"To do so in a patient-centred way is not particularly lucrative": The effects of neoliberal health care on PrEP implementation and delivery

BACKGROUND

HIV pre-exposure prophylaxis (PrEP) is a highly effective biomedical intervention used by HIV-negative people to prevent HIV acquisition. Despite increased use of PrEP worldwide, several barriers to PrEP implementation have resulted in insufficient uptake, inadequate adherence, and frequent discontinuation. Our objective was to interrogate the social, political, and economic conditions shaping PrEP implementation and delivery among gay, bisexual, queer and other men who have sex with men (GBQM) in Ontario, Canada.

METHODS

Six focus groups and three interviews with 20 stakeholders in Ontario (e.g., healthcare professionals, clinicians, community-based organization staff, and government staff) were conducted between July and October 2021. Participants were asked about the personal, workplace, and structural factors shaping PrEP delivery strategies for GBQM. Transcripts were analyzed using reflexive thematic analysis informed by the political economy of PrEP and employed a critique of neoliberalism.

RESULTS

Participants critiqued the problematic arrangements of the current healthcare system in Canada. Neoliberal governmentality and policies have resulted in inequitable PrEP care by establishing funding structures prioritizing profit and requiring patients and providers to function as individual entrepreneurs. Consequently, healthcare disparities are compounded for marginalized peoples who lack the resources and capacity to navigate existing healthcare systems. Participants identified several pathways to improve the implementation of PrEP, including greater institutional and governmental supports for PrEP and healthcare, leveraging communities and collaboration, and moving beyond risk-based health frameworks.

CONCLUSION

Socio-political-economic changes reflecting post-neoliberal principles are needed to overcome existing barriers to PrEP care, and sexual and reproductive healthcare more broadly.

Gay, bisexual, and queer men's confidence in the Undetectable equals Untransmittable HIV prevention message: longitudinal qualitative analysis of the sexual decision-making of pre-exposure prophylaxis users over time

BACKGROUND

Our objective was to understand what gay, bisexual, and queer men (GBQM) who had experience using pre-exposure prophylaxis (PrEP) thought about the 'Undetectable equals Untransmittable' (U=U) message and how it informed their sexual decision-making over time.

METHODS

We conducted annual longitudinal qualitative interviews (2020-22) with 17 current or former PrEP users as part of a mixed-methods implementation science study examining barriers and facilitators to PrEP awareness, access, and adherence. Over 3years, 47 interviews were conducted with GBQM in Ontario, Canada. Interviews were transcribed verbatim and coded in NVivo following reflexive thematic analysis.

RESULTS

Participants' sexual health decision-making was informed by their confidence in biomedical HIV prevention and the person taking medication (i.e. themselves using PrEP versus a real/imagined person living with HIV (PLHIV)). Longitudinal narratives of U=U clustered around four overarching themes: (1) U=U confidence (i.e. increasing trust in U=U irrespective of their PrEP use); (2) PrEP confidence (i.e. accounts of self-reliance and PrEP as sufficient HIV protection); (3) combination confidence (i.e. trusting U=U and PrEP as a package); and (4) partner confidence (i.e. potential 'distrust' of U=U due to uncertainties about partners' medication adherence). Overall, men described increased sex with PLHIV over time, including some participants who, during earlier interviews, said they would 'never be comfortable' with serodifferent sexual partners.

CONCLUSIONS

GBQM's use of PrEP shaped how they thought about U=U and sex with PLHIV. Although many GBQM embraced treatment as prevention/U=U as significant to their sexual lives, longitudinal analysis revealed its varied and uneven adoption across participants and time.

Injectable Pre-Exposure Prophylaxis for HIV Prevention: Perspectives on the Benefits and Barriers from Gay, Bisexual, and Queer Men and Health System Stakeholders in Ontario, Canada

One hope surrounding long-acting HIV pre-exposure prophylaxis (PrEP) is reaching new users who could most benefit, as well as improving the experiences of oral PrEP users who may desire to switch modalities. Gay, bisexual, queer, and other men who have sex with men (GBQM) continue to make up over half of new HIV diagnoses in Canada, and oral PrEP uptake has plateaued among this population. Approval of injectable PrEP is anticipated, but there is a paucity of research to inform health promotion and implementation. Between June and October 2021, we conducted 22 in-depth interviews with GBQM oral PrEP users and non-PrEP users living in Ontario, Canada. We also conducted small focus groups or individual interviews with 20 key stakeholders (health care providers, public health officials, community-based organization staff). Interviews were audio recorded, transcribed verbatim, and analyzed in NVivo using thematic analysis. Only about one-third of GBQM had heard of injectable PrEP. Many PrEP users perceived greater convenience, adherence, and confidentiality with injectable PrEP. Some PrEP users did not anticipate switching because of needle discomfort or feeling more "in control" with oral PrEP. None of the non-PrEP users said that injectable PrEP would make them start PrEP. Injectable PrEP may offer additional convenience for GBQM; however, it did not appear to affect participants' PrEP decision-making significantly. Stakeholders noted that injectable PrEP may improve access, support adherence, and benefit marginalized groups. Some clinicians expressed concerns about the time/personnel required to make injectable PrEP available. System-level challenges in implementing injectable PrEP, including cost, must also be addressed.

Human Papillomavirus Vaccine

Cervical cancer is the fourth most common cancer in women worldwide with immense associated morbidity and mortality. Although most of the cervical cancer cases are caused by the human papillomavirus (HPV) and can effectively be prevented by HPV vaccination, vaccination unfortunately remains underused on a global scale with vast inequities in distribution. A vaccine as a tool to prevent cancer, cervical and others, is largely unprecedented. Then why do HPV vaccination rates globally remain so low? This article explores the burden of disease, development of the vaccine and its subsequent uptake, cost-effectiveness, and associated equity issues.

HIV pre-exposure prophylaxis (PrEP) should be free across Canada to those meeting evidence-based guidelines

HIV pre-exposure prophylaxis (PrEP) should be free across Canada for all those who meet evidence-based guidelines. PrEP is a highly effective tool for preventing HIV acquisition that has been approved for use in Canada since 2016. However, without public drug plans or private insurance, generic PrEP costs approximately $200 to $250 CAD monthly. Current PrEP programs across Canada are a confusing patchwork system with variability in coverage and prohibitive co-payments, making PrEP too expensive for many equity-deserving groups. However, publicly funded PrEP programs are demonstrated to be cost-effective and even cost-saving by reducing the long-term healthcare expenditures associated with managing HIV. PrEP is not just an individual-level clinical tool. It is a public health intervention. Alongside “treatment as prevention,” PrEP is an important population-level strategy for eliminating new HIV infections in Canada and can play a role in helping to address complex health inequities affecting communities highly affected by HIV. Navigating drug coverage for patients consumes time and resources among healthcare providers that could be spent helping to improve other social determinants of health. Affordability will remain the foremost barrier to PrEP access until PrEP is made free to all those who meet evidence-based guidelines.

Evaluation of 5 Fraction Stereotactic Body Radiation Therapy (SBRT) for Osseous Renal Cell Carcinoma Metastases

OBJECTIVES

The best fractionation for stereotactic body radiotherapy (SBRT) in renal cell carcinoma (RCC) metastases has not been well defined. In addition, the literature on outcomes using 5-fraction SBRT in the setting of osseous metastases has not been well reported.

MATERIALS AND METHODS

Thirty-nine patients with 69 RCC osseous metastases were treated using 5-fraction SBRT at a single institution using 2 dose-fractionation schemes. Overall survival and local-control (LC) outcomes of the 2 fractionation schemes were studied using Kaplan-Meier curves.

RESULTS

Of the 69 lesions included in the study, 20 were treated with 30 grays (Gy) in 5 fractions and 49 were treated with 40 Gy in 5 fractions. The median age of patients at diagnosis was 58.4 years. The 1-year LC rate for all treated lesions was 85.5% (59/69) with an LC of 90% (18/20) for lesions receiving 30 Gy and 83.7% (41/49) in lesions receiving 40 Gy. There was no statistically significant difference in 1-year LC rate between the 2 fractionation schemes (P-value, 0.553).

CONCLUSIONS

Patients with osseous RCC metastases undergoing 5 fractions of SBRT had favorable LC outcomes. There was no difference in survival or LC between the 40 Gy and 30 Gy treatment arms.

New and Interesting Fungi. 5

Nine new genera, 17 new species, nine new combinations, seven epitypes, three lectotypes, one neotype, and 14 interesting new host and / or geographical records are introduced in this study. New genera: Neobarrmaelia (based on Neobarrmaelia hyphaenes), Neobryochiton (based on Neobryochiton narthecii), Neocamarographium (based on Neocamarographium carpini), Nothocladosporium (based on Nothocladosporium syzygii), Nothopseudocercospora (based on Nothopseudocercospora dictamni), Paracamarographium (based on Paracamarographium koreanum), Pseudohormonema (based on Pseudohormonema sordidus), Quasiphoma (based on Quasiphoma hyphaenes), Rapidomyces (based on Rapidomyces narthecii). New species: Ascocorticium sorbicola (on leaves of Sorbus aucuparia, Belgium), Dactylaria retrophylli (on leaves of Retrophyllum rospigliosii, Colombia), Dactylellina miltoniae (on twigs of Miltonia clowesii, Colombia), Exophiala eucalyptigena (on dead leaves of Eucalyptus viminalis subsp. viminalis supporting Idolothrips spectrum, Australia), Idriellomyces syzygii (on leaves of Syzygium chordatum, South Africa), Microcera lichenicola (on Parmelia sulcata, Netherlands), Neobarrmaelia hyphaenes (on leaves of Hyphaene sp., South Africa), Neobryochiton narthecii (on dead leaves of Narthecium ossifragum, Netherlands), Niesslia pseudoexilis (on dead leaf of Quercus petraea, Serbia), Nothocladosporium syzygii (on leaves of Syzygium chordatum, South Africa), Nothotrimmatostroma corymbiae (on leaves of Corymbia henryi, South Africa), Phaeosphaeria hyphaenes (on leaves of Hyphaene sp., South Africa), Pseudohormonema sordidus (on a from human pacemaker, USA), Quasiphoma hyphaenes (on leaves of Hyphaene sp., South Africa), Rapidomyces narthecii (on dead leaves of Narthecium ossifragum, Netherlands), Reticulascus parahennebertii (on dead culm of Juncus inflexus, Netherlands), Scytalidium philadelphianum (from compressed air in a factory, USA). New combinations: Neobarrmaelia serenoae, Nothopseudocercospora dictamni, Dothiora viticola, Floricola sulcata, Neocamarographium carpini, Paracamarographium koreanum, Rhexocercosporidium bellocense, Russula lilacina. Epitypes: Elsinoe corni (on leaves of Cornus florida, USA), Leptopeltis litigiosa (on dead leaf fronds of Pteridium aquilinum, Netherlands), Nothopseudocercospora dictamni (on living leaves of Dictamnus albus, Russia), Ramularia arvensis (on leaves of Potentilla reptans, Netherlands), Rhexocercosporidium bellocense (on leaves of Verbascum sp., Germany), Rhopographus filicinus (on dead leaf fronds of Pteridium aquilinum, Netherlands), Septoria robiniae (on leaves of Robinia pseudoacacia, Belgium). Lectotypes: Leptopeltis litigiosa (on Pteridium aquilinum, France), Rhopographus filicinus (on dead leaf fronds of Pteridium aquilinum, Netherlands), Septoria robiniae (on leaves of Robinia pseudoacacia, Belgium). Neotype: Camarographium stephensii (on dead leaf fronds of Pteridium aquilinum, Netherlands). Citation: Crous PW, Begoude BAD, Boers J, Braun U, Declercq B, Dijksterhuis J, Elliott TF, Garay-Rodriguez GA, Jurjević Ž, Kruse J, Linde CC, Loyd A, Mound L, Osieck ER, Rivera-Vargas LI, Quimbita AM, Rodas CA, Roux J, Schumacher RK, Starink-Willemse M, Thangavel R, Trappe JM, van Iperen AL, Van Steenwinkel C, Wells A, Wingfield MJ, Yilmaz N, Groenewald JZ (2022) New and Interesting Fungi. 5. Fungal Systematics and Evolution 10: 19-90. doi: 10.3114/fuse.2022.10.02.

Molecular Solid Tumor Algorithm – Simplified Patient-Centric/Cost-Effective Approach by Pathologists

Introduction/Objective

The process from the time the patient is diagnosed with cancer and receives their first treatment is complex and time-consuming. It requires adherence to national comprehensive cancer network (NCCN) guidelines; is challenged with limited tissue, how and when to order tests, and reimbursement timelines with pre- authorizations. We evaluated the role of the pathologists, who are an integral part of patient care, along with oncologists and surgeons.

Methods/Case Report

254 cases from various types of solid tumors (paraffin-embedded blocks) were collected from several pathology departments. Tests (two panels NGS-DNA/RNA expression, FISH, PD-L1, and IHC) were ordered as early as on the day of diagnosis to as late as 18 months following the diagnosis. Cancer cases reviewed were Colo-Rectal (72), Lung (48), Breast (24), Gastric (10), CNS (8), Melanoma (4), Head/Neck (20), GU (16), Sarcomas (8), Thyroid (6), Hepatic (8), Female Genital Tract (7) and Unknown Primary (23).

Results (if a Case Study enter NA)

We evaluated pathology reports, identified blocks, reviewed H&E slides, utilized NCCN guidelines in collaboration with oncologists. Tests were ordered using established billing criteria. Following tests were performed: PD-L1 (190 - 75%), FISH (50 - 20%), and NGS – two simple panel approach (215 - 85%). Using the aforesaid methods, our NGS results were successful in >95%. We were able to identify actionable and prognostic mutations in >80% of tumors.

Conclusion

Our algorithm has been designed considering NCCN guidelines and are updated frequently with new therapeutic targets and actionable mutations. The emphasis is to conserve diagnostic tissue and ensure timely ordering of tests as medically necessary. This can be adopted by pathologists in conjunction with clinical information, pathology reports, and be used as a part of diagnostic workups to reduce delays in treatment, avoid tissue loss, utilize current billing (inpatient/outpatient) practices, pre-authorization and eventually improving patient care as well as reduce overall healthcare costs.

Impact of cardiac resynchronisation therapy in patients with cardiac sarcoidosis

Background

Implantation of a device is usually required in cardiac sarcoidosis (CS) patients presenting with advanced conduction abnormalities or ventricular arrhythmias. A cardiac resynchronisation therapy (CRT) device is often chosen in patients with concomitant left ventricular systolic impairment. The role of CRT in CS is not well established.

Purpose

To describe the cohort of CS patients with CRT device in situ in our hospital focusing on the short-term effect in serial echocardiography and long-term outcomes on morbidity and mortality.

Methods

All consecutive CS patients with a CRT device in situ were identified in our CS database (2005–2022). A confident CS diagnosis was provided after review of all relevant clinical and imaging baseline data in our CS multi-disciplinary meeting and a consensus decision for CRT-D implantation was made based on international guidelines. All patients were followed up for at least 6 months with serial echocardiography. Serial data regarding symptoms, rhythm disturbance and echocardiographic parameters were obtained and comparisons were performed using Wilcoxon signed rank test.

Results

A total of 51 CS patients with CRT-D were identified (mean age: 57±10 years old). Patients were male predominant (64.7%) and Caucasian in origin (86.2%). Extra-cardiac sarcoidosis was confirmed histologically in 33 (64.7%) patients. The prevalence of smoking, diabetes, hypertension and ischaemic heart disease was 27.5%, 21.6%, 49.0% and 7.8% respectively. At the time of device implantation or during follow-up, 43 (84.3%) patients were found to have active cardiac sarcoidosis on cardiac PET.

Post CRT implantation there was a significant difference in LV ejection fraction (35.9±15.0% vs 42.2±14.1%, p<0.001), LV end-systolic diameter (4.90±1.46 cm vs 4.62±1.32 cm, p=0.012) and LV end-diastolic diameter (5.99±1.18 cm vs 5.66±1.06 cm, p<0.001). No significant changes were observed in the right ventricular function (p=0.09) and severity of mitral regurgitation (p=0.40). There was one patient who experienced acute heart failure decompensation admission within six months of CRT-D implantation. The New York Heart Association (NYHA) class improved in 26 patients (51.0%), worsened in 4 (7.8%) patients and remained the same in 21 (41.2%) patients at 6 months post CRT-implantation. During the mean follow up of 47.6 months, the composite end-point of death and cardiac transplantation was reached in 9 (17.6%) patients (8 deaths and 1 cardiac transplantation). 5 patients had major complications including a large haematoma, a small atrio-septal defect, haemothorax, device associated endocarditis and lead fracture. Minor wound infections were seen in 3 patients and 4 patients received inappropriate shock or anti-tachycardia pacing.

Conclusions

CRT in cardiac sarcoidosis patients is associated with short-term improvement in LV remodelling and functional status but over a four year follow up, morbidity and mortality are common.

Funding Acknowledgement

Type of funding sources: None.

"What other choices might I have made?": Sexual Minority Men, the PrEP Cascade and the Shifting Subjective Dimensions of HIV Risk

The PrEP Cascade is a dominant framework for investigating barriers to HIV pre-exposure prophylaxis (PrEP), an HIV prevention tool. We interviewed 37 PrEP users and 8 non-PrEP users in Ontario and British Columbia, Canada, about their decision-making through the Cascade. Participants were HIV-negative gay, bisexual, and queer men (GBQM). The data were analyzed using thematic analysis. PrEP decision-making was based on pragmatic considerations (logistics, costs, and systemic barriers), biomedical considerations (efficacy, side-effects, and sexually transmitted infections), and subjective considerations (identity, politics, and changing sexual preferences). Affective attachments to established versions of "safer sex" (condoms and serosorting) made some GBQM less likely to try PrEP. Some GBQM expressed increased social expectations to use PrEP, have condomless sex, and serodifferent sex. These findings support offering PrEP at no-cost, offering individualized counseling and community-based opportunities to discuss PrEP use and changing sexual practices, and improving communication on the manageability of PrEP side-effects.

DESIGN OPTIMIZATION OF THE HOLOS-QUAD MICRO-REACTOR CONCEPT

The Holos-Quad micro-reactor concept is proposed by HolosGen LLC to generate 22 MWt with a lifetime of approximately 8 effective full power years (EFPYs) for civilian applications. The design is based on a very innovative high-temperature gas-cooled reactor concept using four Subcritical Power Modules (SPMs) that fit into one commercial 40-foot transport ISO container. A rigorous design approach was employed in order to ensure that all input parameters were fully investigated and the best solutions possible were considered. The first step of this approach consisted of properly defining the Holos-Quad design problem by identifying the design objectives, the operational constraints, and the input parameters. In the second step, a sensitivity analysis was performed to enable a preliminary investigation of the input parameters to identify the correlations among input and output variables. Finally, the design optimization was performed in the third step, employing a genetic algorithm to effectively explore the highly constrained input parameters and find global optimal solutions. The multi-objective optimization identified various core solutions that would be optimum solutions for different types of applications. For applications where economics matters less and the ease of transportation matters more, a core weight of ~15 tons could achieve a lifetime of ~3.5 EFPYs. For applications where economics matters more and the ease of transportation matters less, a lifetime of 8.3 EFPYs could be achieved with a total core weight of ~26.7 tons.

NEUTRONIC BENCHMARK ON HOLOS-QUAD MICRO-REACTOR CONCEPT

The Holos-Quad micro-reactor concept is proposed by HolosGen LLC for civilian applications to generate 22 MWt with a lifetime of approximately 8 effective full power years (EFPYs). The design is based on a very innovative high-temperature gas-cooled reactor concept using four Subcritical Power Modules (SPMs) that fit into one commercial 40-foot transport ISO container. Neutronics benchmarks were developed based on a preliminary version of the Holos-Quad design to confirm feasibility of the neutronics design of this non-traditional high temperature gas-cooled (HTGR)-type micro-reactor concept. Calculations were performed using Monte Carlo codes (SERPENT and OpenMC) as well as the PROTEUS high-fidelity deterministic code for two exercises based on a unit cell model and a full core model. The results obtained showed good agreement with all of the evaluated parameters for the unit cell problem and the full core problem. SERPENT and OpenMC display consistently good agreement in eigenvalue within 150 pcm for the unit cell benchmark and less than 270 pcm for the full core benchmark. PROTEUS eigenvalues showed relatively larger differences but still reasonable agreement with the SERPENT solutions. For the depletion benchmark, the observed eigenvalue differences between SERPENT and OpenMC were within 300 pcm throughout the depletion up to 100 GWd/MT, ensuring that the two codes used equivalent input parameters such as the recoverable heat values for fission reactions. This benchmark exercise confirms the neutronic feasibility and core performance of the preliminary Holos-Quad design.

Treatment of a heart base tumor and chylothorax with endovascular stent, stereotactic body radiation therapy, and a tyrosine kinase inhibitor in a dog

An 8-year-old 28-kg male castrated rough collie was evaluated for persistent chylothorax secondary to right atrial mass. Cardiac ultrasound and computed tomography revealed a right atrial intra- and extraluminal mass with partial obstruction of the cranial vena cava and secondary chylothorax. Vascular stent placement was elected to alleviate cranial vena cava obstruction and secondary chylothorax. An 18 mm × 180 mm self-expanding stent was deployed in the region of the stricture, spanning the cranial vena cava and right atrium. An intrathoracic drainage catheter and subcutaneous port were placed within the right hemithorax, and antiplatelet therapy was initiated. Four weeks later, the dog underwent stereotactic body radiation therapy. Three months following treatment, the dog was diagnosed with supraventricular tachycardia and received antiarrhythmic therapy and antiangiogenic/antiproliferative medication (Palladia™). Subsequent evaluations confirmed the resolution of arrhythmia and pleural effusion. Combined vascular stent placement and stereotactic body radiation therapy for the treatment of a right atrial intraluminal and extraluminal mass leading to cranial vena cava compression and subsequent chylothorax may lead to long-term survival. A good outcome was achieved in this patient due to resolution of pleural effusion, as well as cytoreduction and presumably delayed progression of tumor growth.

Ranking of non-coding pathogenic variants and putative essential regions of the human genome

A gene is considered essential if loss of function results in loss of viability, fitness or in disease. This concept is well established for coding genes; however, non-coding regions are thought less likely to be determinants of critical functions. Here we train a machine learning model using functional, mutational and structural features, including new genome essentiality metrics, 3D genome organization and enhancer reporter data to identify deleterious variants in non-coding regions. We assess the model for functional correlates by using data from tiling-deletion-based and CRISPR interference screens of activity of cis-regulatory elements in over 3 Mb of genome sequence. Finally, we explore two user cases that involve indels and the disruption of enhancers associated with a developmental disease. We rank variants in the non-coding genome according to their predicted deleteriousness. The model prioritizes non-coding regions associated with regulation of important genes and with cell viability, an in vitro surrogate of essentiality.

Whole genome sequencing (WGS) holds promise to solve a subset of Mendelian disease cases for which exome sequencing did not provide a genetic diagnosis. Here, Wells et al. report a supervised machine learning model trained on functional, mutational and structural features for rank-scoring and interpreting variants in non-coding regions from WGS.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Skew in ovarian activation depends on domicile size in phyllode-glueing thrips

Costs and benefits of group living are a fundamental topic in behavioural ecology. Resource availability affects individuals’ breeding prospects alone and in groups, as well as how reproduction is distributed within groups (“reproductive skew”). Here, in facultatively social thrips, we provide correlational evidence that breeding resources are associated with (1) whether solitary or social living is favoured, and (2) the degree of ovarian skew. Dunatothrips aneurae (Thysanoptera, Phlaeothripidae) cooperatively build silk “domiciles” on Australian Acacias, feeding exclusively from internal phyllode surfaces. Per capita productivity scaled differently with group size depending on domicile volume — females in small domiciles did better alone than in groups, whereas in large domiciles single and group-nesting females did equally well. Ovarian dissections revealed that in small domiciles some females were nonreproductive, indicating ovarian (i.e. reproductive) skew. Skew increased as domicile size decreased and group size increased. Breeders had smaller oocyte volume in smaller domiciles, especially those containing nonreproductives. These findings suggest group formation and reproductive skew in D. aneurae may be influenced by reproductive competition for breeding resources. Nonreproductive females in small domiciles may be reproductively suppressed, subfertile, or accumulating resources to reproduce.

Abstract P1-01-20: Adjuvant statin therapy efficacy is dictated by tumor dormancy and statin lipophilicity in ex vivo and in vivo models of metastatic breast cancer

Metastasis in breast cancer patients heralds mortality, as disseminated disease is generally chemoresistant. After tumor cells reach the ectopic tissue, they undergo an epithelial reversion to enter a period of quiescence, termed dormancy, which may last for decades before outgrowing again as mesenchymal/dedifferentiated masses. Thus, long-term, relatively non-toxic interventions that prevent metastatic outgrowth are needed to treat this mortal stage of tumor progression.

Epidemiological analyses have suggested that statin usage, for cardiovascular indications, is correlated with a reduction in clinically-evident metastatic (though not in incidence of primary) breast cancer. The goal of this study is to demonstrate this is due to statins suppressing breast cancer cell proliferation and keeping the micrometastases in the dormant state.

We have found that atorvastatin and simvastatin limit the growth of some cancer cell lines, but not others. The sensitive lines were marked by lacking surface E-cadherin, the hallmark of the mesenchymal phenotype. When E-cadherin is downregulated on epithelial tumor cells, the cells become growth inhibited by the statins. Furthermore, this is a direct effect, as we now have shown that hydrophilic statins are relatively ineffective compared to the membrane permeant lipophilic statins as tumor cells generally lack the transporters that enable these drugs to gain access to the cells.

To determine whether the statins target the emergent metastatic tumor cells, we are using an all human microphysiological system (MPS) of the most common site for metastases, the liver. Briefly, a micro-hepatic tissue is established by seeding primary human liver cells in a porous scaffold subject to a physiological flow. RFP-labeled breast cancer cells are seeded into these microtissues and examined weeks later. Liver function and health are monitored by clinical chemistry assays performed on supernatant samples. We have previously shown that this system robustly reproduces tumor dormancy. Initial studies suggest that statins suppress the emergence of dormant tumor cells when challenged by stressors that lead to outgrowth. Additionally, atorvastatin suppresses proliferation of mesenchymal but not epithelial breast cancer cells in intrasplenic and mammary fat pad injection models for breast cancer metastasis to the liver and lung respectively. As 26% of adults currently take a statin for other medical conditions, these studies may suggest the best statin to use in the context of maintaining breast cancer dormancy long-term and delaying or avoiding the morbid emergence.

Citation Format: Beckwitt CH, Clark AM, Warita K, Oltvai ZN, Wells A. Adjuvant statin therapy efficacy is dictated by tumor dormancy and statin lipophilicity in ex vivo and in vivo models of metastatic breast cancer [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 P1-01-20.

Systematic Quantification of Population Cell Death Kinetics in Mammalian Cells

Cytotoxic compounds are important drugs and research tools. Here, we introduce a method, scalable time-lapse analysis of cell death kinetics (STACK), to quantify the kinetics of compound-induced cell death in mammalian cells at the population level. STACK uses live and dead cell markers, high-throughput time-lapse imaging, and mathematical modeling to determine the kinetics of population cell death over time. We used STACK to profile the effects of over 1,800 bioactive compounds on cell death in two human cancer cell lines, resulting in a large and freely available dataset. 79 potent lethal compounds common to both cell lines caused cell death with widely divergent kinetics. 13 compounds triggered cell death within hours, including the metallophore zinc pyrithione. Mechanistic studies demonstrated that this rapid onset lethal phenotype was caused in human cancer cells by metabolic disruption and ATP depletion. These results provide the first comprehensive survey of cell death kinetics and analysis of rapid-onset lethal compounds.

A Pathway to Personalizing Therapy for Metastases Using Liver-on-a-Chip Platforms

Metastasis accounts for most cancer-related deaths. The majority of solid cancers, including those of the breast, colorectum, prostate and skin, metastasize at significant levels to the liver due to its hemodynamic as well as tumor permissive microenvironmental properties. As this occurs prior to detection and treatment of the primary tumor, we need to target liver metastases to improve patients' outcomes. Animal models, while proven to be useful in mechanistic studies, do not represent the heterogeneity of human population especially in drug metabolism lack proper human cell-cell interactions, and this gap between animals and humans results in costly and inefficient drug discovery. This underscores the need to accurately model the human liver for disease studies and drug development. Further, the occurrence of liver metastases is influenced by the primary tumor type, sex and race; thus, modeling these specific settings will facilitate the development of personalized/targeted medicine for each specific group. We have adapted such all-human 3D ex vivo hepatic microphysiological system (MPS) (a.k.a. liver-on-a-chip) to investigate human micrometastases. This review focuses on the sources of liver resident cells, especially the iPS cell-derived hepatocytes, and examines some of the advantages and disadvantages of these sources. In addition, this review also examines other potential challenges and limitations in modeling human liver.

Implementation of the Needs Assessment Tool for patients with interstitial lung disease (NAT:ILD): facilitators and barriers

A Needs Assessment Tool (NAT) was developed previously to help clinicians identify the supportive/palliative needs of people with interstitial lung disease (ILD) (NAT:ILD). This letter presents barriers and facilitators to clinical implementation. Data from (1) a focus group of respiratory clinicians and (2) an expert consensus group (respiratory and palliative clinicians, academics, patients, carers) were analysed using Framework Analysis. Barriers related to resources and service reconfiguration, and facilitators to clinical need, structure, objectiveness, flexibility and benefits of an ‘aide-memoire’. Identified training needs included communication skills and local service knowledge. The NAT:ILD was seen as useful, necessary and practical in everyday practice.

A liver microphysiological system of tumor cell dormancy and inflammatory responsiveness is affected by scaffold properties

Distant metastasis is the major cause of breast cancer-related mortality, commonly emerging clinically after 5 or more years of seeming 'cure' of the primary tumor, indicating a quiescent dormancy. The lack of relevant accessible model systems for metastasis that recreate this latent stage has hindered our understanding of the molecular basis and the development of therapies against these lethal outgrowths. We previously reported on the development of an all-human 3D ex vivo hepatic microphysiological system that reproduces several features of liver physiology and enables spontaneous dormancy in a subpopulation of breast cancer cells. However, we observed that the dormant cells were localized primarily within the 3D tissue, while the proliferative cells were in contact with the polystyrene scaffold. As matrix stiffness is known to drive inflammatory and malignant behaviors, we explored the occurrence of spontaneous tumor dormancy and inflammatory phenotype. The microphysiological system was retrofitted with PEGDa-SynKRGD hydrogel scaffolding, which is softer and differs in the interface with the tissue. The microphysiological system incorporated donor-matched primary human hepatocytes and non-parenchymal cells (NPCs), with MDA-MB-231 breast cancer cells. Hepatic tissue in hydrogel scaffolds secreted lower levels of pro-inflammatory analytes, and was more responsive to inflammatory stimuli. The proportion of tumor cells entering dormancy was markedly increased in the hydrogel-supported tissue compared to polystyrene. Interestingly, an unexpected differential response of dormant cells to varying chemotherapeutic doses was identified, which if reflective of patient pathophysiology, has important implications for patient dosing regimens. These findings highlight the metastatic microphysiological system fitted with hydrogel scaffolds as a critical tool in the assessment and development of therapeutic strategies to target dormant metastatic breast cancer.

Abstract P2-05-19: Breast cancer dormancy, re-emergence, and treatment

Breast cancer (BrCa) mortality continues to result predominately from distant metastases that can emerge years after successful treatment of the primary disease. Metastatic resistance to agents that eradicate the primary mass is likely due to protection from the metastatic microenvironment and the quiescent state of dormant BrCa cells. Advancements for the treatment of metastatic tumors have been made, but significant progress has been hampered by the lack of relevant model systems, particularly for dormancy. We address this gap with an innovative all-human 3D liver microphysiological system (MPS). The liver is both a major site for BrCa metastasis (and other solid tumors) and the primary site of drug metabolism and limiting toxicities, an important consideration in evaluating cancer therapy efficacy and availability.

Primary hepatocytes and non-parenchymal cells (NPC) from human liver resections were seeded into the MPS. Following tissue formation on day 3, tagged BrCa cells were seeded and allowed a minimum of 4 days to integrate into the tissue before interventions were initiated. On day 7, chemotherapy treatment of micrometastases was initiated for 72h. Cultures were allowed 3 days to recover before the MPS was challenged with inflammatory factors (LPS/EGF) for 48h. BrCa cells were then re-treated with chemotherapy (either the same or alternate therapy) on day 21 for 72h. Hepatocyte function and injury were measured by urea, AST, ALT, A1AT, fibrinogen and CYP P450 assays. BC proliferation was monitored by quantification, Ki67 staining, and EdU incorporation. Communication networks within the metastatic microenvironment during different stages of metastatic BrCa progression were identified using Luminex assays (55 analytes).

The metastatically aggressive MDA-MB-231 BrCa cells demonstrated growth attenuation after 12d of culture in a subpopulation of cells (Ki67-/EdU-). Treatment of BrCa cells with doxorubicin for 72h eradicates the cycling cells, leaving behind a dormant cell population (Ki67-/EdU-) that can be subsequently stimulated to cycle by addition of inflammatory stimuli. A second dose of doxorubicin or cisplatin reduced the BrCa load but did not eradicate the BrCa. Luminex analysis of culture supernatants identified signaling molecules potentially involved in metastatic progression. In addition, we present the use of adjuvant therapy in the MPS to prevent this outgrowth of the dormant tumor cells.

In parallel, we have piloted hydrogel scaffolds that better support tissue formation and produce signals consistent with a healthier liver physiology. Hydrogels enhanced MDA-MB-231 cell entry into dormancy, resulting in reduced efficacy of doxorubicin treatment with greater persistence of tumor load.

The MPS provides a mechanism to close the gap in understanding metastatic dormancy. We demonstrate spontaneous dormancy for the first time in an all-human system and mimicked the dormancy and outgrowth observed in patients. Namely, that dormant BrCa are resistant to chemotherapy and can be stimulated to reemerge following an inflammatory insult. The completion of these studies will provide insights into the tumor biology of metastatic seeding, dormancy, and re-emergence and provide an accessible tool for testing therapeutics against metastatic BrCa in a metabolically competent system capable of evaluating dose-limiting toxicity.

Citation Format: Beckwitt C, Wheeler SE, Clark AM, Pillai VC, Young CL, Stolz DB, Lauffenburger DA, Venkataramanan R, Griffith LG, Wells A. Breast cancer dormancy, re-emergence, and treatment. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-05-19.

Spontaneous dormancy of metastatic breast cancer cells in an all human liver microphysiologic system

Background:

Metastatic outgrowth in breast cancer can occur years after a seeming cure. Existing model systems of dormancy are limited as they do not recapitulate human metastatic dormancy without exogenous manipulations and are unable to query early events of micrometastases.

Methods:

Here, we describe a human ex vivo hepatic microphysiologic system. The system is established with fresh human hepatocytes and non-parenchymal cells (NPCs) creating a microenvironment into which breast cancer cells (MCF7 and MDA-MB-231) are added.

Results:

The hepatic tissue maintains function through 15 days as verified by liver-specific protein production and drug metabolism assays. The NPCs form an integral part of the hepatic niche, demonstrated within the system through their participation in differential signalling cascades and cancer cell outcomes. Breast cancer cells intercalate into the hepatic niche without interfering with hepatocyte function. Examination of cancer cells demonstrated that a significant subset enter a quiescent state of dormancy as shown by lack of cell cycling (EdU⁻ or Ki67⁻). The presence of NPCs altered the cancer cell fraction entering quiescence, and lead to differential cytokine profiles in the microenvironment effluent.

Conclusions:

These findings establish the liver microphysiologic system as a relevant model for the study of breast cancer metastases and entry into dormancy.