Risk Factors for Early Treatment Discontinuation Due to Toxicity Among Patients With Metastatic Castration-resistant Prostate Cancer Receiving Androgen Receptor-targeted Therapy

OBJECTIVES

Androgen receptor-targeted therapies (ARTs) improve survival outcomes in patients with metastatic castration-resistant prostate cancer (mCRPC); however, a significant portion of patients discontinue treatment for various reasons including treatment-related toxicity. We aim to describe reasons for ART treatment discontinuation and identify predictors associated with increased risk of treatment discontinuation due to toxicity.

METHODS

We performed a single-institution retrospective review of patients with mCRPC receiving ART between 2010 and 2021. Our primary aim was to identify risk factors for treatment discontinuation due to toxicity. Our secondary aim was to describe ART discontinuation patterns among patients with mCRPC.

RESULTS

One hundred thirty-three patients with mCRPC started and discontinued ARTs. Fourteen patients (10.5%) discontinued treatment due to toxicity. Common reasons for treatment discontinuation include Prostate Specific Antigen test progression, radiographic progression, toxicity, and death. Significant predictors of treatment discontinuation due to toxicity on bivariate analysis and multivariate analysis included patient-reported falls (odds ratio [OR]: 7.67, CI: [1.31-40.42]; P =0.016), rash (OR: 13.4, CI: [1.35-134.81]; P =0.026), and weakness (OR: 4.16, CI: [1.15-15.0]; P =0.019).

CONCLUSIONS

Our work presents the first description of ART treatment discontinuation and its causes in the real-world setting, as well as patient-reported side effects. Most patients with mCRPC discontinued treatment due to the progression of disease and a minority of patients discontinued secondary to treatment toxicity. Initial multivariable analysis suggests that patient-reported weakness, falls, and rash were associated with a higher likelihood of treatment discontinuation due to toxicity. Early monitoring of this population can prolong the duration of treatment and prevent unnecessary treatment burden.

Assessment of salivary cortisol dynamics in an infantry training exercise: a pilot study

INTRODUCTION

Measuring cortisol during military training offers insights into physiological responses to stress. We attempted precisely timed, cortisol awakening response (CAR) and pre-sleep cortisol (PSC), and diurnal slope (peak morning minus evening cortisol), during a British Army exercise. We aimed to understand cortisol dynamics and evaluate the feasibility of CAR and PSC in this environment.

METHOD

Setting: high-intensity, 10-day infantry exercise. Participants: regular infantry soldiers exercising (EX, n=25) or headquarters-based (HQ, n=6). Participants undertook PSC and WAKE and WAKE+30 min samples after 1-2 days, 5-6 days and 9-10 days. Wrist-worn GENEActiv accelerometers were used to assess sleep duration in EX only. Samples taken ±15 min from prespecified time points were deemed adherent. Validated questionnaires were used to measure resilience and perceived stress. Cortisol and cortisone were measured simultaneously by liquid chromatography tandem mass spectrometry.

RESULTS

From adherent participants' samples, CAR was positive and tended to decrease as the exercise progressed. From all available data, HQ demonstrated greater diurnal slope than EX (F=7.68, p=0.02), reflecting higher morning cortisol (F=4.72, p=0.038) and lower PSC (p=0.04). No differences were seen in cortisol:cortisone ratio. 26.1% of CAR samples were adherent, with moderately strong associations between adherence and stress (r=0.41, p=0.009) but no association between adherence and day of exercise (χ2=0.27, p=0.8), sleep duration (r=-0.112, p=0.43) or resilience (r=-0.79, p=0.75). Test-retest reliability ratings for CAR were Cronbach's α of 0.48, -11.7 and 0.34 for the beginning, middle and end of the exercise, respectively.

CONCLUSIONS

We observed a reduction in morning cortisol and decreased diurnal slope during a high-intensity military exercise, compared with the HQ comparator cohort in whom diurnal slope was preserved. A carefully timed CAR was not feasible in this setting.

Telehealth follow-up consultations for melanoma patients during the COVID-19 pandemic: Patient and clinician satisfaction

INTRODUCTION

The COVID-19 pandemic caused rapid implementation of telehealth for melanoma follow-up care in Australia. This study explores Australian melanoma patients and clinicians' level of satisfaction with telehealth.

METHODS

A cross-sectional study was conducted across three specialist melanoma centres in Sydney, Australia. Melanoma patients (all stages) and clinicians completed mixed methods surveys seeking socio-demographic and clinical information and questionnaires to assess satisfaction with telehealth. Additionally, patients completed measures of quality of life, fear of cancer recurrence and trust in their oncologist. Patients and clinicians provided open-ended responses to qualitative questions about their perceptions of telehealth.

RESULTS

One hundred and fifteen patients and 13 clinicians responded to surveys. Telephone was used by 109 (95%) patients and 11 (85%) clinicians. Fifty-seven (50%) patients and nine (69%) clinicians preferred face-to-face consultations, 38 (33%) patients and 3 (23%) clinicians preferred a combination of face-to-face and telehealth consultations. Five (4%) patients and nil clinicians preferred telehealth consultations. Patients diagnosed with early-stage melanoma, using telehealth for the first time, who have lower trust in their oncologist, and having higher care delivery, communication and supportive care concerns were likely to report lower satisfaction with telehealth. Open-ended responses were consistent between patients and clinicians, who reported safety, convenience and improved access to care as major benefits, while identifying personal, interpersonal, clinical and system-related disadvantages.

DISCUSSION

While telehealth has been widely implemented during COVID-19, the benefits identified by patients and clinicians may extend past the pandemic. Telehealth may be considered for use in conjunction with face-to-face consultations to provide melanoma follow-up care.

Developing a multimodal biosensor for remote physiological monitoring

INTRODUCTION

Several UK military expeditions have successfully used physiological sensors to monitor participant's physiological responses to challenging environmental conditions. This article describes the development and trial of a multimodal wearable biosensor that was used during the first all-female unassisted ski crossing of the Antarctic land mass. The project successfully transmitted remote real-time physiological data back to the UK. The ergonomic and technical lessons identified have informed recommendations for future wearable devices.

METHOD

The biosensor devices were designed to be continuously worn against the skin and capture: HR, ECG, body surface temperature, bioimpedance, perspiration pH, sodium, lactate and glucose. The data were transmitted from the devices to an android smartphone using near-field technology. A custom-built App running on an android smartphone managed the secure transmission of the data to a UK research centre, using a commercially available satellite transceiver.

RESULTS

Real-time physiological data, captured by the multimodal device, was successfully transmitted back to a UK research control centre on 6 occasions. Postexpedition feedback from the participants has contributed to the ergonomic and technical refinement of the next generation of devices.

CONCLUSION

The future success of wearable technologies lies in establishing clinical confidence in the quality of the measured data and the accurate interpretation of those data in the context of the individual, the environment and activity being undertaken. In the near future, wearable physiological monitoring could improve point-of-care diagnostic accuracy and inform critical medical and command decisions.

Risk factors for treatment (tx) toxicity and discontinuation among patients (pts) with metastatic castration-resistant prostate cancer (mCRPC) on androgen receptor targeted therapy (ART)

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Background: mCRPC is associated with (a/w) increased mortality among prostate cancer pts and new and safe txs are needed. In recent clinical trials, ARTs improved survival outcomes within this population, however, a significant portion will go on to discontinue tx. We aim to describe reasons for ART tx discontinuation and to identify predictors a/w increased risk of tx discontinuation due to tx toxicity or death. Methods: We performed a single-institution retrospective review of mCRPC pts on ART between 2010 and 2021. We screened for demographics, medical history, ART course, and tx side-effects. Our primary aim was to identify risk factors for tx discontinuation due to toxicity or death. Our secondary aim was to describe ART discontinuation among mCRPC. Fisher’s Exact was used to identify significant predictors of tx discontinuation due to toxicity or death. Significant outcomes were included in a multivariate logistic regression to determine odds ratios. Results: 133 pts with mCRPC started and discontinued ARTs. Among this cohort, 27 pts (20.3%) discontinued tx due to death or toxicity. Reasons for tx discontinuation are described in the table below. Significant predictors of tx discontinuation due to toxicity or death on bivariate analysis included pt-reported sepsis, hypertension (htn), weakness, falls, ECOG ≥2, and hospitalization during tx. Adjusting for confounders, pt-reported falls (OR 2.35; [0.91-2.59]; p=0.009), htn (OR 2.06; [0.94-2.21]; p=0.027), and weakness (OR 1.63; [0.59-2.72]; p=0.007) were a/w an increased risk of pt tx discontinuation from toxicity or death. Conclusions: Our results illustrate that the majority of mCRPC pts discontinued tx due to progression of disease. The data also indicates that mCRPC pts reporting new onset htn, falls, or weakness were more likely to discontinue tx due to toxicity or death. Early monitoring of this population is warranted to prolong duration of tx and prevent unnecessary txs. [Table: see text]

Clinical characteristics and outcomes of trial-ineligible patients (pts) with metastatic castration-resistant prostate cancer (mCRPC) receiving androgen receptor targeted (ART) therapy

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Background: mCRPC pts with significant comorbidities or poor performance status (PS) are often excluded from clinical trials for ART. These cohorts may not be representative of or comparable to real-world pts. We aimed to determine whether (1) baseline characteristics or (2) survival outcomes differed in pts with mCRPC categorized as eligible or ineligible for ART clinical trials. Methods: We screened for pts with mCRPC treated with abiraterone (abi-) or enzalutamide (enza-) at our institution between 2010 and 2021. Baseline characteristics were reviewed at treatment start and ART course recorded. We applied the inclusion/exclusion criteria from clinical trials, COU-AA-301, COU-AA-302, PREVAIL, and AFFIRM, to categorize pts as ineligible or eligible. Fischer’s exact was used to evaluate pt characteristics. Cox proportional hazards model was used to compare survival outcomes. Results: We identified 150 pts with mCRPC who initiated abi- or enza-. 54.7% of pts were deemed trial ineligible. Among pts on abi-, 48 of 86 (55.8%) pts were ineligible. Among those on enza-, 34 of 64 (53.1%) were ineligible. Common reasons for ineligibility included poor PS, radiation during treatment, and trial specific comorbidities. Among ineligible pts, 11% were post-chemotherapy compared to 20.6% of eligible pts (p = .162). Notably, trial ineligible pts were more likely to be non-Hispanic black when compared to trial eligible pts (29.3% vs. 17.6%, p = 0.036). Median OS was 30.2 for ineligible pts and 37.1 for eligible pts p = 0.46). for the ineligible pts and eligible pts respectively and there was no significant difference on univariate or multivariate analyses (HR: 0.84 [0.54, 1.32;]. Conclusions: Pts classified as trial ineligible had comparable survival outcomes when compared to trial eligible pts. Consistent with prior research on systemic racism in clinical trials, ineligible pts were more likely to identify as Black compared to eligible pts. Further research is warranted to confirm safety of ART in ineligible pts and identify strategies for reducing racial disparity gaps in cancer clinical trials.

Survival outcomes and toxicity in older adults with metastatic castration-resistant prostate cancer (mCRPC) treated with androgen receptor targeted (ART) therapies

117

Background: Prostate cancer (PCa) and especially advanced PCa largely affects older adults with a median age of diagnosis of 67. Despite ART’s role as a mainstay of treatment (tx) in advanced PCa, little is known about its risks/benefits in older adults. We aimed to examine survival outcomes and safety in patients (pts) with mCRPC ≥75 years-old (y.o) on ART. Methods: The records of mCRPC pts treated with ART at the Mount Sinai Hospital between 2010 and 2021 were screened for demographics, medical history, ART course, tx toxicity, and survival outcomes. PSA progression free survival (PFS) between pts ≥75 y.o and pts ≤75 y.o was assessed as the primary outcome. Secondary outcomes were overall survival (os) and tx toxicity. Tx toxicity was evaluated using physician documented tx side-effects (SE)s. Fischer’s exact was used to compare baseline characteristics and tx SEs. Cox proportional hazards models were used to compare survival outcomes. Results: Of 153 pts, 97 were < 75 y.o and 56 were ≥75 y.o. Within the <75 y.o group, 17 (17.5%) were post-chemo compared to 7 (12.5%) in the ≥75 group (p = .493) Relevant baseline characteristics (ECOG ≥2, Race, Gleason 4-5, hospitalizations, and CCI) were not significantly different. Median PSA PFS was 14.2 (≥75 y.o) and 17.3 months (<75 y.o) with no significant difference on univariate or multivariate analysis (HR: 1.1 [0.69, 1.74;] p = 0.697. Median OS was 32.4 months for the ≥75 y.o cohort and 32.3 months for the <75 y.o cohort (HR: 1.38 [0.88, 2.17;] p = 0.156). The 5 most common SEs by group are reported below. Of note, adults ≥75 y.o were more likely to report edema compared to the <75 y.o pts (8.2% vs 21.4%, p-value = .026). Conclusions: Pts ≥75 on ART experienced similar survival benefits compared with pts <75. While older adults were more likely to report edema, overall tx toxicity profiles did not differ significantly. Ultimately, these findings ground evidence-based counseling and tx for older adults with mCRPC considering ART. [Table: see text]

The effect of statin use on survival outcomes in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with androgen receptor targeted therapies (ART)

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Background: Statins may reinforce and provide a compounded effect on ART by decreasing cholesterol levels thus decreasing de novo androgen synthesis. We aim to investigate the clinical effect of concurrent statin and ART use on outcomes of mCRPC patients. Methods: We conducted a retrospective analysis on mCRPC patients receiving ART from a single institution. Relevant demographic and clinical data was collected in addition to ART treatment course, statin treatment, and survival outcomes. Our primary outcome was PSA progression free survival (PFS) and our secondary outcomes were overall survival (OS) and associated prognostic factors for both PSA PFS and OS. Chi-squared test and Wilcoxon signed ranked test were used to compare baseline characteristics, and a Cox proportional hazards regression model was used to estimate hazard ratios (HR) with 95% confidence interval (CI) for overall survival (OS) and PSA PFS. Results: 153 patients were included in the analysis between 2010 and 2021. 67 patients (mean age 73.8 years) received concurrent statins and 86 patients (mean age 67.6 years) did not. Median PSA PFS was 37.4 months for patients that received concurrent statins and 17.4 months for patients that did not receive statins. On univariate and multivariate analyses, there was no statistically significance difference between groups for PSA PFS (HR 0.7; CI 0.44-1.1; p=0.122). Median OS was 35.6 months for patients that received concurrent statins and 24.0 months for patients who did not. There was no statistical significance between groups for OS on univariate or multivariate analyses (HR 0.67; CI 0.42-1.06; p=0.087). Conclusions: Although results were not statistically significant, our study illustrates that concurrent statin use exhibits improved time to PSA progression and OS in mCRPC patients. Larger multi-center and further prospective studies are warranted to elucidate the relationship between statin use and overall outcomes in this population.

Sex, gender or occupational psychology: what matters most to preventing heat-related illnesses and improving outcomes for women in ground close combat?

Since the advent of women in ground close combat (WGCC) roles, the impact on women of the attendant risk of heat stress and heat illness has been considered. Much emphasis has been placed on sex differences in thermal physiology. This article considers the application of evidence of sex-associated thermoregulatory variation to the occupational and environmental setting of WGCC, and weighs the relative importance of physiological differences arising from biological sex, and behaviour associated with gender normatives. Quantifying the risk of heat illness to WGCC should draw on data from their real-world occupational context.

Does physical activity mediate the associations between blue space and mental health? A cross-sectional study in Australia

BACKGROUND

Research has begun to examine whether blue space is beneficial to mental health. While results are promising, it is difficult to know which aspects of mental health or mental ill-health may benefit most. Physical activity has been proposed as one potential mechanism via which blue space may be associated with better mental health. However, very few studies have examined mechanisms. We examined associations between blue space proximity and a range of mental health outcomes and examined which of these associations were mediated by physical activity.

METHODS

350 participants (M = 38.74, SD = 14.92, 70% female) self-reported their weekly physical activity and completed measures of depression, anxiety, and psychological wellbeing. We then used GIS software to calculate blue space proximity (i.e., coastal and inland), and structural equation modelling with mediation paths to determine the role of physical activity in the associations between bluespace and mental health.

RESULTS

Physical activity partially mediated the associations between coastal proximity and depression (β = 0.02, 95% CI = 0.001, 0.05), anxiety (β = 0.03, 95% CI = 0.01, 0.06), and wellbeing (β = - 0.03, 95% CI = - 0.08, - 0.01), and fully mediated the associations between inland water proximity and depression (β = 0.02, 95% CI = 0.003, 0.05), anxiety (β = 0.03, 95% CI = 0.01, 0.07), and wellbeing (β = - 0.03, 95% CI = - 0.07, - 0.01).

CONCLUSION

While physical activity appears to explain associations between inland blue space and mental health outcomes, it only partially explains the association between coastal blue space and mental health, suggesting other mechanisms may play a role and even inactive exposure may be beneficial.

Perspectives of postdoctoral fellows: A qualitative study of clinical supervision in psycho-oncology

Given the prevalence and distress associated with a cancer diagnosis, the training of psycho-oncology providers to meet the mental health needs of cancer survivors warrants investigation. Clinical supervision is a key teaching strategy for psychology trainees, particularly during a postdoctoral fellowship when trainees are gaining specialized training and making important career decisions. This qualitative study examined how postdoctoral fellows in psycho-oncology used clinical supervision and the supervisory relationship for their personal and professional development. Interviews were conducted with 10 postdoctoral trainees in the United States; data were analyzed using consensual qualitative research methodology. Five themes emerged from the data: supervisees' learning experiences in supervision, foundations and features of support derived from supervision, ethical and social issues, unmet needs in current supervision, and strategies to enhance future supervision. Supervision was a space to learn about leadership and supervisory skills, professional identity, career preferences, multidisciplinary teamwork, knowledge about cancer, emotional responses, self-care practices, ethical dilemmas, social and cultural issues, and power dynamics. Participants also shared needs that were not met in supervision, which included both missed content (e.g., professional development issues and clinical concerns) and constraints of the supervisory relationship. Drawing on the study findings, recommendations are made to enhance the supervisory relationship for both trainees and supervisors in psycho-oncology and to ensure clinicians can thrive while competently and compassionately working with cancer survivors. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

NKG2A and HLA-E define an alternative immune checkpoint axis in bladder cancer

Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1)-blockade immunotherapies have limited efficacy in the treatment of bladder cancer. Here, we show that NKG2A associates with improved survival and responsiveness to PD-L1 blockade immunotherapy in bladder tumors that have high abundance of CD8+ T cells. In bladder tumors, NKG2A is acquired on CD8+ T cells later than PD-1 as well as other well-established immune checkpoints. NKG2A+ PD-1+ CD8+ T cells diverge from classically defined exhausted T cells through their ability to react to human leukocyte antigen (HLA) class I-deficient tumors using T cell receptor (TCR)-independent innate-like mechanisms. HLA-ABC expression by bladder tumors is progressively diminished as disease progresses, framing the importance of targeting TCR-independent anti-tumor functions. Notably, NKG2A+ CD8+ T cells are inhibited when HLA-E is expressed by tumors and partly restored upon NKG2A blockade in an HLA-E-dependent manner. Overall, our study provides a framework for subsequent clinical trials combining NKG2A blockade with other T cell-targeted immunotherapies, where tumors express higher levels of HLA-E.

From Bench to Bedside: How the Tumor Microenvironment Is Impacting the Future of Immunotherapy for Renal Cell Carcinoma

Immunotherapy has revolutionized the treatment landscape for many cancer types. The treatment for renal cell carcinoma (RCC) has especially evolved in recent years, from cytokine-based immunotherapies to immune checkpoint inhibitors. Although clinical benefit from immunotherapy is limited to a subset of patients, many combination-based approaches have led to improved outcomes. The success of such approaches is a direct result of the tumor immunology knowledge accrued regarding the RCC microenvironment, which, while highly immunogenic, demonstrates many unique characteristics. Ongoing translational work has elucidated some of the mechanisms of response, as well as primary and secondary resistance, to immunotherapy. Here, we provide a comprehensive review of the RCC immunophenotype with a specific focus on how preclinical and clinical data are shaping the future of immunotherapy.

Development of a psychosocial oncology core curriculum for multidisciplinary education and training: Initial content validation using the modified Delphi Method

OBJECTIVE

Despite its four decade history, the multidisciplinary specialty of psychosocial oncology (PSO) has no official consensus on core content. In 2014, the American Psychosocial Oncology Society (APOS) Board charged the APOS Professional Education Committee with outlining curricular content needed for core competence.

METHODS

Content validation was completed using a four-phase modified Delphi Method. During Phase I, a Professional Education Committee subgroup proposed domains and items, which were rated by the APOS Fellows and Board via online survey. During Phase II, Fellows completed a second, revised survey. Phase III incorporated early career members. Developmental and diversity items were integrated into each domain. In Phase IV, a larger group of subject matter experts were surveyed, with feedback incorporated. Validation across phases involved average rating thresholds, intraclass correlations, and final percent agreement.

RESULTS

The Delphi Method supported 12 content domains: Cancer Basics, Psychosocial Oncology, Professional Development, Ethics, Emotional/Psychological Concerns, Sexuality and Relationship Concerns, Spiritual/Religious Concerns, Healthcare Communication and Decision Making, Social/Practical Problems, Caregiver Concerns, Cognitive Concerns, Physical Symptoms and Psychosocial Assessment/Treatment. High levels of agreement were achieved across domains (86%-100%) and items, with no significant rating differences by discipline.

CONCLUSIONS

This proposed core content can enhance and standardize education and training in PSO including APOS' Virtual Psychosocial Oncology Core Curriculum, focused on broadly expanding the PSO workforce, particularly in underserved areas. Next steps include development of core competencies and establishment of online training modules based on this content validation.

CPD in the remote environment: a role for practice-based small group learning

BACKGROUND

Continuous professional development (CPD) is recognised as essential and mandated by the Royal College of General Practitioners and other medical professional colleges. However, it can be difficult to maintain when deployed and remote from normal training and support structures. There is no literature directly discussing how military doctors in the deployed and remote environment maintain CPD and if practice-based small group learning (PBSGL) could be an appropriate tool to facilitate this in future.

AIM

To describe the CPD experience of medical officers (MOs) working for the Defence Medical Services (DMS) and assess if offering PBSGL would be welcomed and likely beneficial.

DESIGN AND SETTING

This is a quantitative survey of doctors working in primary care within the DMS.

METHOD

A questionnaire was designed to elicit opinions, current practice and previous experience of CPD within the deployed and firm base environments. It also aimed to elicit prior experience of and appetite for PBSGL as a solution. This was then distributed via email to MOs working for the DMS.

RESULTS

130 responses (25%) were received. 122 (96%) had heard of PBSGL, 56% had participated in PBSGL in the firm base. 60% agreed or strongly agreed PBSGL was an effective way to maintain CPD. 73% reported eLearning as a mode of maintaining CPD while deployed or working in a remote environment.

CONCLUSION

This study demonstrated that many general practitioners deployed to remote locations feel that CPD provision could be improved and that PBSGL is a potential solution.

Social Isolation Among Older Adults in Long-Term Care: A Scoping Review

Objectives: A wealth of literature has established risk factors for social isolation among older people; however, much of this research has focused on community-dwelling populations. Relatively little is known about how risk of social isolation is experienced among those living in long-term care (LTC) homes. We conducted a scoping review to identify possible risk factors for social isolation among older adults living in LTC homes. Methods: A systematic search of five online databases retrieved 1535 unique articles. Eight studies met the inclusion criteria. Results: Thematic analyses revealed that possible risk factors exist at three levels: individual (e.g., communication barriers), systems (e.g., location of LTC facility), and structural factors (e.g., discrimination). Discussion: Our review identified several risk factors for social isolation that have been previously documented in literature, in addition to several risks that may be unique to those living in LTC homes. Results highlight several scholarly and practical implications.

Uncialamycin-based antibody-drug conjugates: Unique enediyne ADCs exhibiting bystander killing effect

Antibody-drug conjugates (ADCs) have emerged as valuable targeted anticancer therapeutics with at least 11 approved therapies and over 80 advancing through clinical trials. Enediyne DNA-damaging payloads represented by the flagship of this family of antitumor agents, N-acetyl calicheamicin [Formula: see text], have a proven success track record. However, they pose a significant synthetic challenge in the development and optimization of linker drugs. We have recently reported a streamlined total synthesis of uncialamycin, another representative of the enediyne class of compounds, with compelling synthetic accessibility. Here we report the synthesis and evaluation of uncialamycin ADCs featuring a variety of cleavable and noncleavable linkers. We have discovered that uncialamycin ADCs display a strong bystander killing effect and are highly selective and cytotoxic in vitro and in vivo.

Design, Synthesis, and Biological Evaluation of Tubulysin Analogues, Linker-Drugs, and Antibody-Drug Conjugates, Insights into Structure-Activity Relationships, and Tubulysin-Tubulin Binding Derived from X-ray Crystallographic Analysis

Molecular design, synthesis, and biological evaluation of tubulysin analogues, linker-drugs, and antibody-drug conjugates are described. Among the new discoveries reported is the identification of new potent analogues within the tubulysin family that carry a C11 alkyl ether substituent, rather than the usual ester structural motif at that position, a fact that endows the former with higher plasma stability than that of the latter. Also described herein are X-ray crystallographic analysis studies of two tubulin-tubulysin complexes formed within the α/β interface between two tubulin heterodimers and two highly potent tubulysin analogues, one of which exhibited a different binding mode to the one previously reported for tubulysin M. The X-ray crystallographic analysis-derived new insights into the binding modes of these tubulysin analogues explain their potencies and provide inspiration for further design, synthesis, and biological investigations within this class of antitumor agents. A number of these analogues were conjugated as payloads with appropriate linkers at different sites allowing their attachment onto targeting antibodies for cancer therapies. A number of such antibody-drug conjugates were constructed and tested, both in vivo and in vitro, leading to the identification of at least one promising ADC (Herceptin-LD3), warranting further investigations.

Comparative compositional analysis of cassava brown streak disease resistant 4046 cassava and its non-transgenic parental cultivar

Compositional analysis is an important component of an integrated comparative approach to assessing the food and feed safety of new crops developed using biotechnology. As part of the safety assessment of cassava brown streak disease resistant 4046 cassava, a comprehensive assessment of proximates, minerals, amino acids, fatty acids, vitamins, anti-nutrients, and secondary metabolites was performed on leaf and storage root samples of 4046 cassava and its non-transgenic parental control, TME 204, collected from confined field trials in Kenya and Uganda over two successive cropping cycles. Among the 100 compositional components that were assessed in samples of 4046 and control TME 204 cassava roots (47 components) and leaves (53 components), there were no nutritionally relevant differences noted. Although there were statistically significant differences between the transgenic and control samples for some parameters, in most cases the magnitudes of these differences were small (<20%), and in every case where comparative literature data were available, the mean values for 4046 and control cassava samples were within the range of normal variation reported for the compositional component in question. Overall, no consistent patterns emerged to suggest that biologically meaningful adverse changes in the composition or nutritive value of the leaves or storage roots occurred as an unintended or unexpected consequence of the genetic modification resulting in 4046 cassava. The data presented here provide convincing evidence of the safety of 4046 cassava with respect to its biochemical composition for food and feed, and it could be considered as safe as its non-transgenic control.

0802 To Examine the Effect of Gabapentin Enacarbil in Primary Restless Legs Syndrome Patients Who are on Dopaminergic Agents and Exhibiting Augmentation

Introduction

Augmentation is defined as worsening of the symptoms of Restless Legs Syndrome after a brief period of initial improvement with dopaminergic agents resulting in either an earlier onset, increase in severity, quicker onset, spread to other body parts. The exact prevalence of this phenomenon is not known and in patients experiencing augmentation, it can pose a difficult diagnostic and therapeutic challenge to the clinician. In our study, we found extended-release gabapentin to be an effective intervention in patients experiencing dopaminergic augmentation

Methods

This is an open-label single-arm study done in patients exhibiting augmentation while on dopaminergic agents. Patients who were enrolled in the study were initiated on oral extended-release gabapentin(Horizont) 600 mg at 5 pm at the beginning of the study. At day 90, attempts were made to reduce or discontinue dopaminergic agents. International Restless Legs Syndrome-Rating Scale (IRLS) and Augmentation Severity Rating Scale(ASRS) were recorded at each visit.

Results

A total of 10 patients were enrolled in the study while only 8 patients completed it. Compared to the baseline (visit 2), there is a significant improvement in both the augmentation severity(p= 0.0131) and the IRLS (p=0.0497). Wilcoxon matched-pairs signed rank test was used for statistical analysis.

Conclusion

Extended-release Gabapentin is an effective treatment option in primary RLS patients experiencing augmentation secondary to dopaminergic medication usage.

Support

The study is funded and medication is provided by Arbor Pharmaceuticals.

The development and evaluation of a nationwide training program for oncology health professionals in the provision of genetic testing for ovarian cancer patients

BACKGROUND

BRCA1/2 mutation status has increasing relevance for ovarian cancer treatments, making traditional coordination of genetic testing by genetic services unsustainable. Consequently alternative models of genetic testing have been developed to improve testing at the initial diagnosis for all eligible women.

METHODS

A training module to enable mainstreamed genetic testing by oncology healthcare professionals was developed by genetic health professionals. Oncology healthcare professionals completed questionnaires before and 12 months post-training to assess perceived skills, competence and barriers to their coordinating genetic testing for women with high-grade non-mucinous epithelial ovarian cancer. Genetic health professionals were surveyed 12 months post-training to assess perceived barriers to implementation of mainstreaming.

RESULTS

185 oncology healthcare professionals were trained in 42 workshops at 35 Australasian hospitals. Of the 273 tests ordered by oncology healthcare professionals post-training, 241 (93.1%) met national testing guidelines. The number of tests ordered by genetic health professionals reduced significantly (z = 45.0, p = 0.008). Oncology healthcare professionals' perceived barriers to mainstreamed testing decreased from baseline to follow-up (t = 2.39, p = 0.023), particularly perceived skills, knowledge and attitudes. However, only 58% reported either 'always' or 'nearly always' having ordered BRCA testing for eligible patients at 12 months, suggesting oncology healthcare professionals' perceived barriers were not systematically addressed through training.

CONCLUSIONS

Oncology healthcare professionals have demonstrated a willingness to be involved in the provision of genetic testing in a mainstreaming model. If oncology services are to hold responsibility for coordinating genetic testing, their readiness will require understanding of barriers not addressed by training alone to inform future intervention design.

Heat illness during initial military training

INTRODUCTION

Exertional heat illness (EHI) is recognised as a significant problem for fit young individuals taking part in strenuous activity in temperate climates. The aim of this research was to relate episodes of reported EHI against known risk factors for heat illness and determine whether modification of the training programme had an effect on the number of cases reported. Publication was not possible when the work was originally conducted in 2000 because of barriers within Royal Military Academy Sandhurst (RMAS) at the time.

METHODS

A retrospective study examined the medical data for Officer Cadets in training at the RMAS for a 2-year period ending April 2000.

RESULTS

60 cases were initially reported as EHI, in 58 individuals. Using the following criteria; dizziness, collapse, reduced conscious level, headache, nausea, vomiting, elevated core (rectal) temperature and the results of urine and blood tests, 35 cases were diagnosed as EHI and 25 cases had other diagnoses recorded after investigation. Minority of cases (n=12) had an identifiable risk factor but the majority appeared to be fit young individuals who were susceptible to EHI in conditions where the rest of the population was unaffected.

DISCUSSION

Further work is planned to study individuals during strenuous activity events in the hope of accurately identifying those at risk and further reducing the incidence of EHI. EHI is common, case definition is poor, risk factors are not present in all individuals but modification of training programmes is effective.

Bioelectrochemical remediation of phenanthrene in a microbial fuel cell using an anaerobic consortium enriched from a hydrocarbon-contaminated site

Polycyclic aromatic hydrocarbons (PAH) are organic pollutants that require remediation due to their detrimental impact on human and environmental health. In this study, we used a novel approach of sequestering a model PAH, phenanthrene, onto a solid carbon matrix bioanode in a microbial fuel cell (MFC) to assess its biodegradation coupled with power generation. Here, the bioanode serves as a site for enrichment of electroactive and hydrocarbon-degrading microorganisms, which can simultaneously act to biodegrade a pollutant and generate power. Carbon cloth electrodes loaded with two rates of phenanthrene (2 and 20 mg cm^-2) were compared using dual chamber MFCs that were operated for 50 days. The lower loading rate of 2 mg cm^-2 was most efficient in the degradation of phenanthrene and had higher power production capacities (37 mW m^-2) as compared to the higher loading rate of 20 mg cm^-2 (power production of 19.2 mW m^-2). FTIR (Fourier-Transform Infrared Spectroscopy) analyses showed a depletion in absorbance peak signals associated with phenanthrene. Microbes known to have electroactive properties or phenanthrene biodegradation abilities like Pseudomonas, Rhodococcus, Thauera and Ralstonia were enriched over time in the MFCs, substantiating the electrochemical and FTIR analyses. The MFC approach taken here thus offers great promise towards PAH bioelectroremediation.

Role of the pre-hospital treatment team on the UK military exercise SAIF SAREEA 3

The prehospital treatment team (PHTT) involves a small team working under the clinical supervision of a clinical lead. The clinical lead can be a general duties medical officer (Post Foundation Years Doctor), military nurse practitioner or more senior clinician. The team is mounted in vehicles appropriate to the environment they expect to operate in. A PHTT is closely located to the front line reducing transportation timelines from the point of wounding to more definitive care. The PHTT can provide medical support on the move or when time is available; a more permanent fully erected treatment facility can be established. Either configuration can provide both trauma and primary care. The size of the team allows for multiple trauma subteams enabling care to casualties that arrive simultaneously. The PHTT can move independently which could leave the team vulnerable as there is no integral force protection within the current structure. In such a small team, the right balance of medical and soldiering skills among team members is essential to success. Exercise SAIF SAREEA 3 represented a large-scale battlegroup exercise to the Middle East in the austere desert of Oman. This provided an ideal environment for employing the PHTT concept is a large deployed force undertaking dynamic activity.

Elevated circulating CCL2 in prostate cancer patients

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Background: Monocyte chemoattractant protein 1 (CCL2 or MCP-1), a chemokine secreted by monocytic cells, is critical in recruiting Treg and MDSCs into the tumor microenvironment and in regulating prostate cancer (PCa) migration and proliferation. In this study, we examined circulating CCL2 levels in healthy vs PCa patients and used an in vitro coculture model to identify the source of the elevated CCL2. Methods: Serum CCL2 concentrations were evaluated via ELISA in 59 patients (19 health controls, 20 “treatment naïve” PCa, 20 mCRPC). Monocytic leukemia cells (U937) were either directly cocultured with PC3 PCa cell line or cultured in the PC3 conditioned medium (CM). The induction of CCL2 mRNA in the cultures was examined by qPCR. The secretion of CCL2 into cell culture supernatants was evaluated via human cytokine array. Neutralizing antibodies to several overexpressed inflammatory cytokines in PC3 cells were added into the PC3 CM to evaluate the contribution of these inflammatory cytokines to CCL2 induction. Results: Circulating CCL2 concentrations were significantly higher in prostate cancer patient serum compared to control patient serum (p=4.4e-6) (Table). To understand the potential source of elevated CCL2, we grew U937 and PC3 in coculture and evaluated with qPCR, revealing that while CCL2 was not expressed in PC3 cells, it was expressed at very low levels in U937 cells. Interestingly, coculture of PC3 with U937 increased CCL2 mRNA expression by over 10-fold, and the result was confirmed at protein levels by human cytokine array. Our results also indicated that IL-6 and GM-SCF were the two major cytokines released by PCa cells to induce CCL2 mRNA in U937 cells and MEK and JAK-STAT signaling were crucial for CCL2 induction. Conclusions: Prostate cancer cells induce CCL2 secretion from monocytes in an IL-6 and GM-CSF dependent manner. Given the critical role of CCL2 in mediating immunosuppressive tumor microenvironments, our study highlighted the CCL2 Concentrations in PCa vs Healthy Serum.[Table: see text]

Publication outcomes of abstracts presented at 2013 North American Congress of Clinical Toxicology (NACCT) conference

Introduction: Scientific conferences are useful in disseminating medical research and advancing the medical and scientific fields. An important measure of the success of such conferences is the proportion of research that is published in peer-reviewed journals. The conversion rates for toxicology abstracts to full-text publications at previous North American toxicology meetings were low. No study has assessed the publication rate from the 2013 North American Congress of Clinical Toxicology (NACCT) conference.Methods: We reviewed 316 abstracts presented at the 2013 NACCT Conference. We searched the PubMed, EMBASE, and Medline databases using the authors' names and keywords, through September 2019. We then identified and excluded cases and case reports to reanalyze the data.Results: Thirty-three of 316 abstracts (10.4%) subsequently appeared in 17 different peer-reviewed journals, led by Clinical Toxicology (13 out of 33, 3%). Leading countries of origin for abstract submission were the USA (285), Canada (9), and the UK (8). Excluding case reports, 25 out of 207 abstracts (12.0%) achieved publication in peer-reviewed journals.Conclusions: Fewer than one in eight abstracts reached publication within six years of the 2013 NACCT meeting, even after accounting for and excluding case reports. This rate is lower than in other specialty medical societies.

Dietary intake in cystic fibrosis and its role in glucose metabolism

BACKGROUND

Dietary intervention in cystic fibrosis (CF) has historically focused on high-energy diets to address malnutrition, with little attention on diet quality. With increased survival, CF complications such as impaired glucose tolerance (IGT) and cystic fibrosis related diabetes (CFRD) have increased in prevalence. In the absence of consensus on the management of IGT, the role of dietary intake, specifically carbohydrate quality, requires consideration.

AIMS

The aims of this study were to: 1) determine nutritional quality of dietary intake at an adult CF clinic and compare this to the Australian Dietary Guidelines 2) explore relationships between dietary intake, including glycaemic index (GI) and glycaemic load (GL), and glucose response variables using continuous glucose monitoring (CGM).

METHODS

Adults attending a Sydney hospital were recruited to undergo CGM for five-seven days and record dietary intake using a food record over the CGM period. The relationship between variables of dietary intake, including GI and GL and variables of glycaemic response, including mean amplitude of glycaemic excursions (MAGE), percentage of time in hyperglycaemic and euglycaemic range, were determined.

RESULTS

Eighteen participants completed the study with 87 full days of dietary and CGM data. Dietary intake was higher than recommendations in the Australian Dietary Guidelines in relation to grains and protein foods and only slightly higher in saturated fat. Bivariate correlations showed dietary GI was significantly positively associated with percentage of time in hyperglycaemic range. Dietary GL was significantly associated with SD, MAGE and percentage of time in euglycaemic range on CGM. Results remained significant when controlled for energy intake in partial correlation analyses.

CONCLUSIONS

This study suggests GI and GL may be important dietary factors influencing glucose metabolism in CF. Further studies exploring low GI or GL diets as a dietary intervention in CF are the next step.

The Effect of Employee Engagement on Organizational Citizenship Behaviour: An Empirical Study on an Egyptian University

The goal of the study is to examine the effect of Employee Engagement (EE) as an independent variable on Organizational Citizenship Behaviour (OCB) as a dependent variable. The study was carried out in an Egyptian public university (Ain Shams University). The data was collected through questionnaires distributed to faculty members. The sample consisted of 318 questionnaires valid for statistical analysis. The methodology used was regression analysis, and structured equation model (path analysis). The study found a positive direct effect of  EE on OCB.

Liquid buccal mucosa graft endoscopic urethroplasty: a validation animal study

PURPOSE

To validate a novel method of urethral stricture treatment using liquid buccal mucosal grafts (LBMG) to augment direct vision internal urethrotomy (DVIU) in an animal model.

MATERIALS AND METHODS

A rabbit stricture model was used to test this method. Strictures were induced in 26 rabbits using electroresection of urethral epithelium. The animals were randomized into two groups: Group-1, treated with DVIU and LBMG in fibrin glue, and Group-2, DVIU with fibrin glue only. LBMG was prepared by suspension of mechanically minced buccal mucosa micrografts in fibrin glue. This LBMG-fibrin glue mixture was later injected into the urethrotomies of Group-1 animals. All animals were killed at 24 weeks after repeat retrograde urethrogram (RUG) and urethroscopy by surgeon blinded to the treatment arm. Radiographic images and histological specimens were reviewed by a radiologist and a pathologist, respectively, blinded to the treatment arm. Stricture treatment was considered a success if a diameter measured on RUG increased by ≥ 50% compared to pre-treatment RUG diameter. Histological specimens were assessed for the presence of BMG engraftment.

RESULTS

In Group-1, 8/12(67%) animals demonstrated engraftment of LBMG, compared to none in Group-2 (p = 0.0005). 7/12(58%) in Group-1 showed radiographic resolution/improvement of strictures compared to 5/13 Group-2 rabbits (38%, p = 0.145). The median percent change for the Group-1 was 59%, compared to 41.6% for Group-2 (p = 0.29).

CONCLUSION

This proof-of-concept study demonstrates feasibility of LBMG for endoscopic urethral stricture repairs. Further studies are needed to establish the role of this novel concept in treatment of urethral strictures.

Family history of prostate cancer and age-related trend of testosterone levels among US males: NHANES 2003-2004

BACKGROUND

Studies have suggested that rapid age-related declines of testosterone (T) level may play a critical role in the development of prostate cancer (PCa), and family history of PCa is another well-established risk factor of PCa, which have been reported to be associated with androgen metabolism-related genes. However, few studies have ever investigated whether a family history of PCa influences the risk of PCa via regulating the age-related trend of T level among males over the life course.

OBJECTIVES

To examine the association between family history of PCa and age-related trend of T levels.

MATERIALS AND METHODS

We used National Health and Nutrition Examination Survey (NHANES) data from 2003 to 2004 (n = 322) to compare the age-specific T levels in males with a family history of PCa and those without.

RESULTS

We found that between two younger age groups (ages 20-39 and 40-59), there was a more pronounced drop-off in T levels among men with a family history of PCa compared to men without a family history.

DISCUSSION AND CONCLUSION

This preliminary analysis suggested that men with a family history of PCa may experience a sharper decline in T level over the life course as compared to males without a family history. However, no conclusions can be made due to small sample sizes. Further longitudinal studies with large sample sizes are needed.