Abstract P4-09-08: Shared-patient physician networks and their impact on the uptake of genomic testing in early-stage breast cancer

Background: Oncotype DX (ODX) or 21-gene recurrence score genomic testing is used to stratify risk and determine appropriate treatment in women with early-stage breast cancer (BC). Diffusion of ODX by way of physician networks has not been studied.

Objective: To determine the association between physician network connections, defined by shared patients, and the use of ODX testing.

Methods: SEER-Medicare claims from 2008-2012 were used to identify a cohort of woman with a diagnosis of BC from registry/ICD codes, continuously enrolled in Medicare fee-for-service Part A and B one year prior to and one year following diagnosis. We identify receipt of ODX from the associated CPT code, claim reimbursement, and performing NPI. To look at the influence of network connections on ODX use, we split the study into two time periods: early adoption from 2008-2009, and late from 2010-2012. Medical oncologists with a BC-related claim in the cohort above, and any rendered BC-related service are considered 'connected' if they shared two or more BC patients. Analyses describe these connections and explore the association between connectedness to an early adopting medical oncologist and ODX use in parallel physician and patient-level analyses using generalized linear mixed models with a hospital referral region-specific random effect. Models control for physician and patient-level characteristics where applicable.

Results:24,463 women met study criteria; 12,874 were diagnosed with BC in the early adoption time period (1,790 received ODX) and 11,589 were diagnosed in the late period (2,334 received ODX). 2,073 medical oncologists treated these patients from 2008-2009. The mean number of BC patients treated per medical oncologist was 86.8 during the early adoption period, and medical oncologists had a median number of peer connections of 11 (IQR: 7-18). Early adopting medical oncologists had higher numbers of peer connections and higher average patient counts than non-early adopters. A higher percentage of female medical oncologists were early adopters (39%) then male medical oncologists (33%) (p<0.02). Among non-early adopting oncologists, peer connection to at least two early adopting providers in 2008-2009 is associated with a 3.2 (95% CI: 2.0-4.9) times increase in the odds of ordering ODX in 2010-2012 after adjustment for physician gender and time in practice. In patient-level models with controls for physician and patient characteristics, seeing a medical oncologist with connections to at least two early adopting physicians is associated with a 1.6 times (95% CI: 1.1-2.2) increase in the odds of receiving ODX testing in 2010-2012.

Conclusions: We observe a positive adjusted association between connectedness to an early-adopting physician and ODX prescribing/use in both physician-level and patient-level analyses. These results suggest that provider networks may help diffuse new technologies, and that BC genomic testing is likely to be an area of shared practices between providers. Efforts to increase testing, where appropriate, may benefit from a range of peer-to-peer connection strategies.

Citation Format: Rotter J, Wilson L, Greiner M, Pollack C, Dinan M. Shared-patient physician networks and their impact on the uptake of genomic testing in early-stage breast cancer [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 P4-09-08.

The induction of core pluripotency master regulators in cancers defines poor clinical outcomes and treatment resistance

Stem cell characteristics have been associated with treatment resistance and poor prognosis across many cancer types. The ability to induce and regulate the pathways that sustain these characteristic hallmarks of lethal cancers in a novel in vitro model would greatly enhance our understanding of cancer progression and treatment resistance. In this work, we present such a model, based simply on applying standard pluripotency/embryonic stem cell media alone. Core pluripotency stem cell master regulators (OCT4, SOX2 and NANOG) along with epithelial–mesenchymal transition (EMT) markers (Snail, Slug, vimentin and N-cadherin) were induced in human prostate, breast, lung, bladder, colorectal, and renal cancer cells. RNA sequencing revealed pathways activated by pluripotency inducing culture that were shared across all cancers examined. These pathways highlight a potential core mechanism of treatment resistance. With a focus on prostate cancer, the culture-based induction of core pluripotent stem cell regulators was shown to promote survival in castrate conditions—mimicking first line treatment resistance with hormonal therapies. This acquired phenotype was shown to be mediated through the upregulation of iodothyronine deiodinase DIO2, a critical modulator of the thyroid hormone signalling pathway. Subsequent inhibition of DIO2 was shown to supress expression of prostate specific antigen, the cardinal clinical biomarker of prostate cancer progression and highlighted a novel target for clinical translation in this otherwise fatal disease. This study identifies a new and widely accessible simple preclinical model to recreate and explore underpinning pathways of lethal disease and treatment resistance.

The apoA-I mimetic peptide 4F protects apolipoprotein A-I from oxidative damage

High density lipoprotein (HDL) is prone to modification by the oxidizing and chlorinating agent hypochlorite anion (OCl^-). Oxidation of apolipoprotein (apo) A-I, the major protein in HDL, reduces ABCA-1 mediated cholesterol efflux and other protective responses to HDL. The apoA-I mimetic peptide 4F has been shown to undergo oxidation; however, the ability of the peptide to mediate cholesterol efflux remains intact. Here, we show that 4F protects apoA-I from hypochlorite-mediated oxidation. Mass spectral analysis of apoA-I shows that tyrosine residues that are prone to hypochlorite-mediated chlorination are protected in the presence of 4F. Furthermore, 4F enhances the cholesterol efflux ability of apoA-I to a greater extent than either 4F or apoA-I alone, even after hypochlorite oxidation. These observations suggest that apoA-I in lipid complexes may be protected by the presence of 4F, resulting in the preservation of its anti-inflammatory and anti-atherogenic properties. These studies also form the basis for the future studies of nanoparticles possessing both apoA-I and 4F.

History of military psychology

Military psychology is a specialist discipline within applied psychology. It entails the application of psychological science to military operations, systems and personnel. The specialty was formally founded during World War I in the UK and the USA, and it was integral to many early concepts and interventions for psychological and neuropsychological trauma. It also established a fundamental basis for the psychological assessment and selection of military personnel. During and after World War II, military psychology continued to make significant contributions to aviation psychology, cognitive testing, rehabilitation psychology and many models of psychotherapy. Military psychology now consists of several subspecialties, including clinical, research and occupational psychology, with the latter often referred to in the USA as industrial/organisational psychology. This article will provide an overview of the origins, history and current composition of military psychology in the UK, with select international illustrations also being offered.

High resolution, high signal-to-noise crystal spectrometer for measurements of line shifts in high-density plasmas

The Orion high-resolution x-ray (OHREX) spectrometer has been a successful tool for measuring the shapes of density-broadened spectral lines produced in short-pulse heated plasmas at the Orion laser facility. We have recently outfitted the instrument with a charge-couple device (CCD) camera, which greatly increased the accuracy with which we can perform line-shift measurements. Because OHREX is located on the outside of the Orion target chamber, no provisions for the shielding of electromagnetic pulses are required. With the CCD, we obtained a higher signal-to-noise ratio than we previously obtained with an image-plate detector. This allowed us to observe structure in the image produced by the diffraction from the two OHREX crystals, which was highly reproducible from shot to shot. This structure will ultimately limit the accuracy of our spectroscopic measurements.

Glucagon Receptor Signaling Regulates Energy Metabolism via Hepatic Farnesoid X Receptor and Fibroblast Growth Factor 21

Glucagon, an essential regulator of glucose and lipid metabolism, also promotes weight loss, in part through potentiation of fibroblast growth factor 21 (FGF21) secretion. However, FGF21 is only a partial mediator of metabolic actions ensuing from glucagon receptor (GCGR) activation, prompting us to search for additional pathways. Intriguingly, chronic GCGR agonism increases plasma bile acid levels. We hypothesized that GCGR agonism regulates energy metabolism, at least in part, through farnesoid X receptor (FXR). To test this hypothesis, we studied whole-body and liver-specific FXR-knockout (Fxr∆liver) mice. Chronic GCGR agonist (IUB288) administration in diet-induced obese (DIO) Gcgr, Fgf21, and Fxr whole-body or liver-specific knockout (∆liver) mice failed to reduce body weight when compared with wild-type (WT) mice. IUB288 increased energy expenditure and respiration in DIO WT mice, but not Fxr∆liver mice. GCGR agonism increased [14C]palmitate oxidation in hepatocytes isolated from WT mice in a dose-dependent manner, an effect blunted in hepatocytes from Fxr∆liver mice. Our data clearly demonstrate that control of whole-body energy expenditure by GCGR agonism requires intact FXR signaling in the liver. This heretofore-unappreciated aspect of glucagon biology has implications for the use of GCGR agonism in the therapy of metabolic disorders.

Early airway microbial metagenomic and metabolomic signatures are associated with development of severe bronchopulmonary dysplasia

The pathogenesis of bronchopulmonary dysplasia (BPD) is not well understood. We previously identified differences in the airway microbiome at birth between preterm infants who were BPD predisposed versus those who were BPD resistant. In this study, we attempted to identify mechanisms by which the airway microbiome could modify the risk for BPD. We used a software-based method to predict the metagenome of the tracheal aspirate (TA) microbiome from 16S rRNA sequencing data in preterm infants and to identify functional ortholog genes that were differentially abundant in BPD-predisposed and BPD-resistant infants. We also identified metabolites that were differentially enriched in these samples by use of untargeted mass spectrometry and mummichog to identify the metabolic pathways involved. Microbial metagenome analysis identified specific pathways that were less abundant in the functional metagenome of the microbiota of BPD-predisposed infants compared with BPD-resistant infants. The airway metabolome of BPD-predisposed infants was enriched for metabolites involved in fatty acid activation and androgen and estrogen biosynthesis compared with BPD-resistant infants. These findings suggest that in extremely preterm infants the early airway microbiome may alter the metabolome, thereby modifying the risk of BPD. The differential enrichment of sex steroid metabolic pathways supports previous studies suggesting a role for sexual dimorphism in BPD risk. This study also suggests a role for metabolomic and metagenomic profiles to serve as early biomarkers of BPD risk.

Las Competencias de Salud Global para Estudiantes de Enfermería: Percepciones de Docentes en América Latina

Objetivo: El propósito de este estudio fue describir las percepciones de docentes de enfermería de habla hispana en América Latina, sobre las competencias relacionadas a la salud global que deben mostrar los estudiantes de enfermería del pregrado. Métodos: Este estudio descriptivo fue basado en una muestra de  docentes de escuelas de enfermería miembros de la Asociación Latinoamericana de Escuelas y Facultades de Enfermería (ALADEFE) y de la Asociación de Escuelas de la Zona Centro Sur de México,  las cuales recibieron un correo electrónico con una liga para responder una encuesta electrónica por Survey Monkey©. La encuesta incluyó una lista de 30 competencias en salud global dividida en seis dimensiones. Los docentes indicaron en una escala Likert de 4 puntos la relevancia de cada competencia para la educación de enfermería en el nivel de pregrado (1 = Completamente en desacuerdo; 2 = En desacuerdo; 3 = De acuerdo; 4 = Completamente de acuerdo). Resultados: En total, 110 profesores de nueve países respondieron a la encuesta.  El promedio de cada ítem fue entre 3.0 - 4.0, esto indica que los profesores estuvieron de acuerdo en que todas las competencias son relevantes para la formación de estudiantes de enfermería a nivel de pregrado. Conclusiones: Los resultados de este estudio sugirieron que estas competencias deben ser incluidas en los currículos de enfermería a nivel de pregrado, para formar a los estudiantes en su labor como enfermeras y enfermeros en un mundo globalizado y  prepararlos para contribuir a la Cobertura y el Acceso Universal a la Salud (Salud Universal).

Hysterectomy and incidence of depressive symptoms in midlife women: the Australian Longitudinal Study on Women's Health

AIMS

There is limited longitudinal research that has looked at the longer term incidence of depressive symptoms, comparing women with a hysterectomy to women without a hysterectomy. We aimed to investigate the association between hysterectomy status and the 12-year incidence of depressive symptoms in a mid-aged cohort of Australian women, and whether these relationships were modified by use of exogenous hormones.

METHODS

We used generalised estimating equation models for binary outcome data to assess the associations of the incidence of depressive symptoms (measured by the 10-item Centre for Epidemiologic Studies Depression Scale) across five surveys over a 12-year period, in women with a hysterectomy with ovarian conservation, or a hysterectomy with bilateral oophorectomy compared with women without a hysterectomy. We further stratified women with hysterectomy by their current use of menopausal hormone therapy (MHT). Women who reported prior treatment for depression were excluded from the analysis.

RESULTS

Compared with women without a hysterectomy (n = 4002), both women with a hysterectomy with ovarian conservation (n = 884) and women with a hysterectomy and bilateral oophorectomy (n = 450) had a higher risk of depressive symptoms (relative risk (RR) 1.20; 95% confidence interval (CI) 1.06-1.36 and RR 1.44; 95% CI 1.22-1.68, respectively). There were differences in the strength of the risk for women with a hysterectomy with ovarian conservation, compared with those without, when we stratified by current MHT use. Compared with women without a hysterectomy who did not use MHT, women with a hysterectomy with ovarian conservation who were also MHT users had a higher risk of depressive symptoms (RR 1.57; 95% CI 1.31-1.88) than women with a hysterectomy with ovarian conservation but did not use MHT (RR 1.17; 95% CI 1.02-1.35). For women with a hysterectomy and bilateral oophorectomy, MHT use did not attenuate the risk. We could not rule out, however, that the higher risk seen among MHT users may be due to confounding by indication, i.e. MHT was prescribed to treat depressive symptoms, but their depressive symptoms persisted.

CONCLUSIONS

Women with a hysterectomy (with and without bilateral oophorectomy) have a higher risk of new incidence of depressive symptoms in the longer term that was not explained by lifestyle or socio-economic factors.

A REVIEW OF ANALYTICAL MODELS OF STRAY RADIATION EXPOSURES FROM PHOTON- AND PROTON-BEAM RADIOTHERAPIES

External-beam radiation therapy is safe, effective and widely used to treat cancer. With 5-year cancer survival for adults above 70%, increasingly research is focusing on quantifying and reducing treatment-related morbidity. Reducing exposures to healthy tissues is one strategy, which can be accomplished with advanced-technology radiotherapies, such as intensity-modulated photon therapy and proton therapy. Both of these modalities provide good conformation of the therapeutic dose to the tumor volume, but they also deliver stray radiation to the whole body that increases the risk of radiogenic second cancers. To minimize these risks, one needs to create and compare candidate treatment plans that explicitly take into account these risks. Currently, clinical practice does not include routine calculation of stray radiation exposure and, consequently, the assessment of corresponding risks is difficult. In this article, we review recent progress toward stray dose algorithms that are suitable for large-scale clinical use. In particular, we emphasize the current state of physics-based dose algorithms for intensity-modulated photon radiotherapy and proton therapy.

Differential Morphological and Biochemical Recovery from Chemotherapy-Induced Peripheral Neuropathy Following Paclitaxel, Ixabepilone, or Eribulin Treatment in Mouse Sciatic Nerves

The reversibility of chemotherapy-induced peripheral neuropathy (CIPN), a disabling and potentially permanent side effect of microtubule-targeting agents (MTAs), is becoming an increasingly important issue as treatment outcomes improve. The molecular mechanisms regulating the variability in time to onset, severity, and time to recovery from CIPN between the common MTAs paclitaxel and eribulin are unknown. Previously (Benbow et al. in Neurotox Res 29:299-313, 2016), we found that after 2 weeks of a maximum tolerated dose (MTD) in mice, paclitaxel treatment resulted in severe reductions in axon area density, higher frequency of myelin abnormalities, and increased numbers of Schwann cell nuclei in sciatic nerves. Biochemically, eribulin induced greater microtubule-stabilizing effects than paclitaxel. Here, we extended these comparative MTD studies to assess the recovery from these short-term effects of paclitaxel, eribulin, and a third MTA, ixabepilone, over the course of 6 months. Paclitaxel induced a persistent reduction in axon area density over the entire 6-month recovery period, unlike ixabepilone- or eribulin-treated animals. The abundance of myelin abnormalities rapidly declined after cessation of all drugs but recovered most slowly after paclitaxel treatment. Paclitaxel- and ixabepilone- but not eribulin-treated animals exhibited increased Schwann cell numbers during the recovery period. Tubulin composition and biochemistry rapidly returned from MTD-induced levels of α-tubulin, acetylated α-tubulin, and end-binding protein 1 to control levels following cessation of drug treatment. Taken together, sciatic nerve axons recovered more rapidly from morphological effects in eribulin- and ixabepilone-treated animals than in paclitaxel-treated animals and drug-induced increases in protein expression levels following paclitaxel and eribulin treatment were relatively transient.

Characterisation of a sub-20 ps temporal resolution pulse dilation photomultiplier tube

A pulse-dilation photomultiplier tube (PD-PMT) with sub-20 ps temporal resolution has been developed for use with γ-ray-sensitive gas Cherenkov detectors at the National Ignition Facility to improve the diagnosis of nuclear fusion burn history and the areal density of the remaining capsule ablator. The pulse-dilation mechanism entails the application of a time-dependent, ramp waveform to a photocathode-mesh structure, introducing a time-dependent photoelectron accelerating potential. The electric field imparts axial velocity dispersion to outgoing photoelectrons. The photoelectron pulse is dilated as it transits a drift region prior to amplification in a microchannel plate and read out with a digital oscilloscope. We report the first measurements with the prototype PD-PMT demonstrating nominal <20 ps FWHM across a 400 ps measurement window and <30 ps FWHM for an extracted charge up to 300 pC. The output peak areas are linear to within 20% over 3 orders of magnitude of input intensity. 3D particle in cell simulations, which included space charge effects, have been carried out to investigate the device temporal magnification, resolution, and linearity.

FBXW7 regulates DISC1 stability via the ubiquitin-proteosome system

Disrupted in schizophrenia 1 (DISC1) is a multi-functional scaffolding protein that has been associated with neuropsychiatric disease. The role of DISC1 is to assemble protein complexes that promote neural development and signaling, hence tight control of the concentration of cellular DISC1 in neurons is vital to brain function. Using structural and biochemical techniques, we show for we believe the first time that not only is DISC1 turnover elicited by the ubiquitin proteasome system (UPS) but that it is orchestrated by the F-Box protein, FBXW7. We present the structure of FBXW7 bound to the DISC1 phosphodegron motif and exploit this information to prove that disruption of the FBXW7-DISC1 complex results in a stabilization of DISC1. This action can counteract DISC1 deficiencies observed in neural progenitor cells derived from induced pluripotent stem cells from schizophrenia patients with a DISC1 frameshift mutation. Thus manipulation of DISC1 levels via the UPS may provide a novel method to explore DISC1 function.

Time-resolved measurements of fast electron recirculation for relativistically intense femtosecond scale laser-plasma interactions

A key issue in realising the development of a number of applications of high-intensity lasers is the dynamics of the fast electrons produced and how to diagnose them. We report on measurements of fast electron transport in aluminium targets in the ultra-intense, short-pulse (<50 fs) regime using a high resolution temporally and spatially resolved optical probe. The measurements show a rapidly (≈0.5c) expanding region of Ohmic heating at the rear of the target, driven by lateral transport of the fast electron population inside the target. Simulations demonstrate that a broad angular distribution of fast electrons on the order of 60° is required, in conjunction with extensive recirculation of the electron population, in order to drive such lateral transport. These results provide fundamental new insight into fast electron dynamics driven by ultra-short laser pulses, which is an important regime for the development of laser-based radiation and particle sources.

Comprehensive profiling of prostaglandins in human ovarian follicular fluid using mass spectrometry

Prostaglandins are formed by enzymatic and non-enzymatic mechanisms. They have been detected in human ovarian follicular fluid (HFF), a medium rich in growth factors and nutrients important for oocyte growth and fertility. However, the comprehensive identification of HFF prostaglandins has not been addressed. Here we use hybrid triple quadrupole time-of-flight and triple quadrupole mass spectrometers to comprehensively analyze prostaglandins in HFF. We identified PGE1, PGE2, PGF2α, and other prostaglandins synthesized via prostaglandin-endoperoxide synthase (i.e. Cox) cascades. We also identified specific PGF2α isomers (F2-isoprostanes) and PGF3α analogs whose structures are inconsistent with Cox-dependent formation. A prospective cohort pilot study of infertility patient subtypes revealed two potential associations. F2-isoprostanes are decreased in the diminished ovarian reserve subtype and elevated PGF2α may be associated with decreased live birth. Other than PGF2α, only body mass index >25kg/m2 correlated with poor in vitro fertilization outcome. Our studies suggest that HFF contains prostaglandins formed from at least two mechanisms, which may correlate with distinct clinical parameters.