Effects of porcine somatotropin administration on the responses to dietary lysine and a near-ideal blend of amino acids on the amino acid composition of whole-body protein and amino acid accretion rate in growing pigs

An experiment was conducted to assess the effects of porcine somatotropin (pST) on the responses to a near-ideal blend of AA on the AA composition of empty, whole empty body (WEB) protein and WEB essential AA accretion rate in pigs from 22 to 60 kg BW. Forty Hampshire × Yorkshire gilts were individually penned and assigned to a 4 × 2 factorial arrangement of treatments consisting of 4 diets with and without pST injection. A fortified corn-soybean meal basal diet was formulated to contain 1.50% total Lys with Thr, Met, and Trp added to obtain a near-ideal blend of these AA relative to Lys. In 3 additional diets, Lys was reduced to 1.25, 1.00, and 0.75% by diluting the basal diet with cornstarch, cellulose, and sand such that the diets also contained the same ratios of AA. Pigs that received pST were administered a daily i.m. injection of 2 mg of pST. At 60 kg BW, the WEB (carcass, head, viscera, blood, nails, and hair) was ground and analyzed for proximate and AA composition. Administration of pST increased (P < 0.001) accretion rates of WEB protein and essential AA. Increasing dietary essential AA increased (quadratic, P < 0.03) accretion rate of WEB protein, His, Leu, Trp, and Val in pST-treated pigs, but not in untreated pigs. Lysine composition in the accreted WEB protein was not affected (P > 0.05) by dietary Lys. The efficiency of Lys utilization for WEB Lys accretion was linearly affected (P < 0.01) by dietary Lys. These results indicated that the dietary Lys needed to achieve maximum WEB Lys accretion is markedly increased by pST administration.

Improved adherence to hip fracture standards reduces mortality after hip fractures

BACKGROUND

Hip fractures are increasing in incidence due to increasing life expectancy. Mortality continues to improve but it is important to explore which factors are responsible for driving improvements.

METHODS

A cohort of hip fracture patients predating SARS-CoV-2 was examined to determine the predictors of adherence to the six Irish Hip Fracture Standards (IHFS) and the impact of adherence on short (30 day) and long term (1 year) mortality. Our primary aim was assess the impact of a single HFS and cumulative number of HFS on mortality after hip fracture. Our secondary aim was to determine the impact of the HFS which are intrinsically linked to specialist Geriatric care.

RESULTS

Across 962 patients, over 5 years, the factors which were associated with adherence to HFS were female gender, increasing ASA grade and being nursed on an orthopaedic ward. Patients with increasing ASA were more likely to have met HFS 4-6 (Geriatrician review HFS4, bone health HFS5 & specialist falls assessment HFS6), less likely to have surgery within 48 h are more likely to develop a pressure ulcer. If the patient was not nursed on an orthopaedic ward all HFS were less likely to be met. At 30 days HFS 4-6 were associated with a statistically significant odds ratio (OR) of being alive, while at one year HFS 1 (admitted to an orthopaedic ward within 4 h), 5 and 6 were associated with a statistically significant OR of being alive. As increasing numbers of hip fracture standards were met patients were more likely to be alive at 30 days and one year.

CONCLUSION

This study has identified that improved adherence to hip fracture standards are associated with improved mortality at 30 days and one year.

In vivo expansion of gene-targeted hepatocytes through transient inhibition of an essential gene

Homology Directed Repair (HDR)-based genome editing is an approach that could permanently correct a broad range of genetic diseases. However, its utility is limited by inefficient and imprecise DNA repair mechanisms in terminally differentiated tissues. Here, we tested "Repair Drive", a novel method for improving targeted gene insertion in the liver by selectively expanding correctly repaired hepatocytes in vivo. Our system consists of transient conditioning of the liver by knocking down an essential gene, and delivery of an untargetable version of the essential gene in cis with a therapeutic transgene. We show that Repair Drive dramatically increases the percentage of correctly targeted hepatocytes, up to 25%. This resulted in a five-fold increased expression of a therapeutic transgene. Repair Drive was well-tolerated and did not induce toxicity or tumorigenesis in long term follow up. This approach will broaden the range of liver diseases that can be treated with somatic genome editing.

Clinical and Molecular Determinants of PSA Response to Bipolar Androgen Therapy in Prostate Cancer

BACKGROUND

Bipolar Androgen Therapy (BAT) is a novel therapy known to be effective in a subset of men with metastatic castrate resistant prostate cancer (mCRPC). A better understanding of responders and non-responders to BAT would be useful to clinicians considering BAT therapy for patients. Herein we analyze clinical and genetic factors in responders/non-responders to better refine our understanding regarding which patients benefit from this innovative therapy.

METHODS

mCRPC patients were assessed for response or no response to BAT. Patients with PSA declines of greater than 50% from baseline after 2 or more doses of testosterone were considered to be responders. Whereas, Non-responders had no PSA decline after 2 doses of testosterone and subsequently manifest a PSA increase of >50%. Differences between these two groups of patients were analyzed using clinical and laboratory parameters. All patients underwent genomic testing using circulating tumor DNA (ctDNA) and germline testing pre-BAT.

RESULTS

Twenty five patients were non-responders and 16 were responders. Baseline characteristics between non-responders and responders varied. Responders were more likely to have had a radical prostatectomy as definitive therapy and were more likely to have been treated with an androgen receptor (AR) antagonist (enzalutamide or apalutamide) immediately prior to BAT (compared to abiraterone). Duration of prior enzalutamide therapy was longer in responders. Non-responders were more likely to have bone-only metastases and responders were more likely to have nodal metastases. Assays detected ctDNA AR amplifications more often in responding patients. Responders trended toward having the presence of more TP53 mutations at baseline.

CONCLUSIONS

BAT responders are distinct from non-responders in several ways however each of these distinctions are imperfect. Patterns of metastatic disease, prior therapies, duration of prior therapies, and genomics each contribute to an understanding of patients that will or will not respond. Additional studies are needed to refine the parameters that clinicians can utilize prior to choosing among the numerous treatment alternatives available for CRPC patients. This article is protected by copyright. All rights reserved.

Black Patients with Metastatic Castrate-Resistant Prostate Cancer Have a Shorter Time Interval Between PSA and Clinical Progression on Novel Hormonal Therapies plus Avelumab

BACKGROUND

Black men are at higher risk for prostate cancer death. Previous studies showed a benefit of different therapies, including immune-based therapy, for Black men with metastatic prostate cancer. We sought to explore the efficacy of the PD-L1 inhibitor avelumab in Black men with metastatic castrate-resistant prostate cancer (mCRPC) progressing after abiraterone or enzalutamide.

METHODS

This pilot phase II study enrolled self-identified Black patients who developed mCRPC on next-generation hormonal therapies (NHTs) abiraterone acetate or enzalutamide (NCT03770455). Enrolled patients received avelumab 10mg/kg IV every 2 weeks while remaining on the same NHTs. The primary endpoint of our study was ≥ 50% reduction in prostate specific antigen (PSA) at ≥8 weeks.

RESULTS

A total of eight patients were enrolled. The median duration on NHTs prior to enrollment was 364 days (95% CI, 260.9-467.1). The median time to initiate avelumab was 8 days (3-14). With a median follow-up of 196 days, no patients achieved the primary endpoint. The median time to PSA progression was 35 days (95 CI%, 0-94.8) and the median time to radiographic and/or clinical progression was 44 days (95 CI%, 0-118.5). The study was closed prematurely due to safety concerns related to the rapid clinical progression observed in the patients enrolled on study.

CONCLUSION

In conclusion, the addition of avelumab to NHT did not demonstrate clinical activity in Black men with new mCRPC. The unexpected short interval between PSA and radiographic and/or clinical progression observed in this study has potential clinical implications.ClinicalTrials.gov Identifier: NCT03770455 (IND number 139559).

Characterization of ctDNA findings at the end of life in patients with prostate cancer

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Background: Somatic alterations change over time in response to treatment and disease progression in patients with prostate cancer (PCa). We report ctDNA findings of patients who died from PCa within 3 months of a ctDNA assessment to better characterize patients with fatal disease. Methods: A total of 118 patients with PCa specific mortality who had been treated at Tulane Cancer Center and had ctDNA assessments between 2015 and 2022. The ctDNA was assessed by Guardant360 (Guardent Health, Inc) assays to identify alterations, pathogenic mutations and/or copy number alterations (CNAs) in cancer-related genes. Clinical annotation including treatment history, genetics, and staging were also obtained. Statistical analyses included Fischer’s Exact and Wilcoxon tests. Results: Of the 118 patients with PCa specific mortality, 42% (49/118) had a ctDNA assessment <3 months from death. Of 49 CRPC patients tested within 3 months of death, the median number of life extending therapies (LET) at death was 5 (2-9). Patients had a median of 2 (0-6) LET prior to first ctDNA screening and 3 (0-7) LET in between first and last ctDNA assessment. Of the total gene alterations detected on ctDNA analysis, within 3 months of death, the most common alterations detected were 65.3% (32/49) TP53, 44.9% (22/49) AR, 28.6% (14/49) EGFR, 24.5% (12/49) PIK3CA, 22.4% (11/49) MYC, and 20.4% (10/49) CDK6. In a paired analysis(n= 45) of first and last ctDNA screening, AR (OR= 2.35, 95% C.I. (0.99, 5.62), p= 0.05), CDK6 (OR= 4.00, 95% C.I. (1.02, 15.68), p= 0.04), FGFR1 (OR= 9.51, 95% C.I. (1.14, 79.61), p= 0.03), and EGFR (OR= 9.71, 95% C.I. (2.06, 45.83), p= 0.0009) were significantly more likely to be detected in ctDNA screening within 3 months of death. In addition, ctDNA alterations in general were significantly more likely to be detected at the end-of-life (p=< 0.00001). Other ctDNA gene mutations did not have statistically significant increases. Conclusions: An analysis of patients with PCa mortality showed most frequent gene alterations in TP53, AR, EGFR, PIK3CA, MYC, and CDK6. When comparing patients’ first and last ctDNA, alterations were significantly more likely by time of death in AR, CDK6, EGFR, FGFR and there was a significant increase in overall detection of somatic alterations in ctDNA. These analyses are limited to the genes assessed on the ctDNA panel and may or may not reflect all of the functionally relevant alterations. Further the CNAs reported herein may reflect broad genomic changes rather than specific gene alterations.

Comparison of ctDNA between African American and Caucasian patients with CRPC post abiraterone and/or enzalutamide

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Background: Genetic differences between African American and Caucasian patients with advanced prostate cancer may contribute to racial disparities in terms of treatment outcomes and survival, hence further exploration is warranted. We assessed ctDNA differences between African American and Caucasian men in the setting of CRPC post treatment with abiraterone and/or enzalutamide. Methods: From 2015 through 2022 at Tulane Cancer Center, 250 patients with CRPC including 50 African Americans and 200 Caucasian with prior abiraterone and/or enzalutamide treatment were included. All patients had ctDNA assessed via Guardant360. Data including both gene mutations and types of mutations were for between 73-80 genes. Clinical annotation including initial staging, treatment history, and genetic testing were obtained. Statistical analyses included Fisher’s exact test and Wilcoxon rank-sum test. Results: The most common pathogenic/likely pathogenic (P/LP) alterations in both African Americans and Caucasians were TP53 (44% and 46%, respectively), AR (50% and 39%), and PIK3CA (14% and 9%). CDK12 (OR= 8.955, 95% C.I. [2.156, 37.192], p=0.003) and KIT (OR= 5.710, 95% C.I. [1.235, 26.397]. p=0.031) alterations were more frequently detected in African Americans. In terms of pathologic mutation type, frameshift mutations were significantly more frequent in African Americans (OR= 2.293, 95% C.I. [1.103, 4.769], p=0.035). All patients were CRPC at the time of testing and had prior abiraterone and/or enzalutamide, but there were no significant differences between African American and Caucasian patients with regards to prior life-extending therapies. Conclusions: African Americans with CRPC post treatment with abiraterone and/or enzalutamide had a higher frequency of P/LP CDK12 and KIT mutations, which have both been shown to lead to aggressive clinical features and treatment resistance. African Americans also had a higher incidence of frameshift mutations, a finding not previously noted. [Table: see text]

Evaluation of ctDNA in patients with CRPC with pathogenic germline mutations in BRCA2

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Background: Approximately 3-5% of advanced prostate cancer patients have pathogenic BRCA2 mutations in germline tests. In this study, we examine the relationship between pathogenic germline BRCA2 mutation and somatic changes in ctDNA. Methods: Germline screenings were performed by Invitae multi-cancer gene panel which includes 50-84 genes. ctDNA alterations were detected by Guardant 360 assays which report somatic changes in 70-83 genes. All ctDNA samples were collected in post-abiraterone and/or enzalutamide (in CRPC patients). Any pathogenic/likely pathogenic somatic alterations in the ctDNAs with more than 0.1% of allelic fraction were included in this cohort. The type of mutation detected in ctDNA was also assessed (truncating, point, etc.). Statistical significance for comparison is calculated with Fischer Exact Probablity Test and Chi-Square Test. Results: A total of 11 patients had germline BRCA2 pathogenic mutations and ctDNA assays; 267 patients had no germline DNA pathogenic alterations and ctDNA assays. Compared to germline normal patients, the germline BRCA2 mutations were less likely to have AR alterations on ctDNA (OR=0.2133, 95% C.I. [0.087, 0.525], p-value = 0.0003). BRCA2 germline positive patients were also more likely to have a mutated BRCA1, BRCA2, and TP53 ctDNA (OR=7.899, 95% C.I. [1.2745, 48.9548], p=0.055), (OR=7.899, 95% C.I. [1.7529, 16.059], p=0.008), and (OR=6.442, 95% C.I. [2.449, 16.946], p=0.00001), respectively. All other ctDNA assessed genes were mutated at a similar frequency between germline BRCA2 mutated and “normal” germline patients. BRCA2 germline mutations patients are less likely to have copy number alterations (CNVs) (OR=0.3992, 95% C.I. [0.2168, 0.7352], p=0.0031) and more likely to have frameshift mutations (OR=2.3182, 95% C.I. [1.169, 4.5972], p=0.0183). Conclusions: The ctDNA testing in this CRPC population (after abiraterone and/or enzalutamide) was less likely to find AR alterations and more likely to find pathogenic mutations for BRCA1, BRCA2, and TP53 in BRCA2 germline positive patients. In addition, BRCA2 germline positive CRPC patients were more likely to have frameshift mutations and less likely to have CNVs than those with an intact germline. Characterizing the mutational landscape in BRCA2 germline mutated patients may help to better define underlying disease biology. Those with BRCA mutated germline may be less likely to have AR driven tumors. More study is needed to better understand patients with underlying DNA repair defects.

Analysis of TP53 gain of function mutations in metastatic castration-resistant prostate cancer

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Background: TP53, an oncogene implicated in the development of many malignancies, is commonly altered in mCRPC. Gain-of-function mutations in TP53 confer increased oncogenic properties of this gene and play a role in mCRPC. The goal of this study was to characterize somatic TP53 mutations, specifically gain-of-function mutations, in the ctDNA of mCRPC patients in the context of prior therapies. Methods: A retrospective analysis of mCRPC patients at Tulane Cancer Center between 2015-2022 was performed. All patients had ctDNA testing performed with the Guardant360 multigene panel assay. Clinical annotation including initial diagnosis, staging, treatment history, and family history were obtained. TP53 mutations were classified based on existing published functional studies and/or in silico evaluation. Statistical analyses were performed with Fisher's exact and Chi-squared tests where appropriate. Results: 338 mCRPC patients with ctDNA testing were included in this analysis. 76 patients had no prior treatment with either abiraterone or enzalutamide, while 262 patients had been treated with abiraterone and/or enzalutamide. Somatic TP53 mutations were similar in frequency between those with or without abiraterone/enzalutamide pretreatment; 46% (35/76) of patients in the abiraterone/enzalutamide naïve subset had a somatic TP53 mutation, compared to 41% (108/262) of patients previously treated with abiraterone and/or enzalutamide. Only 9% (7/76) of abiraterone/enzalutamide naïve patients had a TP53 gain-of-function mutation, compared to 19% (49/262) of patients previously treated with one or both drugs ( p = 0.05). The most common type of TP53 mutation was loss-of-function. There were no significant associations between TP 53 mutations and occurrence of other common mutations. Conclusions: mCRPC patients with prior treatment of abiraterone and/or enzalutamide were significantly more likely to have a gain-of-function TP53 mutation. Further studies are needed to investigate therapeutic implications of these findings.

Genomic alterations in patients with prostate cancer with liver metastases

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Background: mCRPC patients with liver metastases have a poor prognosis and often progress rapidly on a variety of treatments. Previously, preliminary ctDNA analyses of mCRPC patients with liver metastases showed a range of commonly altered genes in patients with liver metastases (Ranasinghe et al; 2019). In this follow-up, we evaluated ctDNA alterations in an expanded cohort of mCRPC patients with liver metastases. Methods: From Tulane Cancer Center, retrospective review of mCRPC patients was used to identify patients with confirmed liver metastasis. All liver metastases were confirmed based on imaging data. All patients included had ctDNA evaluated with a multi-gene cancer panel via Guardant 360 assay (Guardant Health, Inc). Additional clinical annotation including family history, germline testing, staging, imaging, and laboratory values. Statistical analyses were performed with Fisher’s Exact and Wilcoxon Rank Sum tests. Results: 158 mCRPC patients with appropriate diagnostic imaging as well as ctDNA testing. From this group, 8% (n= 12) had confirmed liver metastases. Among the patients with liver metastasis, the most common alterations detected were in AR (50%; 6/12) and PIK3CA (25%; 3/12). Patients with liver metastasis were more likely to have amplifications in FGFR1 detected in their ctDNA (OR= 14.40; 95% C.I. (1.83, 113.22); p= 0.03). In addition to ctDNA, germline data was assessed, and it was found that patients with liver metastasis were more likely to have a pathogenic germline mutation (OR= 7.61; 95% C.I. (2.85, 20.31); p<.0001). The most common germline mutations detected in patients with liver metastasis were in BRCA2 (n= 3) and TP53 (n= 2). Conclusions: Though liver metastasis are less common in prostate cancer, it often occurs following extensive treatment and results in a poor prognosis for patients. In patients with liver metastasis, FGFR1 amplification was more often detected in ctDNA. Importantly, patients with liver metastasis were significantly more likely to have a pathogenic germline alteration.

Evaluation of ctDNA in patients treated with lutetium-177-PSMA-617

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Background: Lutetium-177- PSMA-617 (Lu-177) is a radioligand therapy that delivers radiation to PSMA-expressing cells in patients with advanced prostate cancer. In this study, we aimed to analyze ctDNA in responders and non-responders after Lu-177 treatments. Methods: Data was retrospectively collected on 31 heavily pre-treated metastatic CRPC patients who received Lu-177 treatment at Tulane Cancer Center. All patients fulfilled VISION criteria for treatment and all had ctDNA assessment with Guardant 360 within 30 days prior to first treatment with Lu-177. Of the 31 patients, 7 had paired ctDNA assessment both prior initiation of treatment and at the end of treatment. Clinical data such as PSA response (PSA decline 50% or more) to Lu-177, initial diagnosis, pathology, treatment history, and relevant germline genetic data were collected. Results: Of the 31 patients who received Lu-177 treatment, 18 had PSA response to Lu-177 (responders) and 13 did not (non-responders). In ctDNA mutational analyses, there were no significant differences detected prior to treatment between responders and non-responders. There was, however, a significant increase in the presence of copy number amplifications in non-responders (n= 11/13) when compared to responders (n= 7/18) (OR= 8.64, 95% C.I. [1.46, 51.25)], p = 0.0250). Amplification was detected in 10 genes in non-responders, whereas responders only had amplifications in AR (7/18) and EGFR (1/18). The most frequently amplified genes in non-responders were AR (8/13), CCNE1 (6/13), EGFR (4/13), and FGFR1 (4/13). Furthermore, in analysis of the 7 patients with paired ctDNA assessments, amplifications increased during treatment with Lu-177. Conclusions: Radioligand therapy with Lu-177 has been shown to prolong life and reduce disease progression. Our analysis of the cohort of Lu-177 treated patients showed that the presence of gene amplifications in ctDNA may play a role in predicting resistance to treatment with Lu-177.

Temperature-controlled Laminar Airflow (TLA) in symptomatic severe asthma – a post hoc analysis of severe exacerbations, quality of life and health economics

Purpose

Uncontrolled severe asthma constitutes a major economic burden to society. Add-ons to standard inhaled treatments include inexpensive oral corticosteroids and expensive biologics. Nocturnal treatment with Temperature-controlled Laminar Airflow (TLA; Airsonett®) could be an effective, safe and cheaper alternative. The potential of TLA in reducing severe asthma exacerbations was addressed in a recent randomised placebo-controlled trial (RCT) in patients with severe asthma (Global Initiative for Asthma (GINA) step 4/5), but the results were inconclusive. We re-analysed the RCT with severe exacerbations stratified by the level of baseline asthma symptoms and Quality of Life.

Methods

More uncontrolled patients, defined by Asthma Control Questionnaire 7 (ACQ7) > 3, EuroQoL 5-Dimension Questionnaire Visual Analogue Scale (EQ5D-VAS) ≤ 65 and Asthma Quality of Life Questionnaire (AQLQ) ≤ 4 were selected for re-analysis. The rates of severe asthma exacerbations, changes in QoL and health-economics were analysed and compared between TLA and placebo.

Results

The study population included 226 patients (113 TLA / 113 placebo.) The rates of severe asthma exacerbations were reduced by 33, 31 and 25% (p = 0.083, 0.073, 0.180) for TLA compared to placebo, dependent on selected control measures (ACQ7, EQ5D-VAS, AQLQ, respectively). For patients with less control defined by AQLQ≤4, the difference in mean AQLQ0-12M between TLA and placebo was 0.31, 0.33, 0.26 (p = 0.085, 0.034, 0.150), dependent on selected covariate (AQLQ, EQ5D-VAS, ACQ7, respectively). For patients with poor control defined by ACQ7 > 3, the difference in EQ5D-5 L utility scores between TLA and placebo was significant at 9 and 12 months with a cost-effective ICER. The results from the original study did not demonstrate these differences.

Conclusion

This post hoc analysis demonstrated an effect of TLA over placebo on severe exacerbations, asthma control and health economics in a subgroup of patients with more symptomatic severe allergic asthma. The results are consistent with the present recommendations for TLA. However, these differences were not demonstrated in the full study. Several explanations for the different outcomes have been outlined, which should be addressed in future studies.

Funding

NIHR Health Technology Assessment Programme and Portsmouth Hospitals NHS Trust.

147 ESTABLISHING A PERI-OPERATIVE MEDICAL SERVICE (POMS) FOR OLDER PEOPLE IN UROLOGY

Background

Older adults account for approximately 65% of patients undergoing urological procedures therefore as the population ages the demand is anticipated to rise. The benefits of Comprehensive Geriatric Assessment (CGA) have been proven in ortho-geriatrics and a number of surgical specialties but evidence in urology is lacking. The aim of this study was to assess the impact of a Peri-Operative Medical Service for older people (POMS) on patient outcomes in a urology inpatient population.

Methods

This was a single-centre retrospective study of patients ≥50 years with length of stay (LOS) &gt;1 day admitted over two four month periods in 2018 (Pre-intervention) and 2019 (Intervention). Group differences in LOS and complications were examined using univariate regressions and then adjusted for sex, emergency admission, severity of procedure and Charlson Co-morbidity Index which also accounts for age. Secondary outcomes were to record undiagnosed medical conditions identified and the interventions made by the POMS.

Results

There were a total of 218 admissions from 211 patients with equal numbers of admissions in both the pre-intervention and intervention groups. No significant differences were detected for LOS (median 3 vs 4 days, p=0.11) or complications (32(29%) vs 40(37%), p=0.23) between pre-intervention and intervention groups. A new medical diagnosis was made in 13 (12%) of the pre-intervention v 43(39%) of the intervention group (p&lt;0.001). The POMS recommended a change to management in 102 admissions (94%). The most common intervention was medication review: 64(59%) v 19(17%) (p&lt;0.001).

Conclusion

The Peri-Operative Medical Service for older people can improve patient management by identifying and managing medical issues, complications and geriatric syndromes that may otherwise have been missed.

A sampling, exposure and receptor framework for identifying factors that modulate behavioural responses to disturbance in cetaceans

The assessment of behavioural disturbance in cetacean species (e.g. resulting from exposure to anthropogenic sources such as military sonar, seismic surveys, or pile driving) is important for effective conservation and management. Disturbance effects can be informed by Behavioural Response Studies (BRSs), involving either controlled exposure experiments (CEEs) where noise exposure conditions are presented deliberately to meet experimental objectives or in opportunistic contexts where ongoing activities are monitored in a strategic manner. In either context, animal-borne sensors or in situ observations can provide information on individual exposure and disturbance responses. The past 15 years of research have greatly expanded our understanding of behavioural responses to noise, including hundreds of experiments in nearly a dozen cetacean species. Many papers note limited sample sizes, required knowledge of baseline behaviour prior to exposure and the importance of contextual factors modulating behavioural responses, all of which in combination can lead to sampling biases, even for well-designed research programs. It is critical to understand these biases to robustly identify responses. This ensures outcomes of BRSs help inform predictions of how anthropogenic disturbance impacts individuals and populations. Our approach leverages concepts from the animal behaviour literature focused on helping to avoid sampling bias by considering what shapes an animal's response. These factors include social, experience, genetic and natural changes in responsiveness. We developed and applied a modified version of this framework to synthesise current knowledge on cetacean response in the context of effects observed across marine and terrestrial taxa. This new 'Sampling, Exposure, Receptor' framework (SERF) identifies 43 modulating factors, highlights potential biases, and assesses how these vary across selected focal species. In contrast to studies that identified variation in 'Exposure' factors as a key concern, our analysis indicated that factors relating to 'Sampling' (e.g. deploying tags on less evasive individuals, which biases selection of subjects), and 'Receptor' (e.g. health status or coping style) have the greatest potential for weakening the desired broad representativeness of BRSs. Our assessment also highlights how potential biases could be addressed with existing datasets or future developments.

Evaluation of plasma nucleosome concentrations in dogs with a variety of common cancers and in healthy dogs

Background

Cell free DNA, in the form of nucleosomes, is released into circulation during apoptosis and necrosis in a variety of diseases. They are small fragments of chromosomes that are composed of DNA wrapped around a histone core made of four duplicate histone proteins forming an octamer. The nucleosome compartment is a relatively uninvestigated area of circulating tumor biomarkers in dogs. The objectives of this study were to quantify and better characterize nucleosome concentrations in 528 dogs with various common malignancies and compare them to 134 healthy dogs.

Results

The sensitivity of increased circulating nucleosome concentrations for the detection of cancer in all dogs was 49.8% with a specificity of 97% with an area under the curve of 68.74%. The top 4 malignancies detected by the test included lymphoma, hemangiosarcoma, histiocytic sarcoma and malignant melanoma. The malignancies least likely to be detected were soft tissue sarcomas, osteosarcoma and mast cell tumors.

Conclusions

A variety of tumor types may cause increased nucleosome concentrations in dogs. Tumors of hematopoietic origin are most likely to cause elevations and local tumors such as soft tissue sarcomas are least likely to cause elevations in plasma nucleosome concentrations.

Relation of Myocardial Perfusion Reserve and Left Ventricular Ejection Fraction in Ischemic and Nonischemic Cardiomyopathy

Quantification of myocardial perfusion reserve (MPR) using vasodilator stress cardiac magnetic resonance is increasingly used to detect coronary artery disease. However, MPR can also be altered because of changes in microvascular function. We aimed to determine whether MPR can distinguish between ischemic cardiomyopathy (IC) secondary to coronary artery disease and non-IC (NIC) with microvascular dysfunction and no underlying epicardial coronary disease. A total of 60 patients (mean age 65 ± 14 years, 30% women), including 31 with IC and 29 with NIC, were identified from a pre-existing vasodilator stress cardiac magnetic resonance registry. Short-axis cine slices were used to measure left ventricular ejection fraction (LVEF) using the Simpson method of disks. MPR index (MPRi) was determined from first-pass myocardial perfusion images during stress and rest using the upslope ratio, normalized for the arterial input and corrected for rate pressure product. Patients in both groups were divided into subgroups of LVEF ≤35% and LVEF >35%. Differences in MPRi between the subgroups were examined. MPRi was moderately correlated with LVEF in patients with NIC (r = 0.53, p = 0.03), whereas the correlation in patients with IC was lower (r = 0.32, p = 0.22). Average LVEF in NIC and IC was 34% ± 8% and 35% ± 8%, respectively (p = 0.63). MPRi was not significantly different in IC compared with NIC (1.17 [0.88 to 1.61] vs 1.23 [1.07 to 1.66], p = 0.41), including the subgroups of LVEF (IC: 1.20 ± 0.56 vs NIC: 1.15 ± 0.24, p = 0.75 for LVEF ≤35% and IC: 1.35 ± 0.44 vs NIC: 1.58 ± 0.50, p = 0.19 for LVEF >35%). However, MPRi was significantly lower in patients with LVEF ≤35% compared with those with LVEF>35% (1.17 ± 0.40 vs 1.47 ± 0.47, p = 0.01). Similar difference between LVEF groups was noted in the patients with NIC (1.15 ± 0.24 vs 1.58 ± 0.50, p = 0.006) but not in the patients with IC (1.20 ± 0.56 vs 1.35 ± 0.44, p = 0.42). MPRi can be abnormal in the presence of left ventricular dysfunction with nonischemic etiology. This is a potential pitfall to consider when using this approach to detect ischemia because of epicardial coronary disease using myocardial perfusion imaging.

Liquid biopsy AR/enhancer alteration detection before AR-targeted therapy and correlation with survival in metastatic castrate-resistant prostate cancer patients

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Background: Patients with metastatic castrate-resistant prostate cancer (mCRPC) have a variety of different systemic therapy options, yet survival outcomes remain poor. To minimize the chance of rapid resistance, it is critical to be able to personalize therapy upfront. We previously developed a cell-free DNA liquid biopsy assay that tracks alterations in the androgen receptor ( AR) locus, including its upstream enhancer (EnhanceAR-Seq). This assay demonstrated the ability to stratify patients based on resistance to AR-directed agents after treatment started (Dang and Chauhan et al., JCO PO, 2020). Here we evaluated if the same approach can accurately risk-stratify patients with mCRPC prior to the initiation of first-line AR-targeted therapy. Methods: We performed EnhanceAR-Seq on plasma cell-free DNA samples from 55 mCRPC patients prior to the initiation of AR-targeted therapy. Forty-seven patients were treated with Abiraterone and eight with Enzalutamide. Five patients were excluded due to having already received AR-targeted therapy or being lost to follow-up. Kaplan-Meier analysis was performed, and progression-free survival (PFS) and overall survival (OS) were assessed in relation to AR/enhancer locus status (wild-type vs. altered). Results: Median follow-up time was 30 months. EnhanceAR-Seq noninvasively detected AR/enhancer locus alterations in 36% (18/50) of the patients in our cohort, while 64% (32/50) were determined to be wild-type. Alterations detected by the assay were AR amplification (12/18), AR nonsynonymous single nucleotide variants (4/18), AR truncation (2/18), and AR enhancer amplification (13/18). Eleven patients had both AR gene body and enhancer amplifications present. Strikingly, patients with AR/enhancer alterations detected in plasma cell-free DNA were found to have significantly worse outcomes, with median PFS of 16.3 (wild-type) vs. 10.8 months (altered) (p = 0.046; HR = 2.10), and OS trending toward significantly different with median 34.3 (wild type) vs. 24.7 months (altered) (p = 0.19; HR = 1.05). Conclusions: AR/enhancer locus alterations in patients with mCRPC, as detected noninvasively by EnhanceAR-Seq, corresponded with significantly worse PFS and trended toward significantly worse OS. Our results support the role of cell-free DNA AR/enhancer locus alterations as prognostic, and potentially predictive, biomarkers that enable more precise upfront risk stratification and treatment personalization.

Comparative ctDNA analyses of African-American and Caucasian patients with CRPC

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Background: Somatic genetic analyses have indicated genetic distinctions in AA as compared to C patients. In the Mahal et al. study (1) evaluating a broad spectrum of pts with tissue based assays, FOXA1 mutations were more frequent in AA men and TP53 mutations were less frequent in AA men as compared to C men. In a separate analysis by Khashab et al. (2) conducted in prostate cancer pts receiving androgen deprivation therapy, using both tissue and ctDNA assays, the authors reported AR, TP53, SPOP, and BRCA2 were more frequently mutated in AA men as compared to C men. Herein we assessed the Guardant 360 platform in assessing ctDNA differences in AA and C men, all of whom had CRPC at the time assays were performed. Methods: Guardant 360 was used to analyze ctDNA with a cut-off of >0.5% for allelic fractions for ascertaining the presence or absence of pathogenic mutations and various amplifications. Lower allelic fractions were not analyzed given these may represent less relevant mutations. Depending on the timing of the assays (2015-2021), 70-83 genes were analyzed. All pts had CRPC and all patients were treated at Tulane Cancer Center. Chi Square analyses were used to determine statistical differences. AR, BRCA2, and TP53 were assessed but SPOP and FOXA1 were not assessable in the Guardant ctDNA assay. Both mutations and amplifications were evaluated. Results: Among men with CRPC, a total of 48 AA men and 179 C men were analyzed using ctDNA. Clear distinctions were found in the alteration reported in APC, TP53, and CDK12. TP53 was less frequently mutated and other genes were more frequently altered in the AA men. Conclusions: Using Guardant ctDNA assays in men with CRPC, clear distinctions were found in AA men as compared to C men. It is unclear why these results differ from that reported by others, however distinctions in both the assays and the populations are notable.[Table: see text]

Evaluation of ctDNA alterations in mCRPC patients with germline pathogenic mutations

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Background: Germline alterations are found in approximately 12-17% of CRPC patients. Similarly, evaluating tumoral changes with circulating tumor DNA (ctDNA) has become an increasingly useful tool for understanding mechanisms underpinning disease progression. In this study, we evaluated both germline and somatic genetic changes in patients with mCRPC. Methods: Patients included had germline screening and ctDNA analyzed with the Guardant 360 assay. All patients were CRPC at the time of Guardant testing. Germline alterations were classified as pathogenic/likely-pathogenic or not pathogenic. Only ctDNA alterations with an alleleic fraction greater than 0.5% were included in analyses. Additional evaluation of CRPC status, treatment history, family history and other clinical covariates are ongoing. Chi-square and Fischer’s Exact tests were used for comparison of cohorts. Results: A total of 168 Caucasian CRPC patients had Guardant 360 testing at time of progression and germline testing between 2015-2021. 61% (n = 102/168) of patients have previously had treatment with abiraterone, 49% (n = 82/168) have had Enzalutamide and 40% (n = 68/168) have had treatment with taxanes. 12% (n = 20/168) of CRPC patients had a pathogenic/likely-pathogenic (P/LPv) germline alteration, 46% (n = 77/168) had a germline variant of unknown significance (VUS), 42% (n = 71/168) were germline negative. CRPC patients with pathogenic germline mutations were significantly more likely to have subsequent somatic alterations in BRCA2 (OR = 5.05, 95% C.I. (1.11, 23.01), p = 0.055), NF1 (OR = 7.89, 95% C.I. (2.15, 28.10), p = 0.004), and TP53 (OR = 3.52, 95% C.I. (1.28, 9.68), p = 0.015). In TP53, among germline positive patients, 45% (n = 9/20) had TP53 alterations compared to 30% (n = 45/148) of germline negative patients. Conclusions: Germline positive (P/LPv) CRPC patients were significantly more likely to have somatic alterations in BRCA2, NF1, and TP53. Understanding the totality of genetic changes, both germline and acquired somatic alterations is essential as the arsenal of targeted treatment for CRPC continues to expand. Additional studies including longitudinal assessment genetic changes and clinical correlates will be necessary to evaluate these findings in the context of treatment outcomes and disease progression.

Circulating tumor DNA responses to high-dose testosterone injections in CRPC patients

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Background: Some proportion of men with CRPC have favorable responses to high doses of testosterone (HDT) and some do not. Genomic determinants of these responders and non-responders are poorly understood. Herein ctDNA predictors of response are assessed using a responder/non-responder analysis. Methods: All men with CRPC had been pretreated with abiraterone, enzalutamide, or both. A ctDNA test was obtained prior to high doses of testosterone (administered as a dose of 400 mg IM testosterone cypionate every 3-4 weeks). Guardant 360 was used to analyze ctDNA (with an allelic fraction cut-off of > 0.5%) to ascertain the presence or absence of pathogenic mutations. Lower allelic fractions were not analyzed. Responders had a PSA decline of 50% or more (N = 16), non-responders received at least two doses of testosterone but never had any PSA decline at all (N = 20). All patients were treated at Tulane Cancer Center. Results: AR amplifications were more commonly detected (p = 0.036) pre-treatment in the ctDNA of responders (5/16) as compared to non-responders (1/20). No differences were found in those with common AR mutations; T878A was detected in 2/16 responders and 2/20 non-responders, L702H was detected in 1/16 responders and 2/20 non-responders. No differences were seen with regard to TP53 mutations, 6/20 non-responders and 7/16 responders. Non- AR/non- TP53 mutations were not distinct in the two groups but trended (P = 0.15) toward being more common in non-responders (5/16 in responders versus 11/20 non-responders). Pre- and post- ctDNA analyses were conducted in 5/6 patients for those with AR amplification at baseline. In all 5 of these patients, the degree of AR amplification diminished after testosterone injections. Conclusions: In this analysis of CRPC patients who were responders and non-responders to 400 mg testosterone cypionate q 3-4 weeks (post-abiraterone and/or enzalutamide), only AR amplifications in ctDNA were predictive of response. In all measured patients, the degree of AR amplification in the ctDNA diminished after testosterone injections.

Comparison of germline mutations in African American and Caucasian men with metastatic prostate cancer

BACKGROUND

The goal of this study is to evaluate germline genetic variants in African American men with metastatic prostate cancer as compared to those in Caucasian men with metastatic prostate cancer in an effort to understand the role of genetic factors in these populations.

METHODS

African American and Caucasian men with metastatic prostate cancer who had germline testing using multigene panels were used to generate comparisons. Germline genetic results, clinical parameters, and family histories between the two populations were analyzed.

RESULTS

A total of 867 patients were included in this retrospective study, including 188 African American and 669 Caucasian patients. There was no significant difference in the likelihood of a pathogenic or likely-pathogenic variants (PV/LPVs) between African American and Caucasian patients (p = .09). African American patients were more likely to have a variant of unknown significance than Caucasians (odds ratio [OR] = 1.95; p < .0001). BRCA1 PV/LPVs were higher in African Americans (OR = 4.86; p = .04). African American patients were less likely to have a PV/LPV in non-BRCA DNA repair genes (OR = 0.30; p = .008). Family history of breast (OR = 2.09; p = .002) or ovarian cancer (OR = 2.33; p = .04) predicted PV/LPVs in Caucasians but not African-Americans. This underscores the limitations of family history in AA men and the importance of personal history to guide germline testing in AA men.

CONCLUSIONS

In metastatic prostate cancer patients, PV/LPVs of tested genes did not vary by race, BRCA1 PV/LPVs were more common in the African American subset. However, PV/LPVs in non-BRCA DNA repair genes were less likely to be encountered in African Americans. Family history associated with genetic testing results in Caucasians only.

Feasibility, Acceptability, and Outcomes of a Yoga-Based Meditation Intervention for Hospice Professionals to Combat Burnout

(1) Background. This research examined the feasibility, acceptability and outcomes of delivering a 6-week yoga-based meditation intervention to clinical teams of hospice professionals (HPs) at a large non-profit hospice organization. The intervention was designed to increase mind-body integration and combat burnout. This article was written for different audiences, including research scientists who study interoception, burnout, meditation, or yoga, designers of meditation interventions, and hospice organizations looking for ways to mitigate HP burnout. (2) Methods. The intervention was launched within clinical teams, beginning with a half-hour online introduction to the program and exposure to the week 1 meditation at each team's monthly all-staff meeting. Throughout the program, HPs could access the meditations on their own via their workplace computers, tablets, and smartphones. Online pre- and post-intervention surveys were submitted by 151 HPs, 76 of whom were exposed to the intervention and completed both surveys. The surveys assessed burnout using the Professional Fulfillment Index and mind-body integration using the Multidimensional Assessment of Interoceptive Awareness scales. (3) Results. Two-thirds of HPs who were present at a staff meeting where the program was introduced went on to do a meditation on their own at least once. Half of HPs expressed a desire to continue with access to the meditations after the 6-week program ended. Due to COVID-19 work from home restrictions, three-fourth of HPs did a meditation at home, 29% in a car between patient visits (not while driving), and 23% at the office. Higher interoceptive awareness was significantly related to lower burnout, particularly lower work exhaustion. Meditation frequency was significantly related to higher interoceptive awareness but not to burnout. Interpersonal disengagement was rare and temporary. (4) Conclusions. Findings showed that the yoga-based meditation intervention was feasible and acceptable and associated with higher interoceptive awareness. The results point to a role for interoceptive awareness in reducing the risk for burnout.

Lyme Carditis Presenting to a Community Hospital in a Non-Endemic Region

Lyme borreliosis is an infectious disease that is increasing in frequency and can cause various forms of carditis in its disseminated phase. In otherwise healthy patients presenting with new-onset atrio-ventricular dissociation, Lyme carditis must be on the differential; however, due to its rarity in non-endemic regions, the clinician must remain vigilant and keep it on the differential. The objective of this clinical case report is to call attention to the importance of rapid diagnosis of Lyme carditis in regions where the disease is not common. The patient presented in this report is a 27-year-old, previously healthy male complaining of fatigue and presyncope over the past 48 hours who presented to a community ED in western Washington State. He had been traveling the country rock climbing and recalled a febrile illness and rash in the preceding three months. He was found to be in third-degree atrio-ventricular block on admission to the ED and was promptly diagnosed with Lyme carditis. He was hospitalized on telemetry monitoring and was treated with transvenous cardiac pacing and IV ceftriaxone. His atrio-ventricular block gradually resolved and he was discharged without need for permanent pacemaker placement. He was able to return to his active lifestyle of hiking, climbing, and other outdoor recreational activities. This case demonstrates how Lyme carditis must be a foremost consideration in a patient with new-onset conductive heart disease, particularly in patients without risk factors for other causes of atrio-ventricular block. A thorough travel and exposure history must be taken when Lyme carditis is suspected in patients presenting outside of areas where the disease is endemic.

Effect of Low-dose and Standard-dose Aspirin on PGE2 Biosynthesis Among Individuals with Colorectal Adenomas: A Randomized Clinical Trial

Low-dose aspirin is recommended by the U.S. Preventive Services Task Force for primary prevention of colorectal cancer in certain individuals. However, broader implementation will require improved precision prevention approaches to identify those most likely to benefit. The major urinary metabolite of PGE2, 11α-hydroxy-9,15-dioxo-2,3,4,5-tetranor-prostane-1,20-dioic acid (PGE-M), is a biomarker for colorectal cancer risk, but it is unknown whether PGE-M is modifiable by aspirin in individuals at risk for colorectal cancer. Adults (N = 180) who recently underwent adenoma resection and did not regularly use aspirin or NSAIDs were recruited to a double-blind, placebo-controlled, randomized trial of aspirin at 81 or 325 mg/day for 8-12 weeks. The primary outcome was postintervention change in urinary PGE-M as measured by LC/MS. A total of 169 participants provided paired urine samples for analysis. Baseline PGE-M excretion was 15.9 ± 14.6 (mean ± S.D, ng/mg creatinine). Aspirin significantly reduced PGE-M excretion (-4.7 ± 14.8) compared with no decrease (0.8 ± 11.8) in the placebo group (P = 0.015; mean duration of treatment = 68.9 days). Aspirin significantly reduced PGE-M levels in participants receiving either 81 (-15%; P = 0.018) or 325 mg/day (-28%; P < 0.0001) compared with placebo. In 40% and 50% of the individuals randomized to 81 or 325 mg/day aspirin, respectively, PGE-M reduction reached a threshold expected to prevent recurrence in 10% of individuals. These results support that aspirin significantly reduces elevated levels of PGE-M in those at increased colorectal cancer risk to levels consistent with lower risk for recurrent neoplasia and underscore the potential utility of PGE-M as a precision chemoprevention biomarker. The ASPIRED trial is registered as NCT02394769.

Hospice Employees' Perceptions of Their Work Environment: A Focus Group Perspective

Burnout in healthcare professionals can lead to adverse effects on physical and mental health, lower quality of care, and workforce shortages as employees leave the profession. Hospice professionals are thought to be at particularly high risk for burnout. The purpose of the study was to evaluate workplace perceptions of interdisciplinary hospice care workers who provide care to patients at end of life. Six focus groups and one semi-structured interview were conducted with mixed group of social workers, managers, nurses, hospice aides, chaplains, support staff, and a physician (n = 19). Findings from the groups depicted both rewards and challenges of hospice caregiving. Benefits included intrinsic satisfaction from the work, receiving positive patient and family feedback, and teamwork. Challenges reflected issues with workload, technology issues, administrative demands, travel-related problems, communication and interruptions, difficulties with taking time off from work and maintaining work-life integration, and coping with witnessing grief/loss. Hospice workers glean satisfaction from making meaningful differences in the lives of patients with terminal illness and their family members. It is an expected part of the job that certain patients and situations are particularly distressing; team support and targeted grief support is available for those times. Participants indicated that workload and administrative demands rather than dealing with death and dying were the biggest contributors to burnout. Participants reported episodic symptoms of burnout followed by deliberate steps to alleviate these symptoms. Notably, for all except one of the participants, burnout was cyclical. Symptoms would begin, they would take steps to deal with it (e.g., taking a mental health day), and they recovered. At an organizational level, a multipronged approach that includes both personal and occupational strategies is needed to support professional caregivers and help mitigate the stressors associated with hospice work.

Improving estimates of diving lung volume in air-breathing marine vertebrates

The air volume in the respiratory system of marine tetrapods provides a store of O₂ to fuel aerobic metabolism during dives; however, it can also be a liability, as the associated N₂ can increase the risk of decompression sickness. In order to more fully understand the physiological limitations of different air-breathing marine vertebrates, it is therefore important to be able to accurately estimate the air volume in the respiratory system during diving. One method that has been used to do so is to calculate the air volume from glide phases - periods of movement during which no thrust is produced by the animal - which many species conduct during ascent periods, when gases are expanding owing to decreasing hydrostatic pressure. This method assumes that there is conservation of mass in the respiratory system, with volume changes only driven by pressure. In this Commentary, we use previously published data to argue that both the respiratory quotient and differences in tissue and blood gas solubility potentially alter the mass balance in the respiratory system throughout a dive. Therefore, near the end of a dive, the measured volume of gas at a given pressure may be 12-50% less than from the start of the dive; the actual difference will depend on the length of the dive, the cardiac output, the pulmonary shunt and the metabolic rate. Novel methods and improved understanding of diving physiology will be required to verify the size of the effects described here and to more accurately estimate the volume of gas inhaled at the start of a dive.

OP0297 EFFICACY AND SAFETY OF ROMOSOZUMAB AMONG POSTMENOPAUSAL WOMEN WITH OSTEOPOROSIS AND MILD-TO-MODERATE CHRONIC KIDNEY DISEASE

Background:

Osteoporosis and renal insufficiency are coexisting disease states in a substantial proportion of postmenopausal women. Since bisphosphonates are generally contraindicated in patients with estimated glomerular filtration rate (eGFR) <35 mL/min, it is important to evaluate other osteoporosis treatments in this setting.

Objectives:

To determine if baseline renal function affects the efficacy and safety of romosozumab.

Methods:

We performed post hoc analyses of two clinical trials of romosozumab in postmenopausal women with osteoporosis. In ARCH (NCT01631214), 4,093 patients were randomised 1:1 to romosozumab 210 mg monthly or alendronate 70 mg weekly for 12 months (mean age: 74.3 years; 96.1% with prevalent vertebral fractures [VFx]). In FRAME (NCT01575834), 7,180 patients were randomised 1:1 to romosozumab 210 mg or placebo monthly for 12 months (mean age: 70.9 years; 18.3% with prevalent VFx). For these analyses, patients were categorised by baseline eGFR (mL/min/1.73m2): normal renal function (eGFR ≥90), mild renal insufficiency (eGFR 60–89), or moderate renal insufficiency (eGFR 30–59). Least squares mean (LSM) percent change from baseline in bone mineral density (BMD) at the lumbar spine, total hip, and femoral neck; incidence of new VFx and adverse events (AEs); and changes in renal function were assessed for each eGFR category at Month 12 of the double-blind treatment period.

Results:

At baseline, most patients had mild/moderate renal insufficiency: 84% in ARCH, 88% in FRAME. In both studies, change from baseline in BMD was significantly higher in the romosozumab group across baseline eGFR categories (Figure). There was an interaction between BMD increase and renal function, and although BMD increase was not as large in women with impaired renal function, differences between romosozumab and control groups remained significant (Figure). In ARCH, among patients with eGFR ≥90, 60–89, and 30–59, the incidence of new VFx (romosozumab vs alendronate) at Month 12 was 3.3% vs 7.3%, 3.2% vs 3.9%, and 3.4% vs 6.2% in ARCH. In FRAME, the incidence of new VFx (romosozumab vs placebo) at Month 12 was 0.5% vs 3.0%, 0.4% vs 1.5%, and 0.6% vs 2.1%.

In both studies, the incidences of AEs and serious AEs were similar in both treatment groups within and across eGFR categories. AEs of mild-to-moderate hypocalcaemia (investigator reported) occurred in two patients in ARCH (one romosozumab [eGFR 60–89] and one alendronate [eGFR ≥90]), and one patient in FRAME (romosozumab [eGFR 60–89]). Five patients in ARCH (all in the alendronate group) and 19 patients in FRAME (14 romosozumab, 5 placebo) had decreases in serum Ca levels (albumin adjusted); in the romosozumab group all were mild (<LLN–8.0 mg/dL) or moderate (<8.0–7.0 mg/dL). A similar percentage of patients in each group had changes in renal function over 12 months of treatment.

Conclusion:

The efficacy and safety of romosozumab vs alendronate or placebo was similar among postmenopausal women with osteoporosis and different levels of renal function.

Acknowledgments:

This study was funded by Amgen, Astellas and UCB Pharma. Editorial services were provided by Costello Medical.

Disclosure of Interests:

Paul Miller Grant/research support from: Amgen, Radius Health, Ultragenyx, Consultant of: Amgen, Radius Health, Jonathan Adachi Consultant of: Amgen, Speakers bureau: Amgen, Ben-Hur Albergaria Consultant of: Amgen Inc., Eli Lilly, Speakers bureau: Amgen Inc., Eli Lilly, Angela M Cheung Consultant of: Amgen, Eli Lilly, Arkadi Chines Shareholder of: Amgen Inc., Employee of: Amgen Inc., Evelien Gielen Consultant of: Amgen Inc., Takeda, Sandoz and UCB Pharma, Speakers bureau: Amgen Inc., Takeda, Sandoz and UCB Pharma, Bente Langdahl Grant/research support from: Amgen, NovoNordisk, Consultant of: Amgen Inc., Eli Lilly, UCB Pharma, Akimitsu Miyauchi Consultant of: Amgen Inc., Astellas BioPharma K.K., Teijin Pharma, Mary Oates Shareholder of: Amgen Inc., Employee of: Amgen Inc., Ian Reid Consultant of: Amgen Inc., Eli Lilly, Speakers bureau: Amgen Inc., Eli Lilly, Norma Ruiz Santiago Shareholder of: Amgen Inc., Employee of: Amgen Inc., Mark Vanderkelen Employee of: UCB Pharma, Wenjing Yang Shareholder of: Amgen Inc., Employee of: Amgen Inc., Zhigang Yu Shareholder of: Amgen Inc., Employee of: Amgen Inc.

Sapphire advanced mitigation process: wet etch to expose sub-surface damage and increase laser damage resistance and mechanical strength

A novel, to the best of our knowledge, method of wet chemical etching of sapphire workpieces (such as optics, wafers, windows, and cones), called the sapphire advanced mitigation process (or sapphire AMP), has been developed that exposes sub-surface mechanical damage created during the optical fabrication process and significantly enhances the surface laser damage resistance ($ \gt {2{\times}}$>2×) and mechanical strength (up to $\sim{2.6{\times}}$∼2.6×). Sapphire AMP involves first treating the workpiece with a mixture of sulfuric and phosphoric acid $([{\rm H_{2}{\rm SO_{4}}}]:[{\rm H_{3}{\rm PO_{4}}}]=1:3)$([H₂SO₄]:[H₃PO₄]=1:3) at 220°C, followed with phosphoric acid at 160°C, then with sodium hydroxide base (NaOH) and surfactant at 40°C, and finally with a high-pressure deionized water spray rinse. Sapphire AMP has been demonstrated on both A- and C-plane sapphire workpieces. The mechanism of this etch process involves the reaction of the sapphire $({\rm Al_{2}}{\rm O_{3}})$(Al₂O₃) surface with sulfuric acid $({\rm H_{2}}{\rm SO_{4}})$(H₂SO₄) forming aluminum sulfate $[{{\rm Al}_2}{({{\rm SO}_4})_3}]$[Al₂(SO₄)₃], which has low solubility. The high phosphoric acid content in the first and second steps of sapphire AMP results in the efficient conversion of ${{\rm Al}_2}{({{\rm SO}_4})_3}$Al₂(SO₄)₃ to aluminum phosphate $({\rm AlPO_{4}})$(AlPO₄), which is very soluble, greatly reducing reaction product redeposition on the workpiece surface. Sapphire AMP is shown to expose sub-surface mechanical damage on the sapphire surface created during the grinding and polishing processes, whose etched morphology has either isotropic or anisotropic evolution depending on the nature of the initial surface damage. Sapphire AMP was also designed to remove the key known surface, laser absorbing precursors (namely, foreign chemical impurities, the fracture surface layer of preexisting sub-surface damage, and reaction product or foreign species redeposition or precipitation). Static and sliding indention induced surface microfractures on sapphire are shown after sapphire AMP to have a significant decrease in the fast photoluminescence intensity (a known metric for measuring the degree of laser damaging absorbing precursors). In addition, the onset of laser damage (at 351 nm 3 ns) on sapphire AMP treated workpieces was shown to increase in fluence from $\sim{4}$∼4 to $ \gt {9}.{5}\;{{\rm J/cm}^2}$>9.5J/cm². Finally, biaxial ball-on-ring mechanical tests on sapphire disks showed an increase in the failure stress from 340 MPa (with pre-existing 28 µm flaws) to $\sim{900}\;{\rm MPa}$∼900MPa after sapphire AMP, which is attributed to the blunting of the surface microfractures.

Precious little: Birth and death in the analytic process

What makes for the liveliness of a silence? How does liveliness prevail over destructivity in the unconscious encounter between two body-minds in the analytic process? What is being experienced unconsciously can go against the tendency to repeat, because the unconscious and conscious response of the analyst does not repeat the closing and/or the intrusiveness of the primary environment. The necessary receptivity required from the analyst and his/her unconscious capacity to accept an active passivation and a state of relative selflessness supposes that his/her narcissistic defences can be suspended to allow for working through rather than acting out. The unconsciousness of the analyst's mental life can be seen as a safeguard to the liveliness of the process. Just as his unconscious defences can sometimes hinder the ongoing development of the analytic process and elaboration. Interpretation only comes as an end result of a sustained contact and intercourse of the analyst's hopefully lively unconscious mental life and that of the analysand. Overcoming the risk that excitation prevails over tenderness is part and parcel of the constant unconscious working through of the analyst. The acting out works as a soul murder and tends to destroy the potential fecundity of the analytic encounter.

Suicide risk and social support in Australian resource sector employees: A cross-sectional study

This study examines the association between suicide risk and social support in Australian resource sector employees. We included 150 participants, who completed the Beck Hopelessness Scale and MOS-Social Support Survey. Data were analyzed using smallest space analysis and multidimensional scalogram analysis. The analysis identified four distinct regions, which were conceptualized as "confiding," "affection," "companionship," and "practical help." All of these components of social support were associated with hopelessness, which has important clinical implications as hopelessness is related to suicide risk. The results of this study also demonstrated that lower levels of social support, and greater sense of perceived hopelessness tended to lead to Australian resource workers seeking assistance from mental health professionals in the previous year. Attention should turn towards providing interventions that promote social support for employees in Australian resource industry.

Abstract P4-01-07: A comprehensive liquid biopsy in patients undergoing neoadjuvant therapy

Background: Precision medicine is revolutionizing breast cancer (BC) care. Comprehensive liquid biopsies are a tool for personalized care in patients with locally advanced breast cancer (LABC). Identifying robust biomarkers as part of a comprehensive liquid biopsy to predict response to treatment is of immense clinical interest.

Methods: After obtaining IRB approval, serial blood samples were collected from patients with LABC undergoing neoadjuvant therapy. Paired biopsies were collected prior to treatment and were sent to Foundation Medicine for next-generation sequencing (NGS). We used a sized-base microfilter technology to capture circulating tumor cells (CTCs) and circulating cancer associated fibroblasts (cCAFs). Patients with one or more CTCs or cCAFs were deemed positive for these tests. Additionally, in collaboration with Foundation Medicine, we extracted circulating tumor DNA (ctDNA) and we analyzed it using the FoundationACT platform. Patients with a detectable genomic alteration in their plasma were considered as having a positive ctDNA test. Our primary objective is to determine if a comprehensive liquid biopsy can serve as a prognostic marker of pathologic complete response (pCR).

Results: For this analysis we describe our findings in the initial blood draw of the first 18 patients enrolled. The mean age is 54 years (38-70). All patients who had their tumors sequenced had a detectable mutation. Consistent with the findings of others, we found TP53 mutations to be the most prevalent at 83.3%. We found that 44% of patients had ctDNA, 68.4% had cCAFs and 78.9% had CTCs. Many patients also had clusters of cells, consisting of one cell type, or co-clusters, consisting of both. 38.9% had CTC clusters, 16.7% had cCAF clusters and 16.7% had co-clusters (CTCs and cCAFs together). Some patients with CTCs did not have cCAFs and vice versa. The number of CTCs and cCAFS did not correlate with stage of disease or receptor status.

Conclusions: We describe a comprehensive liquid biopsy combining a sized-based microfilter technology for CTC and cCAFs identification and the FoundationACT platform for ctDNA analysis is feasible and these biomarkers can be detected in patients with LABC prior to the initiation of neoadjuvant therapy. Our study is accruing rapidly, and we will update our results with the longitudinal collection and the prognostic value of a comprehensive liquid biopsy at the time of the meeting.

Citation Format: Sandoval Leon AC, Medina Saenz K, Miller P, Benson A, Calfa C, Mahtani R, Slingerland J, Perez A, Vogel C, Valdes-Albini F, El-Ashry D, Lippman M. A comprehensive liquid biopsy in patients undergoing neoadjuvant therapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-01-07.

Abstract PD9-10: Circulating CAF/cancer stem cell co-clusters bolster breast cancer metastasis

Background: Metastatic disease is the primary cause of breast cancer (BC) mortality. Cancer associated fibroblasts (CAFs) are the majority of stroma in BC and critical players in BC malignancy. For example, CAFs are the main source of SDF-1, a prominent chemokine in the tumor microenvironment (TME) that also imparts stem cell-like characteristics to BC cells. Metastasis occurs due to the transport of circulating tumor cells (CTC) and clusters of CTCs through the vasculature. Stem-like CTCs and clusters have a greater propensity to establish metastasis. We recently identified circulating CAFs (cCAFs) in blood from patients with BC and in spontaneous, syngeneic, and xenograft mouse models of BC. cCAFs not only circulate individually, but are also found in clusters with CTCs. In this study, we examine the role of CAFs in promoting egress of stem-like CTCs (cCSCs), determine the capacity of stem-like CTCs to cluster with CAFs, and evaluate the involvement of CTC/cCAF clustering in augmenting BC metastasis.

Methods: Our model employs NSG mice with orthotopic xenograft implantation of BC cells, primary CAF cell lines, or co-implantation of BC and CAF cell lines. We used two different BC cell lines: the non-metastatic BC cell line, MCF-7, and the highly metastatic primary BC cell line, DT28. We also employed the MMTV-PyMT spontaneous model of BC metastasis, and we used BALB/c mice injected with syngeneic 4T1 or 67nR cells to evaluate cCAFs, CTCs, and cluster egress in preclinical models. Mice were sacrificed at specific time points, and cardiac blood was collected. Blood was filtered using the faCTChecker microfluidic filtration instrument (Circulogix). Filters were stained for IF and cCAFs, CTCs, cCSCs, and clusters were enumerated. Tumors from CAF co-injected mice were evaluated for their stem cell-like phenotype and re-implanted in mice to evaluate tumorigenicity and metastasis.

Results: In spontaneous, syngeneic, and orthotopic xenograft models of BC, cCAFs, CTCs, and cCAF/CTCs co-clusters appear early in tumor development. cCAF/CTC clusters increase in correlation with tumor burden and metastasis. Co-inoculation of CAFs with BC cells resulted in a significant increase in tumor progression, metastasis, and in a substantially higher number of both individual cells and clusters in circulation. Dissociated tumor cells from CAF co-injected tumors had a higher proportion of CD44+stem cell-like cells (CSCs), enhanced ALDH-1 expression, and enhanced mammosphere formation. CD44+ CSCs, individually and in clusters, are found early on in the circulation of mice injected with dissociated tumor cells from CAF co-injected tumors. Upon re-implantation of CAF co-injected dissociated tumor cells without CAFs, dissociated tumor cells showed enhanced tumorigenicity and malignancy.

Conclusion: CAFs are highly motile and cCAFs precede CTCs into circulation and can do so independently of tumor cells. CAFs sustain egress of tumor cells by augmenting malignancy and stemness of BC cells. cCAF clusters with the highly metastatic stem cell-like subset of CTCs bolster metastatic colonization. Targeting primary CAF function and/or cCAF/cCSC co-clusters may provide novel avenues to abrogate BC metastasis.

Citation Format: Sharma U, Miller P, Medina Saenz K, Picon-Ruiz M, Morata-Tarifa C, Spartz A, Troness B, Park DN, Seagroves TN, Slingerland JM, Lippman ME, El-Ashry D. Circulating CAF/cancer stem cell co-clusters bolster breast cancer metastasis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD9-10.

A comparison of screw versus drill and curettage epiphysiodesis to correct leg-length discrepancy

PURPOSE

To compare two common surgical techniques of epiphysiodesis: drill/curettage epiphysiodesis (PDED) versus cross screw epiphysiodesis (PETS). The hypothesis is that the two techniques have similar efficacy but demonstrate differences in length of hospital stay (LOS), time to return to activity and complication rates.

METHODS

A retrospective review of growing children and adolescents less than 18 years old who required an epiphysiodesis with leg-length discrepancy (LLD) of 2 cm to 6 cm with minimum two years of follow-up was conducted. Characteristics including age at surgery, gender, epiphysiodesis location, side, operative time, LOS and hardware removal were compared across treatment groups. LLD, expected growth remaining (EGR) and bone age were determined preoperatively and at most-recent visit. The correction ratio (change in EGR) was calculated along with a 95% confidence interval (CI) to assess if correction in leg length was achieved.

RESULTS

A total of 115 patients underwent epiphysiodesis in the femur (53%), tibia (24%) or a combination (24%). The cohort was 47% male, with a mean age of 12.6 years (7.7 to 17.7) at surgery. Median follow-up was 3.7 years (2.0 to 12.7). In all, 23 patients underwent PETS and 92 patients had PDED. Both treatment groups achieved expected LLD correction. There was no significant difference in median operative time, complication rates or LOS. PETS patients returned to activity at a mean 1.4 months (interquartile range (IQR) 0.7 to 2.1) while PDED patients returned at a mean 2.4 months (IQR 1.7 to 3) (p < 0.001).

CONCLUSION

Effectiveness in achieving expected correction, LOS and operative time are similar between screw and drill/curettage epiphysiodesis. Patients undergoing PETS demonstrated a faster return to baseline activity than patients with PDED.

LEVEL OF EVIDENCE

III.

A Novel Piperazine-Based Drug Lead for Cryptosporidiosis from the Medicines for Malaria Venture Open-Access Malaria Box

Cryptosporidiosis causes life-threatening diarrhea in children under the age of 5 years and prolonged diarrhea in immunodeficient people, especially AIDS patients. The standard of care, nitazoxanide, is modestly effective in children and ineffective in immunocompromised individuals. In addition to the need for new drugs, better knowledge of drug properties that drive in vivo efficacy is needed to facilitate drug development. We report the identification of a piperazine-based lead compound for Cryptosporidium drug development, MMV665917, and a new pharmacodynamic method used for its characterization. The identification of MMV665917 from the Medicines for Malaria Venture Malaria Box was followed by dose-response studies, in vitro toxicity studies, and structure-activity relationship studies using commercial analogues. The potency of this compound against Cryptosporidium parvum Iowa and field isolates was comparable to that against Cryptosporidium hominis Furthermore, unlike nitazoxanide, clofazimine, and paromomycin, MMV665917 appeared to be curative in a NOD SCID gamma mouse model of chronic cryptosporidiosis. MMV665917 was also efficacious in a gamma interferon knockout mouse model of acute cryptosporidiosis. To determine if efficacy in this mouse model of chronic infection might relate to whether compounds are parasiticidal or parasitistatic for C. parvum, we developed a novel in vitro parasite persistence assay. This assay suggested that MMV665917 was parasiticidal, unlike nitazoxanide, clofazimine, and paromomycin. The assay also enabled determination of the concentration of the compound required to maximize the rate of parasite elimination. This time-kill assay can be used to prioritize early-stage Cryptosporidium drug leads and may aid in planning in vivo efficacy experiments. Collectively, these results identify MMV665917 as a promising lead and establish a new method for characterizing potential anticryptosporidial agents.

Initial whole blood-based gene expression profile assays in mCRPC pts

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Background: Although second generation androgen receptor (AR) targeting therapy, abiraterone (Abi) and enzalutamide (enza), improve therapeutic effect for patients of mCRPC, acquired resistance occurs. Biomarkers are clearly needed to predict the efficacy of AR targeting drugs for mCRPC patients and much work is occurring on this important issue. Circulating tumor cells are attractive biomaterials because of non-invasive collecting methods. In this study, we assessed whole blood RNA as a non-invasive methodology to access biomarkers of potential interest. Methods: We used whole blood (~5mL) preserved in PAXgene tubes from 10 patients (pts) with mCRPC with acquired resistance following Abi and 11 controls without prostate cancer. Total RNA was extracted followed by qRT-PCR for assessment of 10 transcripts including ARV7, HOXB13, GHLR2, KLK3, KLK2, FOXA1, SchLAP1, KIF2C, MIA, and NCAM1. All amplicons were normalized to β-actin. Results: ARV7 (2/10), GRHL2 (2/10), HOXB13 (4/10), KLK3 (7/10), and KLK2 (4/10) amplicons were detected only in the mCRPC prostate pts. FOXA1 (7/10) and SchLAP1 (3/10) amplicons were detected in mCRPC pts at higher concentrations in mCRPC pts as compared to controls ( p< 0.001 and p = 0.02, respectively). In contrast, KIF2C (5/11), MIA (11/11), and NCAM1 (11/11) amplicons were present in pts but in lower concentrations in mCRPC as compared to controls (p = 0.03, p< 0.001, and p< 0.001, respectively). Conclusions: We identified 5 transcripts that can be detected from whole blood RNA assays only from PCa pts, additional transcripts were expressed at higher or lower concentrations as compared to controls. Although this is a small cohort, these findings highlight the potential role for whole blood RNA to assess mCRPC pts.

Abstract P2-01-10: Circulating CAF/CTC complexes and breast cancer metastasis

Background: Metastatic disease in breast cancer (BC) is the leading cause of cancer-related mortality among women worldwide. Synergy between cancer cells and non-cancer cells of the tumor microenvironment (TME) are vital for disease progression. Cancer associated fibroblasts (CAFs) are the major cell type in the stroma of BC and are critical mediators of tumor progression and metastasis. Transport of circulating tumor cells (CTCs) and CTC clusters through the vasculature seeds metastasis and clinical and preclinical studies demonstrate that CTC clusters have a higher metastatic potential than individual CTCs. More recently, circulating cancer stem cells (cCSCs) have been implicated as more metastatic than non-CSC CTCs. In our lab, we have demonstrated that CAFs also circulate (cCAFs). We have observed cCAFs in peripheral blood from breast cancer patients and in murine models of breast cancer. Furthermore, we have observed that cCAFs are present in circulation as both individual cells and as well as in complexes with CTCs. Given the integral role of CAFs in BC metastasis, we hypothesize that cCAFs complex with CTCs/cCSCs to bolster BC metastasis.

Methods: cCAF/CTC clusters were identified and enumerated from peripheral blood of patients with BC, and associations with clinical features and disease outcomes were evaluated. Blood was collected by cardiac puncture from PyMT mice from 4 weeks through to the presence of metastases (10 weeks) and cCAF/CTC clusters enumerated. We co-injected CAFs with MCF-7 cellsl into NSG mice, blood collected by cardiac puncture, and cCAF/CTC clusters were enumerated. At time of final sacrifice, tumors were removed and assessed for presence of CSCs. Using our established model of cCAF/CTC clustering in vitro we interrogated cCAF/CTC complexing with both metastatic and poorly metastatic BC cells.

Results: Circulating cCAFs/CTCs clusters are significantly increased in the blood of patients with advanced stage BC and associate not only with severity of disease but also with poorer clinical outcomes. In the spontaneous PyMT mouse model, the appearance of circulating cCAF/CTC clusters increased significantly as tumors grew but prior to metastasis. We demonstrate that metastatic BC cells form clusters with CAFs in vitro while non-metastatic BC cells do not form complexes with CAFs in vitro. Enriching for stem cells from MCF7 mammospheres, resulted in CAF/CSC clusters in vitro. In mice that were co-injected with non-metastatic MCF7 cells and CAFs from a TNBC/Basal-like BC (CAF23) we observed disease metastasis, an enrichment for cancer stem cell (CSC)-like CTCs, and the presence of circulating cCAF/MCF7-CSC clusters.

Conclusions: Circulating clusters of CTCs and cCAFs are characteristic, and potentially causative, of BC metastasis. Observations of cCAF/CTC clusters from preclinical and clinical samples are corroborated by our determination that the ability of BC cells to form complexes with CAFs in vitro is related to the intrinsic metastatic ability of the breast cancer cells. Both in vitro and in circulation, the BC cells in cCAF/cBC clusters are CSCs, so cCAF/cCSC clusters. Disrupting the formation of cCAF/CTC complexes may be a potential strategy to reduce treat or prevent breast cancer metastasis.

Citation Format: Miller P, Sharma U, Medina-Saenz K, Yeasky T, Picon-Ruiz M, Morata-Tarifa C, Seagroves T, Slingerland J, Lippman M, El-Ashry D. Circulating CAF/CTC complexes and breast cancer metastasis [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-01-10.