What can entropy metrics tell us about the characteristics of ocular fixation trajectories?

In this study, we provide a detailed analysis of entropy measures calculated for fixation eye movement trajectories from the three different datasets. We employed six key metrics (Fuzzy, Increment, Sample, Gridded Distribution, Phase, and Spectral Entropies). We calculate these six metrics on three sets of fixations: (1) fixations from the GazeCom dataset, (2) fixations from what we refer to as the "Lund" dataset, and (3) fixations from our own research laboratory ("OK Lab" dataset). For each entropy measure, for each dataset, we closely examined the 36 fixations with the highest entropy and the 36 fixations with the lowest entropy. From this, it was clear that the nature of the information from our entropy metrics depended on which dataset was evaluated. These entropy metrics found various types of misclassified fixations in the GazeCom dataset. Two entropy metrics also detected fixation with substantial linear drift. For the Lund dataset, the only finding was that low spectral entropy was associated with what we call "bumpy" fixations. These are fixations with low-frequency oscillations. For the OK Lab dataset, three entropies found fixations with high-frequency noise which probably represent ocular microtremor. In this dataset, one entropy found fixations with linear drift. The between-dataset results are discussed in terms of the number of fixations in each dataset, the different eye movement stimuli employed, and the method of eye movement classification.

Hydrogen Bonding Compensation on the Convex Solvent-Exposed Helical Face of IA3, an Intrinsically Disordered Protein

Saccharomyces cerevisiae IA₃ is a 68 amino acid peptide inhibitor of yeast proteinase A (YPRA) characterized as a random coil when in solution, folding into an N-terminal amphipathic alpha helix for residues 2-32 when bound to YPRA, with residues 33-68 unresolved in the crystal complex. Circular dichroism (CD) spectroscopy results show that amino acid substitutions that remove hydrogen-bonding interactions observed within the hydrophilic face of the N-terminal domain (NTD) of IA₃-YPRA crystal complex reduce the 2,2,2-trifluoroethanol (TFE)-induced helical transition in solution. Although nearly all substitutions decreased TFE-induced helicity compared to wild-type (WT), each construct did retain helical character in the presence of 30% (v/v) TFE and retained disorder in the absence of TFE. The NTDs of 8 different Saccharomyces species have nearly identical amino acid sequences, indicating that the NTD of IA₃ may be highly evolved to adopt a helical fold when bound to YPRA and in the presence of TFE but remain unstructured in solution. Only one natural amino acid substitution explored within the solvent-exposed face of the NTD of IA₃ induced TFE-helicity greater than the WT sequence. However, chemical modification of a cysteine by a nitroxide spin label that contains an acetamide side chain did enhance TFE-induced helicity. This finding suggests that non-natural amino acids that can increase hydrogen bonding or alter hydration through side-chain interactions may be important to consider when rationally designing intrinsically disordered proteins (IDPs) with varied biotechnological applications.

GazeBaseVR, a large-scale, longitudinal, binocular eye-tracking dataset collected in virtual reality

We present GazeBaseVR, a large-scale, longitudinal, binocular eye-tracking (ET) dataset collected at 250 Hz with an ET-enabled virtual-reality (VR) headset. GazeBaseVR comprises 5,020 binocular recordings from a diverse population of 407 college-aged participants. Participants were recorded up to six times each over a 26-month period, each time performing a series of five different ET tasks: (1) a vergence task, (2) a horizontal smooth pursuit task, (3) a video-viewing task, (4) a self-paced reading task, and (5) a random oblique saccade task. Many of these participants have also been recorded for two previously published datasets with different ET devices, and 11 participants were recorded before and after COVID-19 infection and recovery. GazeBaseVR is suitable for a wide range of research on ET data in VR devices, especially eye movement biometrics due to its large population and longitudinal nature. In addition to ET data, additional participant details are provided to enable further research on topics such as fairness.

Factors affecting inter-rater agreement in human classification of eye movements: a comparison of three datasets

Manual classification of eye-movements is used in research and as a basis for comparison with automatic algorithms in the development phase. However, human classification will not be useful if it is unreliable and unrepeatable. Therefore, it is important to know what factors might influence and enhance the accuracy and reliability of human classification of eye-movements. In this report we compare three datasets of human manual classification, two from earlier datasets and one, our own dataset, which we present here for the first time. For inter-rater reliability, we assess both the event-level F1-score and sample-level Cohen's κ, across groups of raters. The report points to several possible influences on human classification reliability: eye-tracker quality, use of head restraint, characteristics of the recorded subjects, the availability of detailed scoring rules, and the characteristics and training of the raters.

Systematic scoping review of occupational health injuries and illnesses among Indigenous workers

Indigenous populations in the USA, Australia, New Zealand (NZ) and Canada total more than 13 million, but continue to be marginalised in their respective regions. The goal of this comprehensive review of all studies evaluating adverse occupational health outcomes among Indigenous populations in these countries was to identify gaps in the literature and future research directions. A systematic scoping review of research published between 1970 and 2020 was undertaken using the methodological framework initially proposed by Arksey and O'Malley. Country, Indigenous participants, study type, exposure, adverse health outcome, occupation and industry were identified for each paper. Of the 1272 research papers identified, only 51 articles met the inclusion criteria of this scoping review. Almost half of the studies (n=24, 47.1%) were published after 2010. Only 13 (25.5%) studies specifically focused on Indigenous persons at the time of the study design, and less than half of the studies (47.1%) included more than 100 Indigenous participants. Most studies used the following general terms without mention of specific indigenous groups: Indigenous (Australia), Māori (NZ), Aboriginal (Canada) and American Indian or Alaskan Native (USA). Only one study acknowledged asking respondents their preferred terminology. Over the past 50 years, there has been a paucity of research directly or indirectly evaluating occupational health outcomes of Indigenous populations in these four countries. There is a need for better sampling strategies and inclusion of demographic questions that capture Indigenous status in surveys, workers' compensation data and other commonly used data sources to develop adequate baseline data for targeted future interventions.

Multimodality During Fixation - Part II: Evidence for Multimodality in Spatial Precision-Related Distributions and Impact on Precision Estimates

This paper is a follow-on to our earlier paper (7), which focused on the multimodality of angular offsets. This paper applies the same analysis to the measurement of spatial precision. Following the literature, we refer these measurements as estimates of device precision, but, in fact, subject characteristics clearly affect the measurements. One typical measure of the spatial precision of an eye-tracking device is the standard deviation (SD) of the position signals (horizontal and vertical) during a fixation. The SD is a highly interpretable measure of spread if the underlying error distribution is unimodal and normal. However, in the context of an underlying multimodal distribution, the SD is less interpretable. We will present evidence that the majority of such distributions are multimodal (68-70% strongly multimodal). Only 21-23% of position distributions were unimodal. We present an alternative method for measuring precision that is appropriate for both unimodal and multimodal distributions. This alternative method produces precision estimates that are substantially smaller than classic measures. We present illustrations of both unimodality and multimodality with either drift or a microsaccade present during fixation. At present, these observations apply only to the EyeLink 1000, and the subjects evaluated herein.

Advances in microfluidic extracellular vesicle analysis for cancer diagnostics

Extracellular vesicles (EVs) secreted by cells into the bloodstream and other bodily fluids, including exosomes, have been demonstrated to be a class of significant messengers that mediate intercellular communications. Tumor-derived extracellular vesicles are enriched in a selective set of biomolecules from original cells, including proteins, nucleic acids, and lipids, and thus offer a new perspective of liquid biopsy for cancer diagnosis and therapeutic monitoring. Owing to the heterogeneity of their biogenesis, physical properties, and molecular constituents, isolation and molecular characterization of EVs remain highly challenging. Microfluidics provides a disruptive platform for EV isolation and analysis owing to its inherent advantages to promote the development of new molecular and cellular sensing systems with improved sensitivity, specificity, spatial and temporal resolution, and throughput. This review summarizes the state-of-the-art advances in the development of microfluidic principles and devices for EV isolation and biophysical or biochemical characterization, in comparison to the conventional counterparts. We will also survey the progress in adapting the new microfluidic techniques to assess the emerging EV-associated biomarkers, mostly focused on proteins and nucleic acids, for clinical diagnosis and prognosis of cancer. Lastly, we will discuss the current challenges in the field of EV research and our outlook on future development of enabling microfluidic platforms for EV-based liquid biopsy.

Angular Offset Distributions During Fixation Are, More Often Than Not, Multimodal

Typically, the position error of an eye-tracking device is measured as the distance of the eye-position from the target position in two-dimensional space (angular offset). Accuracy is the mean angular offset. The mean is a highly interpretable measure of central tendency if the underlying error distribution is unimodal and normal. However, in the context of an underlying multimodal distribution, the mean is less interpretable. We will present evidence that the majority of such distributions are multimodal. Only 14.7% of fixation angular offset distributions were unimodal, and of these, only 11.5% were normally distributed. (Of the entire dataset, 1.7% were unimodal and normal.) This multimodality is true even if there is only a single, continuous tracking fixation segment per trial. We present several approaches to measure accuracy in the face of multimodality. We also address the role of fixation drift in partially explaining multimodality.

Media Reports as a Tool for Timely Monitoring of COVID-19-Related Deaths Among First Responders-United States, April 2020

We aimed to describe coronavirus disease 2019 (COVID-19) deaths among first responders early in the COVID-19 pandemic. We used media reports to gather timely information about COVID-19-related deaths among first responders during March 30-April 30, 2020, and evaluated the sensitivity of media scanning compared with traditional surveillance. We abstracted information about demographic characteristics, occupation, underlying conditions, and exposure source. Twelve of 19 US public health jurisdictions with data on reported deaths provided verification, and 7 jurisdictions reported whether additional deaths had occurred; we calculated the sensitivity of media scanning among these 7 jurisdictions. We identified 97 COVID-19-related first-responder deaths during the study period through media and jurisdiction reports. Participating jurisdictions reported 5 deaths not reported by the media. Sixty-six decedents worked in law enforcement, and 31 decedents worked in fire/emergency medical services. Media reports rarely noted underlying conditions. The media scan sensitivity was 88% (95% CI, 73%-96%) in the subset of 7 jurisdictions. Media reports demonstrated high sensitivity in documenting COVID-19-related deaths among first responders; however, information on risk factors was scarce. Routine collection of data on industry and occupation could improve understanding of COVID-19 morbidity and mortality among all workers.

Levels of Ethylene Oxide Biomarker in an Exposed Residential Community

The purpose of this study was to examine whether there is a difference in ethylene oxide (EtO) biomarker levels based on residential proximity to facilities emitting EtO, a carcinogen. We recruited residents living near two EtO-emitting facilities and administered a questionnaire on items such as address and length of residency, smoking habits, occupational exposures to EtO, and demographics. We also collected venous blood samples to measure an EtO biomarker, hemoglobin adduct N-2-hydroxyethyl-valine (HbEO), and cotinine, a metabolite of nicotine. Questionnaires and blood samples were collected from 93 participants. The overall geometric HbEO adduct level was 35.0 pmol/gmHb and for nonsmokers it was 29.7 pmol/gmHb. Mean HbEO adduct levels were not significantly associated with sex, age, race, BMI, or education level. HbEO adduct levels for nonsmoking participants who lived in a neighborhood approximately 0.8 km from one of the facilities were significantly higher compared to persons living farther away (p < 0.001). These results suggest that facilities that emit EtO may put nearby communities at risk of cancer and other associated health outcomes.

Why Temporal Persistence of Biometric Features, as Assessed by the Intraclass Correlation Coefficient, Is So Valuable for Classification Performance

It is generally accepted that relatively more permanent (i.e., more temporally persistent) traits are more valuable for biometric performance than less permanent traits. Although this finding is intuitive, there is no current work identifying exactly where in the biometric analysis temporal persistence makes a difference. In this paper, we answer this question. In a recent report, we introduced the intraclass correlation coefficient (ICC) as an index of temporal persistence for such features. Here, we present a novel approach using synthetic features to study which aspects of a biometric identification study are influenced by the temporal persistence of features. What we show is that using more temporally persistent features produces effects on the similarity score distributions that explain why this quality is so key to biometric performance. The results identified with the synthetic data are largely reinforced by an analysis of two datasets, one based on eye-movements and one based on gait. There was one difference between the synthetic and real data, related to the intercorrelation of features in real data. Removing these intercorrelations for real datasets with a decorrelation step produced results which were very similar to that obtained with synthetic features.

A 5-Year Retrospective Analysis of Legal Intervention Injuries and Mortality in Illinois

There has been a public outcry for the accountability of law enforcement agents who kill and injure citizens. Epidemiological surveillance can underscore the magnitude of morbidity and mortality of citizens at the hands of law enforcement. We used hospital outpatient and inpatient databases to conduct a retrospective analysis of legal interventions in Illinois between 2010 and 2015. We calculated injury and mortality rates based on demographics, spatial distribution, and cause of injury. During the study period, 8,384 patients were treated for injuries caused during contact with law enforcement personnel. Most were male, the mean age was 32.7, and those injured were disproportionately black. Nearly all patients were treated as outpatients, and those who were admitted to the hospital had a mean of length of stay of 6 days. Most patients were discharged home or to an acute or long-term care facility (83.7%). It is unclear if those discharged home or to a different medical facility were arrested, accidentally injured, injured when no crime was committed, or injured when a crime was committed. Surveillance of law enforcement-related injuries and deaths should be implemented, and injuries caused during legal interventions should be recognized as a public health issue rather than a criminal justice issue.

Abstract P5-04-26: Identification of preclinical mechanisms driving acquired resistance to endocrine therapy in estrogen-receptor positive (ER+) breast cancer cells

Estrogen Receptor positive (ER+) breast cancer accounts for the majority of breast cancer cases and standard of care for these tumors is treatment with endocrine therapy, including the blockade of estrogen production (i.e. aromatase inhibitors; AIs) as well as the use of antagonists of ER function, i.e. selective estrogen receptor modulators (SERMs, i.e. tamoxifen) and selective estrogen receptor degraders (SERDs, i.e. fulvestrant). Despite the initial dependency of ER+ breast tumors on estrogen and ER for their survival and proliferation, treatment in the metastatic setting invariably leads to therapeutic resistance. While mechanisms of resistance to AIs include mutations in the estrogen receptor gene ESR1, less is known about mechanisms of resistance to SERMs and SERDs, thus it is essential to further investigate the latter, in order to successfully treat relapsed patients. To pre-clinically model cell-autonomous acquired resistance to these agents, we used T47D, an ER+ and p53- estrogen-responsive cell line treated with increasing concentrations of the SERM/SERD hybrid (SSH) ER-targeting agent GDC-0810 over the period of several months during which individual clones with acquired resistance to GDC-0810 were selected. GDC-0810-resistant clones were cross-resistant to other endocrine agents, including SERMs (tamoxifen) and SERDs (fulvestrant), consistent with general loss of dependency on ER. Surprisingly, the cells also lost sensitivity to palbociclib, the latter likely linked to their loss of one copy of the retinoblastoma (Rb) tumor suppressor gene. Comprehensive genetic and phenotypic characterization of the resistant clones relative to the parental cells revealed multiple mutations and deletions in DNA repair and cell cycle genes, and associated defects in DNA repair and cell cycle checkpoints. Cell cycle, proteomic, and mRNA expression analysis of parental versus resistant clones at baseline and upon DNA damage, identified a distinct cell cycle profile in the GDC-0810-resistant clones, characterized by accumulation of cells in the mitotic phase. A broad chemical screen identified pharmacologic inhibitors of cell cycle regulators and chemotherapeutic drug classes that preferentially target the ER-independent, GDC-0810 resistant clones compared to the parental cells. Our work provides novel insights into mechanisms and biomarkers of acquired resistant to estrogen therapies in ER+ breast cancer and reveals the acquisition of actionable dependencies that may potentially be exploited in resistant tumors. Furthermore, our studies provide rationale for testing specific chemotherapy regimens upon endocrine resistance accompanied by cell cycle and DNA repair checkpoint dysfunction in ER+ breast cancer.

Citation Format: Ong C, Daemen A, Merrick K, O'Brien T, Friedman L, Hatzivassiliou G. Identification of preclinical mechanisms driving acquired resistance to endocrine therapy in estrogen-receptor positive (ER+) breast cancer cells [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 P5-04-26.

Meta-analyses of cavum septum pellucidum in mood disorders in comparison with healthy controls or schizophrenia

The cavum septum pellucidum (CSP) is a neurodevelopmental abnormality significantly more prevalent in subjects with schizophrenia (SCZ) than in healthy controls (HC). Using meta-analyses, we tested the hypotheses whether CSP would be more frequent in subjects with mood disorders when compared with HC or SCZ. We performed a search in MEDLINE and EMBASE followed by 10 meta-analyses of magnetic resonance imaging studies which examined the association of CSP in bipolar disorders (BD), major depressive disorder (MDD) or mood disorders (MD; considering MDD and BD combined) with either HC or SCZ. Nine studies were included, comprising 692 cases (363 with BD, 182 with MDD and 147 with MD), 463 with SCZ and 630 HC. CSP of any size was significantly associated with BD (OR = 2.07, 95% CI: 1.48-2.90) when compared with HC. Large CSP showed a trend to be associated with BD when compared with HC, but the association was not statistically significant (OR = 1.92, 95% CI 0.64-5.78). Large CSP was significantly associated with subjects with SCZ when compared with subjects with MD (OR = 0.57, 95% CI: 0.36-0.92). There was no association between CSP and MDD in comparison to HC or subjects with SCZ. Cortical structures are known to be altered in mood disorders. The present metanalysis found that certain midline brain abnormalities, such as CSP, are also associated with BD.

Association between Type of Residence and Clinical Signs of Neglect in Older Adults

BACKGROUND

Studies have demonstrated that measures of lower quality of care and associated adverse health effects are more prevalent in for-profit nursing homes compared to not-for-profit facilities. However, these studies omit persons who receive care in the community setting, and exclusively focus on isolated clinical signs that may obscure the true effect size, since these clinical signs rarely occur in isolation.

OBJECTIVE

In this study, we use the Clinical Signs of Neglect Scale (CSNS), which is an aggregate measure of clinical signs of neglect and substandard care, to evaluate the association of residence type on health outcomes among individuals living in both private community residences and for-profit and not-for-profit long-term care facilities.

METHODS

In a multicenter, retrospective data analysis of 1,149 patients identified from an inpatient hospital registry, we assessed the relationship between residence type (community dwelling, not-for-profit, and for-profit facilities) and clinical signs of neglect. Adjusted parameter estimates and 95% CIs were estimated with linear regression in 3 models using different reference groups.

RESULTS

The most serious clinical signs were consistently more prevalent among residents of for-profit facilities, as were measures of poor institutional quality. Relative to low-functioning community-dwelling patients, the mean difference in CSNS scores was higher among patients residing in not-for-profit facilities by 1.99 (p = 0.012) and 3.55 (p ≤ 0.001) among patients in for-profit facilities. In a separate model, the mean difference in CSNS scores among patients living in for-profit facilities compared to not-for-profit facilities was 1.90 (p = 0.035).

CONCLUSIONS

Using an aggregate measure, our findings support prior studies demonstrating an association between residence type and adverse health outcomes for disabled elderly.

Sex ratio in dementia with Lewy bodies balanced between Alzheimer's disease and Parkinson's disease dementia: a cross-sectional study

Background

Gender distribution varies across neurodegenerative disorders, with, traditionally, a higher female frequency reported in Alzheimer’s disease (AD) and a higher male frequency in Parkinson’s disease (PD). Conflicting results on gender distribution are reported concerning dementia with Lewy bodies (DLB), usually considered as an intermediate disease between AD and PD. The aim of the present study was to investigate gender differences in DLB in French specialized memory settings using data from the French national database spanning from 2010 to 2015 and to compare sex ratio in DLB with that in AD, Parkinson’s disease dementia (PDD), and PD. Our hypothesis was that there is a balanced sex ratio in DLB, different from that found in AD and PD.

Methods

We conducted a repeated cross-sectional study. The study population comprised individuals with a DLB, AD, PDD, or PD diagnosis according to the International Classification of Diseases, Tenth Revision, in the French National Alzheimer Database between 2010 and 2015. Sex ratio and demographic data were compared using multinomial logistic regression and a Bayesian statistical model.

Results

From 2010 to 2015 in French specialized memory settings, sex ratios (female percent/male percent) were found as follows: 1.21 (54.7%/45.3%) for DLB (n = 10,309), 2.34 (70.1%/29.9%) for AD (n = 135,664), 0.76 (43.1%/56.9%) for PD (n = 8744), and 0.83 (45.4%/54.6%) for PDD (n = 3198). Significant differences were found between each group, but not between PDD and PD, which had a similar sex ratio.

Conclusions

This large-sample prevalence study confirms the balanced gender distribution in the DLB population compared with AD and PD-PDD. Gender distribution and general demographic characteristics differed between DLB and PDD. This is consistent with the hypothesis that DLB is a distinct disease with characteristics intermediate between AD and PD, as well as with the hypothesis that DLB could have at least partially distinct neuropathological correlates.

Postpartum hemoptysis as presenting sign of longstanding vasculitis

We present the case of a 26-year-old postpartum patient who presented with an episode of desaturation and hemoptysis on postpartum day three after an uncomplicated spontaneous vaginal delivery. The patient came to our attention in the postpartum area after she experienced massive hemoptysis and we were called by the obstetric team. The patient was subsequently intubated, mechanically ventilated, and underwent bronchoscopy, demonstrating diffuse alveolar hemorrhage. She was brought to the intensive care unit, placed on high-dose steroids and plasmapheresis was initiated. Her intensive care unit course was complicated by acute respiratory distress syndrome, acute kidney injury and a pulmonary embolism, but she recovered well and was discharged on postpartum day 23. This report describes a rare case of medium vessel vasculitis diagnosed in the peripartum period, and describes the diagnostic dilemmas underlying making a rare diagnosis, and the difficulties initiating appropriate therapy in a postpartum patient.

High exposure mining occupations are associated with obstructive lung disease, National Health Interview Survey (NHIS), 2006-2015

BACKGROUND

The association between mining occupation categories and obstructive lung disease (OLD) has not been well explored in the United States.

METHODS

National Health Interview Survey (NHIS) data from 2006 to 2015 was used to determine the relationship between mining occupations and diagnosis of chronic bronchitis, emphysema, chronic obstructive pulmonary disease (COPD), and asthma. We classified occupations into low, moderate, high, and very high dust exposure groups. Extraction workers were categorized as very high dust exposure.

RESULTS

We found 4.5% of miners had chronic bronchitis, 3.3% had emphysema, 6.2% had COPD, and 9.9% had asthma. In fully adjusted models, extraction workers had significantly increased odds of having chronic bronchitis (OR = 2.18 [95%CI: 1.02, 4.64]), emphysema (OR = 7.85 [95%CI: 1.70, 36.27]), and COPD (OR = 2.56 [95%CI: 1.29, 5.12]) compared to lower exposure occupations.

CONCLUSIONS

Occupation is an important predictor of OLD in the mining industry.

Study of an Extensive Set of Eye Movement Features: Extraction Methods and Statistical Analysis

This work presents a study of an extensive set of 101 categories of eye movement features from three types of eye movement events: fixations, saccades, and post-saccadic oscillations. We present a unified framework of methods for the extraction of features that describe the temporal, positional and dynamic characteristics of eye movements. We perform statistical analysis of feature values by employing eye movement data from a normative population of 298 subjects, recorded during a text reading task. We present overall measures for the central tendency and variability of feature values, and we quantify the test-retest reliability of features using either the Intraclass Correlation Coefficient (for normally distributed and normalized features) or Kendall’s coefficient of concordance (for non-normally distributed features). Finally, for the case of normally distributed and normalized features we additionally perform factor analysis and provide interpretations of the resulting factors. The presented methods and analysis can provide a valuable tool for researchers in various fields that explore eye movements, such as in behavioral studies, attention and cognition research, medical research, biometric recognition, and humancomputer interaction.

Workers' compensation and the working poor: Occupational health experience among low wage workers in federally qualified health centers

BACKGROUND

The working poor are at highest risk of work-related injuries and have limited access to occupational health care.

OBJECTIVES

To explore community health centers (CHCs) as a venue for accessing at risk workers; and to examine the experience, knowledge, and perceptions of workers' compensation (WC) among the working poor.

METHODS

Key informant interviews were conducted among patients in waiting rooms of rural and urban CHCs.

RESULT

Fifty-one interviews of minority workers across sectors identified 23 prior work-related injuries and mixed experiences with the WC system. Barriers to reporting and ways to overcome these barriers were elucidated.

CONCLUSIONS

Patients in CHCs work in jobs that put them at risk for work-related injuries. CHCs are a good site for accessing at-risk workers. Improving occupational healthcare and appropriate billing of WC insurance should be explored, as should best practices for employers to communicate WC laws to low wage workers.

Abstract P4-04-07: Characterization of the effects of estrogen receptor alpha Y537S and D538G mutations on receptor function and pharmacology

The frontline therapy for estrogen receptor alpha (ERα) positive Breast Cancer (ER+BC) involves various forms of endocrine therapy, consisting of either Selective Estrogen Receptor Modulators (SERMs) or aromatase inhibitors. An emerging mechanism of ER+BC resistance to endocrine therapy, and consequently disease relapse, has been associated with a set of “hotspot” mutations in and near to helix-12 of the ERα ligand binding domain. Selective Estrogen Receptor Degraders/Down-regulators (SERDs), such as GDC-0810, AZD9496 and GDC-0927, represent a current major pharmacological strategy being applied to develop treatments for such resistant ER+BC. Here, we compare 2 of the most frequent ERα hotspot mutations (Y537S and D538G), with ERα wildtype (WT) and the ability of a set of ERα ligands (including GDC-0810, AZD9496 and GDC-0927) to bind, antagonize and degrade ERα. The concentration of each drug required to bind, antagonize or degrade ERα Y537S or ERα D538G was typically higher than that required for ERα WT. Importantly, ERα Y537S is resistant to estradiol stimulated protein degradation and 4-hydroxy-tamoxifen (a major active metabolite of tamoxifen) stabilizes ERα Y537S protein. This represents a potential mechanism of resistance of ERα Y537S ER+BC to Tamoxifen therapy.

Citation Format: Blake RA, Hartman SJ, Kleinheinz TL, White J, Daly S, Goodwin R, Zhou W, Liang J, Wang X, O'Rourke M, Metcalfe C, Friedman L. Characterization of the effects of estrogen receptor alpha Y537S and D538G mutations on receptor function and pharmacology [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 P4-04-07.

Method to assess the temporal persistence of potential biometric features: Application to oculomotor, gait, face and brain structure databases

We introduce the intraclass correlation coefficient (ICC) to the biometric community as an index of the temporal persistence, or stability, of a single biometric feature. It requires, as input, a feature on an interval or ratio scale, and which is reasonably normally distributed, and it can only be calculated if each subject is tested on 2 or more occasions. For a biometric system, with multiple features available for selection, the ICC can be used to measure the relative stability of each feature. We show, for 14 distinct data sets (1 synthetic, 8 eye-movement-related, 2 gait-related, and 2 face-recognition-related, and one brain-structure-related), that selecting the most stable features, based on the ICC, resulted in the best biometric performance generally. Analyses based on using only the most stable features produced superior Rank-1-Identification Rate (Rank-1-IR) performance in 12 of 14 databases (p = 0.0065, one-tailed), when compared to other sets of features, including the set of all features. For Equal Error Rate (EER), using a subset of only high-ICC features also produced superior performance in 12 of 14 databases (p = 0. 0065, one-tailed). In general, then, for our databases, prescreening potential biometric features, and choosing only highly reliable features yields better performance than choosing lower ICC features or than choosing all features combined. We also determined that, as the ICC of a group of features increases, the median of the genuine similarity score distribution increases and the spread of this distribution decreases. There was no statistically significant similar relationships for the impostor distributions. We believe that the ICC will find many uses in biometric research. In case of the eye movement-driven biometrics, the use of reliable features, as measured by ICC, allowed to us achieve the authentication performance with EER = 2.01%, which was not possible before.

Abstract P4-06-05: Treatment of ESR1 mutant and PIK3CA mutant patient-derived breast cancer xenograft models reveals differential anti-tumor responses to estrogen receptor degraders and PI3K inhibitors in vivo

The phosphoinositide 3-kinase (PI3K) pathway is a key driver of hormone receptor (HR)–positive breast cancer growth and survival. It is estimated that 40-45% of HR+ breast cancers harbor oncogenic mutations in the PIK3CA gene, which encodes the p110α isoform of PI3K. Taselisib (GDC-0032) is a mutant-selective PI3K inhibitor that demonstrates enhanced potency in PIK3CA mutant breast cancer cells and is being developed as a treatment for metastatic breast cancer that targets PIK3CA-mutant, HR-positive, HER2-negative patients. Activating mutations in the ESR1 gene were recently described in metastatic breast cancer. These mutations confer hormone independent growth and may be associated with resistance to aromatase inhibitors. Drugs that selectively bind and antagonize the Estrogen Receptor alpha (ERα) protein and target it for degradation, such as fulvestrant, are referred to as selective estrogen receptor degraders (SERDs). Preclinical activity of the orally bioavailable SERD, GDC-0810, has not been well characterized in ESR1 mutant PDX models. Therefore, our aim was to evaluate the efficacy and pharmacodynamic responses to agents that target ERα and PI3K as monotherapies and in combination, in ESR1 and PIK3CA mutant HR+ breast cancer patient-derived xenograft (PDX) models. We hypothesized that mutational status of ESR1 and PIK3CA may predict the responsiveness of HR+ PDX models to SERDs and PI3K inhibitors in vivo. Characterization of seven PDX models included authentication of hormone receptor status by immunohistochemistry (IHC) and determination of ESR1 and PIK3CA genotype and allele frequency by exome sequencing. For a subset of models that utilize estrogen for growth, mice were supplemented with 17β-estradiol, and cells or tumor fragments were implanted into the fat pad of intact female NOD-SCID or NOD-SCID-IL2Rgamma null mice and treated with fulvestrant, GDC-0810, or taselisib. Both fulvestrant and GDC-0810 were efficacious in ESR1 wild type (WT) and mutant PDX models but to variable degrees ranging from tumor stasis to growth delay, with GDC-0810 resulting in superior single agent activity at relevant clinical exposure in the WHIM20 and WHIM43 ESR1 mutant models. PIK3CA mutations (E542K, E545K, M1004V, and H1047R) were confirmed in six PDX models and PI3K pathway activation verified by strong pS6RP IHC staining. Taselisib induced tumor growth inhibition and tumor regressions in models harboring PIK3CA mutations, and models with no detectable expression of WT p110α were the most sensitive. In the WHIM43 (ESR1 D538G, PIK3CA M1004V), HCI-011 (ESR1 WT, PIK3CA E545K) and HCI-013 (ESR1 Y537S, PIK3CA H1047R) PDX models, combining fulvestrant and taselisib treatment further enhanced tumor growth inhibition with respect to either treatment alone. Our studies demonstrate the diverse anti-tumor responses of HR+ PDX models to SERDs and the PI3K inhibitor taselisib in the context of clinically relevant ESR1 and PIK3CA mutations. Pharmacological and genomic characterization of additional PDX models may aid in strengthening associations between genotype, drug sensitivity and predictive biomarkers of response.

Citation Format: Young A, Crocker L, Cheng E, Lacap J, Hamilton P, Oeh J, Ingalla E, Arrazate A, Hager J, Nannini M, Friedman L, Daemen A, Giltnane J, Sampath D. Treatment of ESR1 mutant and PIK3CA mutant patient-derived breast cancer xenograft models reveals differential anti-tumor responses to estrogen receptor degraders and PI3K inhibitors in vivo [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-06-05.

Abstract P5-03-05: Development of a panel of serum-based protein biomarkers for the non-invasive detection of breast cancer in BI-RADS category 4 patients

Background: Current breast cancer screening guidelines call for annual mammography for asymptomatic women age 45 to 54 and once every two years for women age 55 and older. Women with suspicious screening mammograms are recommended for a diagnostic mammogram and may also undergo MRI or ultrasound. Ultimately, suspicious findings unresolved by imaging typically result in the recommendation of a breast biopsy. Approximately 10% of suspicious diagnostic mammograms are recommended for breast biopsies and 67% to 95% of these biopsies yield negative results. With the goal of reducing the number of patients with benign pathology undergoing invasive biopsies, we conducted a screen for serum protein biomarkers and identified a novel panel for the non-invasive detection of breast cancer.

Methods: Serum samples were collected at two sites from women with suspicious diagnostic mammogram findings (primarily BI-RADS category 4) undergoing biopsy for the evaluation of a potential malignancy. Serum samples from 100-patients (50 benign pathology and 50 malignant pathology) were evaluated on the SOMAscan Assay 1.3k, which measures levels of 1,310 different protein analytes. Statistical screening methodologies, such as individual t-tests with control for false discovery, were used to identify markers with the potential to distinguish benign from malignant pathology. The candidate markers were further studied and combined using generalized linear modeling to develop three potential diagnostic models. K-fold cross validation was used to guard against over fitting of the models.

Results: A 15-marker model resulted in an AUC of 0.92 with a sensitivity of 90% and specificity of 76%. Two 6-marker models (with 4 markers in common) each resulted in AUC of 0.85, yielding a sensitivity of 90% with a specificity of 56% or 64%.

Conclusions: This study reveals a novel panel of serum protein biomarkers that may allow for the non-invasive and sensitive detection of breast cancer in BI-RADS category 4 patients. A multicenter study is underway to further refine and validate this panel in a larger set of prospectively collected patient samples.

Citation Format: Chapman KB, Copeland K, Kidd J, Qiu L, Sheibani N, Tam O, Friedman L, Korn R, Fiorica J, Lourenco A, Suthers S, Hesterberg L. Development of a panel of serum-based protein biomarkers for the non-invasive detection of breast cancer in BI-RADS category 4 patients [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-03-05.

Abstract P6-03-01: A combination of dual inhibition in HER2-network by T-DM1 and GDC-0980 provides maximal antitumor efficacy in preclinical model of HER2+ breast cancer

Background: PIK3CA mutation is associated with a lower pCR rate in primary HER2+ breast cancer (BC) treated with trastuzumab and lapatinib in addition to chemotherapy (from five clinical trials, PMID: 27177864). The BOLERO-1 study showed that the efficacy of a combination of mTOR inhibitor (everolimus) plus trastuzumab (T) and paclitaxel was not very efficacious with HER2+ advanced BC patients except for HER2+/ER- BC patients (PMID: 26092818). In the same line, BOLERO 3 trial data showed the same combination (T + everolimus + vinorelbine) is also not efficacious in T-resistant, HER2+ advanced breast cancer women (median PFS 7 months with everolimus and 5.78 months with placebo, HR: 0.78) (PMID: 24742739). T-DM1 does not have typical adverse events of chemotherapy. Therefore, there has been interest in combining it with other targeted agent. Here we tested the efficacy of a combination of T-DM1 plus GDC-0980 (a dual PI3K/mTOR inhibitor) in HER2+/T-resistant BC cell lines in vitro and in vivo. Methodology: Here we have studied the in vitro and in vivo effects of GDC-0980 along with T-DM1 in HER2+/T-sensitive (BT474), HER2+/T-resistant (BT474HerR), and HER2+/PIK3CA (HCC1954, MDA-MB453) mutated models. We assessed in vitro anti-proliferative, pro-apoptotic and activation status of the PI3K-AKT-mTOR signaling pathway following the combination of GDC-0980 plus T-DM1 in HER2+ BC cell lines. We next evaluated the impact of GDC-0980 plus T-DM1 on tumor growth and angiogenesis using xenograft models. Results: 1) GDC-0980 inhibited downstream activation of the PI3K-mTOR signaling pathway effectors, p-AKT (Ser473, The308), p-P70S6K, p-S6RP and p-4EBP1, and this inhibition was more pronounced when GDC-0980 was combined with T-DM1, 2) similarly the anti-proliferative activity of a combination of GDC-0980 plus T-DM1 was significantly higher by 3D-ON-TOP clonogenic assay following heregulin stimulation, 3) consistent with anti-proliferative effects of GDC-0980, the proportion of cells in the G1 phase of the cell cycle increased in HER2+ cell lines with a concomitant decrease in the S phase of their treatment with GDC-0980, 4) the initiation of apoptotic activity (annexin V) of GDC-0980 was significantly superior to that of an allosteric inhibitor of mTOR, RAD001. GDC-0980 also induced apoptotic markers like cleaved CASPASE3, cleaved PARP1, BIM in HER2+ BC cells and 5) a combination of GDC-0980 plus T-DM1 significantly blocked tumor growth to tumor regression in the HER2+/T-sensitive, HER2+/T-resistant and HER2+/PIK3CA mutated BC xenograft models. Along with its anti-tumor effect, this combination effectively decreased tumor angiogenesis (tumor micro-vessel density via CD31 staining). Conclusions: A combination of GDC-0980 plus T-DM1 significantly blocked in vitro and in vivo HER2+ breast tumor cells growth irrespective of PIK3CA mutation status. This strategy warrants further clinical investigation.

Citation Format: De PK, Carlson JH, Sun Y, Lin X, Friedman L, Dey N, Leyland-Jones B. A combination of dual inhibition in HER2-network by T-DM1 and GDC-0980 provides maximal antitumor efficacy in preclinical model of HER2+ breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-03-01.

Financial Conflicts of Interest and Study Results in Environmental and Occupational Health Research

OBJECTIVES

To date, there is no comprehensive analysis of the relationship between financial conflict of interest (COI) and a potential publication bias in environmental and occupational health studies.

METHODS

We analyzed original research articles published in 2012 in 17 peer-reviewed journals. Multivariable ordinal logistic regression models were developed to evaluate the relationship between financial COI and the study outcome.

RESULTS

Of the 373 studies included in the analysis, 17.2% had a financial COI associated with organizations involved with the processing, use, or disposal of industrial and commercial products, and studies with this type of COI were more likely to report negative results (Adjusted Odds Ratio = 4.31), as were studies with any COI associated with the military (employment or funding; Adjusted Odds Ratio = 9.15).

CONCLUSIONS

Our findings show a clear relationship between direction of reported findings and specific types of financial COI.

Abstract P4-08-04: Navigating genomic landscape to find a PI3K-signaling algorithm for a rational combinatin in precision medicine

Background: Treatment of BC is conventionally based on the presence/absence of ER/PR or HER2 status of the primary tumor. We have enriched this approach by including major genetic and proteomic changes in tumors of individual patients in order to develop a better treatment-rationale based on an alteration driven signaling algorithm. Methods: Genomic and proteomic data from 75 BC patients seen in our center were retrospectively analyzed. Patients were re-biopsied after consultation and samples were characterized (IHC for ER, PR, and HER2; FFPE samples for genomic [Foundation Medicine] and proteomic analyses [Theranostics]). In vivo studies were conducted using xenograft models. Results: Although alterations of PIK3CA, PIK3R1, AKT, PTEN, MDM2, MDM4, TSC1, mTOR and RICTOR are most frequently observed in our patients, there is a distinct pattern of alteration(s) of the PI3K pathway genes in different subtypes of BC. A total of 76 genes were altered in 48 ER+BC patients. In 79% of ER+BC patients the above mentioned PI3K pathway genes were altered. Analyzing the set of alterations of genes in individual patients, we observed that within these 48 patients 25% exhibited alterations in more than one node of the pathway; the most common combination (alterations) being the amplification/mutation of PIK3CA with the amplification of MDM2/4 genes. The percentage of patients belonging to HER2+ & TNBC exhibiting similar alterations in the PI3K pathway genes were significantly lower (∼40%). Our previous in vivo studies demonstrated that GDC-0980 and BEZ235 enhanced the antitumor activity of ABT888 plus carboplatin in TNBC or trastuzumab in HER2+ BC respectively and blocked the growth of established xenograft tumors by 80% to 90% with a concomitant decrease in tumor Ki67, pS6RP and CD31. Mechanistically the action of the PI3K-mTOR pathway targeted drug(s) was tested using cell line based models of BC subtypes pertaining to their respective genomic alterations. A combination of a pan-PI3K pathway inhibitor, GDC-0941 or isoform-specific inhibitors along with AI, trastuzumab, or HRD inhibitors (PARP) blocked proliferative signals and enhanced apoptosis (cleaved caspase3) in ER+/PIK3CA mutated, HER2+/PIK3CA mutated or PTEN-null TNBC cells respectively as demonstrated by WB, flow cytometry, cell proliferation, viability and cytotoxicity assays. A recent study demonstrated that exposure to chemotherapy induced a phenotypic shift or cell state transition towards a transient CD44Hi/CD24Hi chemotherapy-tolerant state, leading to the activation of downstream non-receptor tyrosine kinase signaling towards an emerging adaptive resistance (Goldman et al., Nature Comm. 2015). Hence drug combination(s) are being tested for their effect on CD44/CD24 expression levels, results of which will be presented in the meeting. Conclusion: Plotting the genetic alterations from the patient on the signaling landscape will be useful in cracking the code leading to improved treatment options. Patient specific in-depth plotting of genetic alterations of the PI3K-mTOR pathway and the relevance of these alterations in the context of (1) mechanisms of PI3K-mTOR pathway targeted drugs and (2) cell signaling are critical in determining choice of drugs in BC subtypes.

Citation Format: Carlson JH, Krie A, Williams C, Sun Y, Lin X, Williams K, Klein J, Friedman L, De P, Dey N, Leyland-Jones B. Navigating genomic landscape to find a PI3K-signaling algorithm for a rational combinatin in precision medicine. [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 P4-08-04.

Abstract PD3-04: PAK-1 amplified breast cancer cell lines are preferentially sensitive to PAK inhibition with G-5555

The small GTP-binding proteins Rac1 and Cdc42 stimulate activity of the serine/threonine kinase p21-activated kinase-1 (PAK-1) to drive growth factor signaling networks and Ras-driven tumorigenesis. Genomic amplification and over-expression of PAK1 are prevalent in luminal breast cancer and correlate with poor clinical outcome. Here we use a novel and selective small molecule inhibitor, G-5555, of the group I PAKs (PAK1, 2, and 3) to evaluate the importance of PAK1 in promoting growth of PAK1 amplified breast cancer cells. Cell lines with amplification of PAK1 were found to be more sensitive to PAK1 inhibition than non-amplified cell lines. Additionally, reverse phase protein array (RPPA) was used to assess the effects of PAK1 inhibition on a wide range of signaling pathways in both amplified and non-amplified cell lines. Reduced levels of phosphorylation of MEK S298 was observed in all cell lines exposed to G-5555 irrespective of amplification status, consistent with PAK1 inhibition in these cell lines. However, modulation of this downstream PAK1 substrate did not correlate with inhibition of cell proliferation or induction of cell death. Cell lines that showed inhibition of proliferation in response to G-5555 also showed enhanced levels of cell death along with apoptosis. Moreover, G-5555 reduced tumor growth in the PAK1 amplified MDA-MB-175 xenograft tumor model. Finally, we compared the in vitro activity of G-5555 with palbociclib, a recently approved inhibitor of the cyclin-dependent kinases CDK4 and CDK6, in PAK1 amplified luminal breast cancer cell lines. Our data supports PAK1 as an attractive target in PAK1 amplified cells and tumors and suggests that inhibiting PAK1 rather than CDK4/6 in this context may be a more attractive therapeutic strategy.

Citation Format: Ong CC, Blackwood E, Jakubiak D, Daemen A, Ramaswamy S, Heise C, Schmidt M, Sanders L, Wilson TR, Huw L, Ndubaku C, Rudolph J, Hoeflich KP, Friedman L, O'Brien T. PAK-1 amplified breast cancer cell lines are preferentially sensitive to PAK inhibition with G-5555. [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 PD3-04.

Risk factors associated with legal interventions

Background

Current research regarding injuries caused during interactions between police officers and civilians is conducted intermittently or on a very narrow sample frame which provides very little clinical information about the injuries suffered or the adverse outcomes. The aim of this study is to identify comorbid risk factors and describe acute outcomes of medically treated traumatic injuries occurring as a result of contact with law enforcement personnel.

Methods

For this retrospective study, patients injured as a result of contact with law enforcement personnel were identified using ICD-9 external cause of injury codes from medical record databases of patients treated in all hospitals and trauma units in Illinois between 2000 and 2009.

Results

A total of 836 cases injured as a result of contact with law enforcement personnel were identified. These patients were more likely to suffer from substance abuse, depression, schizophrenia, and paralytic disorders compared to the reference cases. Persons injured as a result of contact with law enforcement personnel were predominately injured from being man-handled, unarmed blows, firearms or being struck by a blunt object. Although the injury severity did not differ from the comparison group, these patients had longer lengths of hospitalization, a greater proportion of injuries to the back and spine, and a greater proportion required extended care in an intermediate care facility (not a jail) following discharge.

Conclusions

Although medical record data do not explain the detailed circumstances of the face-to-face encounters between law enforcement personnel and civilians, the data provide valuable information regarding who may be at risk of injury and the clinical features of injuries that are suffered following a legal intervention. Similar data systems should be considered to augment existing data systems.

Spatial clustering of occupational injuries in communities

OBJECTIVES

Using the social-ecological model, we hypothesized that the home residences of injured workers would be clustered predictably and geographically.

METHODS

We linked health care and publicly available datasets by home zip code for traumatically injured workers in Illinois from 2000 to 2009. We calculated numbers and rates of injuries, determined the spatial relationships, and developed 3 models.

RESULTS

Among the 23 200 occupational injuries, 80% of cases were located in 20% of zip codes and clustered in 10 locations. After component analysis, numbers and clusters of injuries correlated directly with immigrants; injury rates inversely correlated with urban poverty.

CONCLUSIONS

Traumatic occupational injuries were clustered spatially by home location of the affected workers and in a predictable way. This put an inequitable burden on communities and provided evidence for the possible value of community-based interventions for prevention of occupational injuries. Work should be included in health disparities research. Stakeholders should determine whether and how to intervene at the community level to prevent occupational injuries.

Urban crash-related child pedestrian injury incidence and characteristics associated with injury severity

OBJECTIVE

Describe age-based urban pedestrian versus auto crash characteristics and identify crash characteristics associated with injury severity.

MATERIALS AND METHODS

Secondary analysis of the 2004-2010 National Highway and Traffic Safety Administration database for Illinois. All persons in Chicago crashes with age data who were listed as pedestrians (n=7175 child age ≤19 yo, n=16,398 adult age ≥20 yo) were included. Incidence and crash characteristics were analyzed by age groups and year. Main outcome measures were incidence, crash setting, and injury severity. Multivariate logistic regression analysis was performed to estimate injury severity by crash characteristics.

RESULTS

Overall incidence was higher for child (146.6 per 100,000) versus adult (117.3 per 100,000) pedestrians but case fatality rate was lower (0.7% for children, 1.7% for adults). Child but not adult pedestrian injury incidence declined over time (trend test p<0.0001 for <5 yo, 5-9 yo, and 10-14 yo; p<0.05 for 15-19 yo, p=0.96 for ≥20 yo). Most crashes for both children and adults took place during optimal driving conditions. Injuries were more frequent during warmer months for younger age groups compared to older (χ(2)p<0.001). Midblock crashes increased as age decreased (p<0.0001 for trend). Most crashes occurred at sites with sub-optimal traffic controls but varied by age (p<0.0001 for trend). Crashes were more likely to be during daylight on dry roads in clear weather conditions for younger age groups compared to older (χ(2)p<0.001). Daylight was associated with less severe injury (child OR 0.93, 95% CI 0.87-0.98; adult OR 0.90, 95% CI 0.87-0.93).

CONCLUSION

The incidence of urban pedestrian crashes declined over time for child subgroups but not for adults. The setting of pedestrian crashes in Chicago today varies by age but is similar to that seen in other urban locales previously. Injuries for all age groups tend to be less severe during daylight conditions. Age-based prevention efforts may prove beneficial.

Mortality in cancer patients after a fall-related injury: The impact of cancer spread and type

BACKGROUND

Cancer patients are at an increased risk of dying following an injury, of which among the elderly is predominately caused by falling. In addition, patients with certain types of cancer are more prone to bone injury. However, studies are needed that examine the role of cancer site and metastasis on the relationship between cancer and death following traumatic injury.

METHODS

A total of 4201 cancer patients from 2000 to 2009 in the Illinois Hospital Discharge and Illinois Trauma Registry, and 4201 patients without cancer met eligibility criteria (e.g., fell and were injured; 50-96 years old). A multivariable logistic regression analysis was conducted to assess the relationship between cancer and death following traumatic injury, including models stratified by cancer site and metastasis.

RESULTS

The demographic characteristics, prevalence of comorbid conditions, and injury severity and type did not differ substantially between patients with and without diagnoses for cancer. In the main adjusted model, patients with cancer were more likely to die during the course of hospitalization after a fall than those without cancer (OR=2.58; CI 95%: 1.91-3.49). Patients with metastatic malignancies had a higher risk of in-hospital death than patients without metastasis (adjusted OR=3.59 and OR=2.18, respectively). Patients with diagnoses for all specific cancer sites, except prostate and breast, were also significantly more likely to die.

DISCUSSION

Cancer patients with and without spread over the age of 50 years are more likely to die in-hospital after a fall than elderly patients without cancer. However, this relationship may exist only for patients with specific cancer types.

Abstract P3-04-02: Absence of PTEN facilitates the anti-tumor efficacy of GDC-0980 in combination with ABT888 plus carboplatin in BRCA1-competent triple negative breast cancer

Introduction: PI3K pathway, in addition to its pro-proliferative and anti-apoptotic effects on tumor cells, is known to contribute to DNA-damage repair (DDR). We hypothesized that GDC-0980, a dual PI3K-mTOR inhibitor, will induce an efficient anti-tumor effect in BRCA-competent PTEN-null TNBC cells when combined with PARP inhibitor, ABT888 and carboplatin. We propose that in PTEN-null BRCA-competent TNBC model, the growth of TNBC tumor will be blocked due to the inhibition of (1) HR and NHEJ and (2) PI3K-mTOR pathway mediated survival signals following treatment with GDC-0980, when combined with PARP inhibitor (impaired DNA-SSB-repair) and carboplatin (increased DNA-DSB). Purpose: Here we tested the efficacy of a combination of GDC-0980 with ABT888 plus carboplatin in BRCA-competent PTEN-null model of TNBC. Methods: Athymic mice bearing PTEN-null TNBC xenograft tumors were treated with GDC-0980 alone or in combination with ABT888 and carboplatin. Results: Dual inhibition of PI3K and mTOR by GDC-0980 alone as well as in the presence of carboplatin plus ABT888 changed the state of the repair of DNA-damage in BRCA-competent PTEN null TNBC cells, which led to increased cellular apoptotic signals in addition to decreased survival/proliferative signals. GDC-0980 treatment led to DNA damage (increased pgH2AX), gain in PAR and a subsequent sensitization of BRCA-competent PTEN-null MDA-MB468 TNBC cells to ABT888 plus carboplatin with a time-dependent (1) decrease in proliferation signals (pAKT T308/S473, pP70S6K, pS6RP), PAR/PARP ratios, PAR/pgH2AX ratios, live/dead cell ratios, cell-cycle progression and clonogenic 3D growth and (2) increase in apoptosis markers (cleaved-caspase 3, 9, BIM, cleaved-PARP and annexinV positivity). These effects are more pronounced in MDA-MB468 than in RAS/RAF mutated MDA-MB231 cells. GDC-0980 alone and in combination with ABT888 plus carboplatin inhibited cell cycle progression, increased apoptosis, and decreased live/dead cell ratios in BRCA-competent PTEN null TNBC cells. GDC-0980 alone and in combination with ABT888 plus carboplatin attenuated anchorage -dependent and -independent clonogenic 3D growth comparatively more in BRCA-competent PTEN-null cells TNBC cells than MDA-MB231 cells. GDC-0980 in combination with ABT888 plus carboplatin blocked the growth of established PTEN-null TNBC tumors as compared to vehicle control(s) with a concomitant decrease in tumor Ki67 and CD31 IHC-stains. Conclusion: This is the first mechanism-based study to demonstrate that in BRCA-competent PTEN-null TNBC model, GDC-0980 enhanced antitumor activity of ABT888, in the presence of carboplatin by inhibiting DDR system in conjunction with the inhibition of PI3K-mTOR pathway-mediated proliferative, and anti-apoptotic signals. Considering (1) the importance of PARP as the target in TNBC, (2) the existence of a large percentage of BRCA-competent TN and/or basal type BC patients and (3) the high frequency of PTEN-null-ness in this subset of BC, this combination merits further investigation.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-04-02.

Abstract P6-05-09: Development of a predictive biomarker gene expression signature for the PIK3CA inhibitor, GDC-0032, in breast cancer cells

Introduction

The PI3-Kinase pathway is one of the most commonly mutated pathways in cancer and plays a major role in cell proliferation and survival. Mutations in PIK3CA, the gene encoding the p110 subunit of PI3K, are among the most common alterations in breast cancer, occurring in approximately 45% of luminal A, 30% of luminal B, 30% of HER2 positive and 8% of triple negative breast cancers. Additional pathway activating alterations include loss of PTEN, AKT mutations and overexpression of PIK3CA and HER2. Development of a pharmacodynamic biomarker is challenging with the more isoform specific PI3K inhibitors as multiple upstream pathways can funnel into common downstream immunohistochemical evaluable endpoints. In addition, phosphorylated epitopes are often labile and do not always lend themselves to immunohistochemical evaluation in the clinical setting. GDC-0032, which is currently under clinical investigation, is a class I PI3K inhibitor with 30-fold less inhibition on PI3K beta relative to PI3K alpha, and the development of a predictive and on-study pharmacodynamic signature may prove informative as compared to traditional IHC endpoints.

Methods

We screened a panel of 53 breast cancer cell lines, incorporating all subtypes, to GDC-0032 using the cell proliferation assay cell titer glo. To determine if there was a relationship between pathway activation and sensitivity to GDC-0032, we correlated response to PIK3CA mutations, loss of PTEN and HER2 overexpression. Using RNA sequencing, we compared the baseline gene expression between the sensitive and refractory cell lines. Next, to identify an on-study pharmacodynamic gene expression signature, we treated both sensitive and refractory cell lines with GDC-0032 and ran an in-house custom designed 800 gene NanoString breast cancer gene set that incorporated published PI3K pathway signatures, intrinsic subtyping genes and immunological related genes. Finally, the GDC-0032 signature was applied to a set of 160 FFPE breast cancer samples and overlaid with relevant biomarkers.

Results and Conclusions

Sensitivity to GDC-0032 correlated strongly with PI3K pathway activation including PIK3CA mutations and HER2 overexpression in breast cancer cells. Comparing baseline whole genome RNA expression of GDC-0032 sensitive and refractory cell lines, we identified 293 genes that were differentially expressed. Applying a more stringent statistical cutoff (greater than 2 fold difference and t-test less than 0.01) refined the gene list to 51 genes, which defined the baseline GDC-0032 sensitivity signature. Applying the 800 gene breast cancer NanoString panel to a set of 160 FFPE breast cancer samples, the GDC-0032 sensitivity signature correlated with luminal status and was enriched in PIK3CA mutant tumors. In conclusion, our in-house designed GDC-0032 sensitivity signature correlated strongly with PIK3CA mutations in clinical specimens. However the lack of complete correlation may identify tumors that have an activated PI3K pathway outside of PIK3CA mutations and/or HER2 amplification that may derive clinical benefit from GDC-0032.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-05-09.

Abstract P5-06-01: The PI3K inhibitor GDC-0941 combines with trastuzumab for superior anti-tumor efficacy in HER2+ breast cancer models

Background: PI3K-AKT-mTOR pathway signaling is important for the oncogenic function of HER2. Activating alterations of this pathway are frequently observed in HER2-enriched breast cancer and generally herald a poor response and resistance to trastuzumab (T). Purpose: Targeting the PI3K-AKT-mTOR pathway is an attractive strategy in HER2+ breast cancer that is refractory to trastuzumab. The hypothesis is that the suppression of this pathway by pan-PI3K inhibitor, GDC-0941 may lead to overcome trastuzumab-resistance. Experimental Design: The antiproliferative and HER2-mediated cellular signaling (pAKT, pP70S6K, pS6RP, p4EBP1 and p-ERK) effects of GDC-0941 alone and in combination with T were evaluated in HER2 amplified T-sensitive (BT474), T-resistant (BT474HR), and HER2 amplified/PIK3CA mutated (HCC1954, UACC893) BT cell lines by MTT assay and Western blots. Clonogenic growth was tested by 3D ON-TOP assay and apoptosis markers were also tested. Athymic mice bearing BT474 and BT474HR xenograft tumors were treated with GDC-0941 and T (alone and in combination). Results: (1) GDC-0941 exhibited in vitro cell killing activity in MTT assay with IC50's ranging from 0.35 μM to 1 μm and potency was augmented by the addition of T, (2) inhibition of phosphorylation of AKT(S473, T308), P70S6K, S6RP, and 4EBP1(T37/46, T70) was observed following GDC-0941 treatment, and the combination of GDC-0941 and T more effectively blocked the PI3K-AKT-mTOR pathway, (3) GDC-0941 treatment increased apoptosis markers (CL-CASPASE3 and annexinV positivity), (4) GDC-0941 dose-dependently blocked 3D-ON-TOP clonogenic growth of HER2+ cells. This effect was potentiated in the presence of T and (5) in vivo, the combination of GDC-0941 and T significantly reduced established tumor growth in both sensitive (82%) and resistant (79%) models with concomitant decrease of different PD markers. Conclusions: Our data suggest that 1) therapeutic targeting of the PI3K-AKT-mTOR signaling should be effective in abrogating resistance to T therapy in HER2+ BT, and 2) targeting both the HER2 and the PI3K signaling pathways is an attractive strategy to enhance the clinical efficacy of T therapy, as well as to prevent or delay the development of resistance.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-06-01.

Occupational amputations in Illinois 2000-2007: BLS vs. data linkage of trauma registry, hospital discharge, workers compensation databases and OSHA citations

BACKGROUND

Workplace amputation is a widespread, disabling, costly, and preventable public health problem. Thousands of occupational amputations occur each year, clustering in particular economic sectors, workplaces, and demographic groups such as young workers, Hispanics, and immigrants.

OBJECTIVES

To identify and describe work related amputations amongst Illinois residents that occur within Illinois as reported in three legally mandated State databases; to compare these cases with those identified through the BLS-Survey of Occupational Illnesses and Injuries (SOII); and to determine the extent of direct intervention by the Occupational Safety and Health Administration (OSHA) for these injuries in the State.

METHODS

We linked cases across three databases in Illinois - trauma registry, hospital discharge, and workers compensation claims. We describe amputation injuries in Illinois between 2000 and 2007, compare them to the BLS-SOII, and determine OSHA investigations of the companies where amputations occurred.

RESULTS

There were 3984 amputations identified, 80% fingertips, in the Illinois databases compared to an estimated 3637, 94% fingertips, from BLS-SOII. Though the overall agreement is close, there were wide fluctuations (over- and under-estimations) in individual years between counts in the linked dataset and federal survey estimates. No OSHA inspections occurred for these injuries.

CONCLUSIONS/RECOMMENDATIONS

Increased detection of workplace amputations is essential to targeting interventions and to evaluating program effectiveness. There should be mandatory reporting of all amputation injuries by employers and insurance companies within 24h of the event, and every injury should be investigated by OSHA. Health care providers should recognise amputation as a public health emergency and should be compelled to report. There should be a more comprehensive occupational injury surveillance system in the US that enhances the BLS-SOII through linkage with state databases. Addition of industry, occupation, and work-relatedness fields to the Electronic Health Record, the Uniform Billing form, and national health surveys would allow better capture of occupational cases for prevention and for assigning bills to the right payer source.