP-competitive AKT inhibitors, and inhibition of downstream AKT targets, including pSer9 GSK-3β, pThr246 PRAS40, pSer127 YAP and pSer235/236 S6RP, indicating AKT pathway blockade. Interestingly, CCT128930 inhibited phosphorylation of AKT targets GSK-3β, S6RP and PRAS40 at lower concentrations (0.5-1µM), compared to AT7867 (5-10µM) in U87MG cells. Phosphorylation was also inhibited at earlier time points with equipotent doses (3XGI50) of CCT128930 versus AT7867. CCT128930 also caused a predominant G0/G1 phase arrest, while AT7867 resulted in a predominant G2 arrest in U87MG cells at equipotent doses (3XGI50), using BrdU and PI staining and flow cytometry. We report for the first time in vivo efficacy with intraperitoneally (ip) or orally administered AT7867 in PTEN-null MES-SA uterine sarcoma and U87MG mouse xenograft models; and ip administered CCT128930 in HER2-overexpressing BT474 breast cancer and U87MG xenografts, which correlated with in vivo pharmacokinetics (PK) and PD biomarker modulation of pSer9 GSK-3β and pSer235/236 S6RP using WB and MSD. Hair follicles were developed as a robust surrogate PD biomarker, with pThr246 PRAS40 as a PD readout. This assay was validated with healthy volunteer hair follicles, which were treated ex vivo with CCT128930. A significant decrease in pThr246 PRAS40 (p In conclusion, by employing an integrated PK and PD biomarker-driven drug discovery strategy, we have developed 2 novel and potent AKT inhibitors with antitumor activity, and have validated a robust surrogate biomarker assay for AKT inhibition for use in clinical trials. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4481.

AT13387 is a novel small molecule inhibitor of HSP90. a member of a family of molecular chaperones. Previously we highlighted an association between the high affinity binding of AT13387 to the N-terminal ATPase domain of HSP90 and the duration of target inhibition in tumor cell lines in vitro. Further, AT13387 was shown to inhibit HSP90 and deplete client proteins in tumor xenografts longer than other, lower affinity inhibitors in the class. Here we have expanded the investigation to a wider number of tumor cell lines and to in vivo xenograft models and demonstrate that AT13387 has an extended pharmacodynamic action in tumors compared to other HSP90 inhibitors. We reason that the cumulative effects of these properties allow for less frequent dosing thus maximising efficacy whilst minimising systemic exposure and the potential for side effects. This study reports extended inhibition of HSP90 by AT13387 in a wider range of tumor cell lines in vitro. A 24hr exposure of A375 (melanoma) cells to AT13387 suppressed the expression of client proteins for 72 hrs or more. However in other cell lines such as NCI-H1975 (lung) and BT474 (breast), the suppression of client proteins by AT13387 was found to last in excess of 7 days. The pharmacodynamic action of AT13387 in vivo has been compared with that of 17-AAG and SNX-5422 in A375 and NCI-H1975 xenografts in nude mice. Following a single dose of each agent, we have investigated and compared the time course of the suppression of levels of several client proteins (e.g. AKT, CDK4) and the phosphorylation of key growth/survival signalling components (e.g. pERK, pS6, pAKT). These effects were rapidly induced in tumors following treatment with AT13387 and levels remained suppressed for up to 96 hrs. The durability of the AT13387 effects was significantly greater than for the other competitor compounds. Investigation of tumor growth in these models demonstrated that the longer pharmacodynamic action of AT13387 ensured that efficacy could be maintained on a once weekly schedule, whereas such a schedule for the other agents resulted in a significant loss of their anti-tumor effects. These data provide further support for the potential benefit of long acting HSP90 inhibitors as a way of maintaining anti-tumor effects whilst minimising potential for undesirable effects associated with systemic exposure. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A217.