Artificial Intelligence-Assisted Loop Mediated Isothermal Amplification (AI-LAMP) for Rapid Detection of SARS-CoV-2

Until vaccines and effective therapeutics become available, the practical solution to transit safely out of the current coronavirus disease 19 (CoVID-19) lockdown may include the implementation of an effective testing, tracing and tracking system. However, this requires a reliable and clinically validated diagnostic platform for the sensitive and specific identification of SARS-CoV-2. Here, we report on the development of a de novo, high-resolution and comparative genomics guided reverse-transcribed loop-mediated isothermal amplification (LAMP) assay. To further enhance the assay performance and to remove any subjectivity associated with operator interpretation of results, we engineered a novel hand-held smart diagnostic device. The robust diagnostic device was further furnished with automated image acquisition and processing algorithms and the collated data was processed through artificial intelligence (AI) pipelines to further reduce the assay run time and the subjectivity of the colorimetric LAMP detection. This advanced AI algorithm-implemented LAMP (ai-LAMP) assay, targeting the RNA-dependent RNA polymerase gene, showed high analytical sensitivity and specificity for SARS-CoV-2. A total of ~200 coronavirus disease (CoVID-19)-suspected NHS patient samples were tested using the platform and it was shown to be reliable, highly specific and significantly more sensitive than the current gold standard qRT-PCR. Therefore, this system could provide an efficient and cost-effective platform to detect SARS-CoV-2 in resource-limited laboratories.

Abstract 4761: Lipidomic analysis of circulating lipids across the natural history of prostate cancer identifies aberrant ceramide metabolism

Background: Obesity is a well established risk factor not only for increased prostate cancer incidence, but for poorer survival from prostate cancer. However, there is limited knowledge on the role of the circulating lipidome in prostate cancer. In order to target lipid metabolism optimally, it is critical to understand the spectrum of changes in circulating lipid profiles and the association with clinical outcome across the natural history of prostate cancer.

Aim: To assess the relationship between the plasma lipidome and clinical outcome in localized and metastatic prostate cancer.

Methods: Liquid chromatography-tandem mass spectrometry was used to quantitate over 500 lipid species in plasma samples from 3 cohorts (1) 389 men with localized prostate cancer, (2) 44 men with metastatic hormone-sensitive prostate cancer (mHSPC), and (3) 137 men with metastatic castration-resistant prostate cancer (CRPC). Associations between circulating lipids with metastatic relapse, androgen-deprivation therapy (ADT) failure or overall survival for each relevant disease stage were examined by latent class analysis and cox regression.

Results: Circulating lipid profiles displaying elevated levels of ceramides were associated with metastatic relapse in localized prostate cancer (HR 5.8, 95% CI 3.0-11, P 1 × 10−6), early ADT failure in mHSPC (HR 2.4, 95% CI 1.1-5.3, P 0.03), and shorter overall survival in CRPC (HR 2.5, 95% CI 1.7-3.7, P 2 × 10−6). ADT failure in mHSPC and shorter overall survival in CRPC were also associated with elevated levels of other sphingolipids (sphingomyelins, hexosylceramides). The prognostic significance of the high risk lipid profiles in localized prostate cancer was independent of clinicopathological characteristics (lipid profile HR 4.7, 95%CI 2.4-9.3, P 7 × 10−6) when modeled with Gleason score (P<0.0001) and pathological stage (P<0.0001). Furthermore, the circulating lipid profiles were independent of metabolic factors (localized prostate cancer lipid profile HR 8.2, 95% CI 2.6-25, P 0.0003 when modeled with diabetes, statin, hypertension, body mass index [BMI]; CRPC lipid profile HR 2.6, 95% CI 1.7-3.8, P x10−6 when modeled with BMI).

Conclusion: Elevated circulating ceramides are associated with poorer clinical outcomes across the natural history of prostate cancer (from localized to metastatic hormone-sensitive to metastatic castration resistant prostate cancer). This demonstrates that aberrant lipid metabolism in the patients occurs early in prostate cancer and could be therapeutically targeted in prospective clinical trials to improve prostate cancer outcomes.

Citation Format: Lisa Glen Horvath, Hui-Ming Lin, Blossom Mak, Kate Mahon, Nicole Yeung, Maria Docanto, Peter Sutherland, andrew Shepherd, Winston Tan, Arun Azad, Manish Kohli, Peter Meikle, Lisa Butler. Lipidomic analysis of circulating lipids across the natural history of prostate cancer identifies aberrant ceramide metabolism [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4761.

Involving Urban Single Low-Income African American Mothers in Genomic Research: Giving Voice to How Place Matters in Health Disparities and Prevention Strategies

This article describes the process of using principles from community-based participatory action research to involve low-income, single, African American mothers on the south side of Chicago in genomic research, including as citizen scientists. The South Chicago Black Mothers' Resiliency Project used a mixed methods design to investigate how the stress of living in neighborhoods with high levels of violence affects mothers' mental and physical health. This article seeks to serve as a model for physicians and scholars interested in successfully involving low-income African American mothers in genomic research, and other health-related activities in ways that are culturally sensitive and transformative. The lives of Black mothers who struggle under interlocking systems of oppression that are often hidden from view of most Americans are at the center of this article. Therefore, we provide extensive information about the procedures used to collect the various types of data, the rationale for our procedures, the setting, the responses of mothers in our sample and methodological challenges. This study also has implications for the current COVID-19 pandemic and the need to train a corps of citizen scientists in health and wellness to avoid future extreme loss of life such as the 106,195 lives lost in the United States as of June 1, 2020.

Sex differences in corneal neovascularization in response to superficial corneal cautery in the rat

Sex-based differences in susceptibility have been reported for a number of neovascular ocular diseases. We quantified corneal neovascularization, induced by superficial silver nitrate cautery, in male and female inbred albino Sprague-Dawley, inbred albino Fischer 344, outbred pigmented Hooded Wistar and inbred pigmented Dark Agouti rats of a range of ages. Corneal neovascular area was quantified on haematoxylin-stained corneal flatmounts by image analysis. Pro-and anti-angiogenic gene expression was measured early in the neovascular response by quantitative real-time polymerase chain reaction. Androgen and estrogen receptor expression was assessed by immunohistochemistry. Male rats from all strains, with or without ocular pigmentation, exhibited significantly greater corneal neovascular area than females: Sprague-Dawley males 43±12% (n = 8), females 25±5% (n = 12), p = 0.001; Fischer 344 males 38±10% (n = 12) females 27±8% (n = 8) p = 0.043; Hooded Wistar males 32±6% (n = 8) females 22±5% (n = 12) p = 0.002; Dark Agouti males 37±11% (n = 9) females 26±7% (n = 9) p = 0.015. Corneal vascular endothelial cells expressed neither androgen nor estrogen receptor. The expression in cornea post-cautery of Cox-2, Vegf-a and Vegf-r2 was significantly higher in males compared with females and Vegf-r1 was significantly lower in the cornea of males compared to females, p<0.001 for each comparison. These data suggest that male corneas are primed for angiogenesis through a signalling nexus involving Cox-2, Vegf-a, and Vegf receptors 1 and 2. Our findings re-enforce that pre-clinical animal models of human diseases should account for sex-based differences in their design and highlight the need for well characterized and reproducible pre-clinical studies that include both male and female animals.

Self-reported risky sexual practices among adolescents and young adults in Botswana

Background

Adolescents and young adults account for more than one-third of incident Human Immunodeficiency Virus (HIV) infections globally. Understanding sexual practices of this high-risk group is critical in designing HIV targeted prevention programming.

Objectives

To describe self-reported risky sexual practices of adolescents and young adults aged 16–24 years from 30 Botswana communities.

Methods

Cross-sectional, self-reported age at sexual debut; number of sexual partners; condom and alcohol use during sex; intergenerational sex; and transactional sex data were collected. Modified Poisson estimating equations were used to obtain univariate and multivariate-adjusted prevalence ratios (PR) and 95% confidence intervals (CI) comparing engagement in different sexual practices according to gender, accounting for the clustered design of the study.

Results

Among the 3380 participants, 2311 reported being sexually active with more females reporting being sexually active compared to males (65% vs. 35%, respectively; p < 0.0001). In univariate analyses, female participants were more likely to report inconsistent condom use (PR 1.61; 95% CI 1.44–1.80), intergenerational sex (PR 9.00; 95% CI 5.84–13.88) and transactional sex (PR 3.46; 95% CI 2.07–5.77) than males, yet less likely to report engaging in sex before age 15 years (PR 0.59; 95% CI: 0.41–0.85), using alcohol around the time of intercourse (PR: 0.59; 95% CI 0.45–0.76) or having ≥ two partners in the last 12 months (PR 0.65; 95% CI 0.57–0.74).

Conclusions

Self-reported risky sexual practices of adolescents and young adults in Botswana differed significantly between males and females. Gender-specific risky sexual practices highlight the importance of developing tailored HIV prevention programming.

Abstract 112: Patient derived models reveal impact of the tumor microenvironment on therapeutic response

Prostate cancer (PCa) is the most common non-cutanenous cancer and the second leading cause of cancer-related death in American men. Androgen receptor (AR) is a hormone-activated transcription factor that plays an important role in both the development and progression of PCa. Androgen deprivation therapy is a common first-line therapy for disseminated disease. However, virtually all tumors become resistant to such therapy and the tumor recurs. Thus, there is a vital need for the development of novel, more effective drugs. One major hurdle in this aspect is the lack of adequate preclinical models. Current models do not effectively recapitulate the heterogeneity and the microenvironment of human PCa tumors, significantly hindering the ability to accurately predict therapeutic response. Our collaborative group has utilized and characterized a method to culture patient tumors ex vivo, termed Patient Derived Explant (PDE). This approach maintains the integrity of the native tumor microenvironment, tumor tissue morphology, and molecular signaling. Importantly, our PDE model can be manipulated both chemically (drugs/compounds) and genetically (shRNA) in order to determine specific reactions and mechanisms of response on individual tumor growth. Furthermore, with this model we can quantitatively assess drug efficacy on numerous parameters (i.e. AR levels, Ki67 staining, apoptosis screening, and desmoplasmic indices). Data to be discussed will assess the variances in response to AR-directed therapeutics and underlying mechanisms of action, while also utilizing TME characteristics as a means to predict response to therapy. In addition, we can potentially identify clinically relevant subpopulations of patients and molecularly profile their cultured tissue to uncover new pathways for therapeutic intervention. Thus, the PDE model allows for a comprehensive evaluation of individual tumors in their native microenvironment to ultimately develop more effective therapies. This study will have transformative clinical impact discerning novel metrics for the inclusion of precision medicine for advanced PCa.

Citation Format: Ayesha A. Shafi, Matthew J. Schiewer, Renée de Leeuw, Emanuela Dylgjeri, Peter A. McCue, Neelima Shah, Leonard Gomella, Costas Lallas, Edouard Trabulsi, Margaret Centerera, Theresa Hickey, Lisa Butler, Ganesh Raj, Wayne Tilley, Edna Cukierman, Karen E. Knudsen. Patient derived models reveal impact of the tumor microenvironment on therapeutic response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 112.

An Agricultural and Finance Intervention Improved Dietary Intake and Nutritional Status of Children Living in HIV-affected Households in Western Kenya (P10-129-19)

Objectives

To test whether an intervention that was shown previously to have improved food security, dietary intake of adults, and HIV health outcomes also improved dietary intake and nutritional status of children living in HIV-affected households.

Methods

The study was conducted in the Nyanza Region, Kenya where two health facilities were randomly assigned as intervention or control arms. The intervention included a human-powered water pump, a microfinance loan to purchase farm commodities, and training in sustainable farming practices and financial management. One hundred children (6 to 60 months of age) were enrolled in each arm from households with HIV-infected adults 18 to 49 years old on antiretroviral therapy and with access to surface water and land. Children were assessed beginning in April 2012 and every three months for one year. Data were collected on dietary intake, height, weight, and mid-upper arm circumference (MUAC). The difference in differences from first visit and in linear trends over visits were tested using fixed-effects regression models.

Results

Compared to the control arm, children in the intervention arm had a larger increase in weight at the 12-month visit (β: 0.42, 95% CI: 0.08, 0.76) and increase in MUAC at the 6-month visit (β: 0.28, 95% CI: 0.08, 0.49), with no difference in changes in height over time. Compared to the control arm, the intervention arm had a larger increasing linear trend over time in intake of staples (β: 0.22, 95% CI: 0.02, 0.44), fruits and vegetables (β: 0.42, 95% CI: 0.10, 0.75), and meat (β: 0.07, 95% CI: 0.03, 0.12), and a larger decreasing linear trend in intake of condiments (β: -0.16, 95% CI: -0.23, -0.09) and tea (β: -0.12, 95% CI: -0.19, -0.05), with no differences in intake of eggs, dairy and fat over time.

Conclusions

This intervention that improved food security, dietary intake, and HIV health outcomes of HIV-infected adults also improved dietary intake and nutritional status of children living in those households. Multisectoral agricultural and financial interventions have the potential to improve the nutritional status of HIV-affected children in rural Kenya and should be further explored.

Funding Sources

National Institute of Mental Health.

Preclinical investigation of a small molecule inhibitor of p300/CBP reveals efficacy in patient-derived prostate tumor explants

e16534

Background: Growth and survival of prostate cancer cells are initially dependent upon androgens, and androgen deprivation therapy (ADT) is used to control tumor growth. Unfortunately, resistance to ADT inevitably occurs, and patients relapse with lethal castrate-resistant prostate cancer (CRPC). Increased expression of the androgen receptor (AR) and constitutively active AR variants are hallmarks of CRPC, and treatments targeting aberrant AR signaling are urgently required. CCS1477 is an inhibitor of p300/CBP currently in a Phase I/IIa study for CRPC. CCS1477 enhances degradation of numerous cellular proteins including the AR and AR variants in prostate cancer cells. Our preclinical studies with this compound demonstrated potent single-agent efficacy of CCS1477 using in vitro and in vivo models of prostate cancer and, when used in combination, CCS1477 enhances the efficacy of enzalutamide, a clinical AR antagonist. Understanding the response of clinical tumors to CCS1477, and their potential adaptive evolution, is essential to personalize treatment and predict potential resistance mechanisms. Methods: To assess CCS1477 in human disease, we used a unique model in which clinical prostate tumors from radical prostatectomy are cultured as explants with maintenance of tissue integrity, cell proliferation and androgen signaling. Tumors from 13 patients were cultured in the absence or presence of CCS1477 (10µM) or enzalutamide (10µM) for 48 or 72 hours; micromolar doses were selected to account for altered small molecule uptake and penetration into tissues compared to cell lines, as previously reported. Proliferation, apoptosis and androgen signaling were all analyzed post-culture. Results: Whereas the tumor explants exhibited highly heterogenous proliferative responses to enzalutamide, tumors from all patients exhibited a marked antiproliferative response to CCS1477 (mean reduction in Ki67 immunoreactivity of > 90% compared to vehicle control; p < 0.0005). Culture with CCS1477 was associated with repression of androgen signaling in the prostate tissues, measured by expression and secretion of the clinical biomarker prostate specific antigen (PSA). Conclusions: The consistent and pronounced efficacy of CCS1477 in this patient-derived model would support further investigation of this class of epigenetic agents in the castrate-sensitive prostate cancer setting.

354. Evidence of Aspergillosis Among Patients With Influenza-Associated Hospitalizations—United States, 2005–2017

Background

Invasive aspergillosis primarily affects immunosuppressed persons, but it has also been observed in immunocompetent patients with severe influenza. Several case series suggest that severe influenza infection might be an under-recognized risk factor for aspergillosis. We examined the frequency of aspergillosis-related hospital discharge codes in a national surveillance database of influenza hospitalizations.

Methods

We analyzed laboratory-confirmed influenza-associated hospitalizations reported during 2005–2017 to Centers for Disease Control and Prevention (CDC)’s Influenza Hospitalization Surveillance Network (FluSurv-NET), which includes children and adults in 13 states. We obtained data on underlying conditions and clinical course through medical chart abstraction. We defined invasive aspergillosis cases as influenza hospitalizations with ≥1 of the following the International Classification of Diseases (ICD) 9th or 10th Clinical Modification discharge diagnosis codes: 117.3 (aspergillosis), 484.6 (pneumonia in aspergillosis), B44.0 (invasive pulmonary aspergillosis), B44.2 (tonsillar aspergillosis), and B44.7 (disseminated aspergillosis).

Results

Among 92,671 influenza hospitalizations, we identified 94 cases (0.1%) that had invasive aspergillosis codes. Characteristics of patients were: 60% male (56/94), 72% white race (60/83), and median age 58 years [interquartile range (IQR) 41–67]. Influenza A accounted for 80% (75/94) of cases. Seventy-nine percent (74/94) received antiviral therapy. Underlying conditions included 63% (59/94) immunocompromising condition, 51% (48/94) chronic lung disease, 22% (21/94) renal disease, and 15% (14/94) asthma. Forty-eight percent of patients (45/94) required intensive care. At the time of discharge, 60% (56/94) were diagnosed with pneumonia and 14% (13/94) died.

Conclusion

Over one-third of patients with invasive aspergillosis did not have a documented immunosuppressive condition. ICD codes are likely an imperfect way to identify invasive aspergillosis, and further studies are needed to characterize risk factors and verify diagnoses for aspergillosis among patients with severe influenza.

Disclosures

E. J. Anderson, NovaVax: Grant Investigator, Research grant. Pfizer: Grant Investigator, Research grant. AbbVie: Consultant, Consulting fee. MedImmune: Investigator, Research support. PaxVax: Investigator, Research support. Micron: Investigator, Research support. K. Talbot, sanofi pasteur: Investigator, Research support. Gilead: Investigator, Research support. MedImmune: Investigator, Research support. Seqirus: Scientific Advisor, Consulting fee. MedImmune: Scientific Advisor, Consulting fee.

Ex vivo Culture and Lentiviral Transduction of Benign Prostatic Hyperplasia (BPH) Samples

To assess oncogenic potential, classical transformation assays are based on cell line models. However, cell line based models do not reflect the complexity of human tissues. We thus developed an inducible expression system for gene expression in ex vivo human tissues, which maintain native tissue architecture, such as epithelia and stroma. To validate the system, we transduced and expressed known tumor suppressors (p53, p33ING1b), oncoproteins (RasV12, p47ING3), or controls (empty vector, YFP) in ex vivo prostate tissues, then assessed proliferation by immunohistochemistry of markers (H3S10^phos). Herein, we describe how to generate lentiviral vectors and particules, successfully transduce human prostate tissues, induce exogenous gene expression, and assess cellular proliferation.

Report from the fifth international consensus meeting to harmonize core outcome measures for atopic eczema/dermatitis clinical trials (HOME initiative)

This is the report from the fifth meeting of the Harmonising Outcome Measures for Eczema initiative (HOME V). The meeting was held on 12-14 June 2017 in Nantes, France, with 81 participants. The main aims of the meeting were (i) to achieve consensus over the definition of the core domain of long-term control and how to measure it and (ii) to prioritize future areas of research for the measurement of the core domain of quality of life (QoL) in children. Moderated whole-group and small-group consensus discussions were informed by presentations of qualitative studies, systematic reviews and validation studies. Small-group allocations were performed a priori to ensure that each group included different stakeholders from a variety of geographical regions. Anonymous whole-group voting was carried out using handheld electronic voting pads according to predefined consensus rules. It was agreed by consensus that the long-term control domain should include signs, symptoms, quality of life and a patient global instrument. The group agreed that itch intensity should be measured when assessing long-term control of eczema in addition to the frequency of itch captured by the symptoms domain. There was no recommendation of an instrument for the core outcome domain of quality of life in children, but existing instruments were assessed for face validity and feasibility, and future work that will facilitate the recommendation of an instrument was agreed upon.

Developing Media to Promote Community Awareness of Early Detection of Kaposi’s Sarcoma in Africa

Abstract 44

Purpose

Despite overt presentation on the skin, most Kaposi’s sarcoma (KS) in Africa is diagnosed too late for treatment to be effective. Training health care workers to recognize KS early can increase knowledge, but is only clinically impactful if providers actually encounter early KS—that is, if patients with early KS present to care. Indeed, recent work from Zimbabwe has shown that facility-based KS training failed to increase early diagnosis, which is unsurprising given the public’s lack of awareness of KS. We hypothesized that educating affected populations about KS is critical to making progress in early detection and that enhanced community awareness about KS can be achieved through exposure to common media.

Methods

Working in Uganda, we used community-engaged research to learn about health-related behaviors in the context of skin disease, craft a culturally appropriate educational theme regarding the detection of KS, and develop three forms of media. We interacted with survivors of KS, HIV-infected patients, facility-based and community health workers, traditional healers, and media professionals. We tested our media among adults at community-based venues in rural Uganda. Participants were randomly assigned to be exposed to one of the three media and were evaluated for changes in knowledge and attitudes concerning KS before and after exposure to media.

Results

In comics, 90-second radio plays, and a 10-minute film, we developed a three-part theme that was aimed at the public: “look,” meaning to regularly examine one’s skin and mouth; “show” to bring to the attention of a health care worker any skin changes; and “test” to remind providers about skin biopsy for diagnosis. Among the 240 participants who were exposed to media, median age was 30 years, 50% were women, 6% were HIV infected, and 60% were literate. Exposure to media resulted in increases in the ability to recognize and/or name KS (+47%), awareness that anyone is at risk for KS (+15%), and knowledge of how to prevent KS from becoming a substantial problem (+34%).

Conclusion

Featuring the theme, “Look, show, and test,” we developed media—comics, radio plays, and film—for the public in Africa about the early detection of KS. Exposure to these media resulted in increases in knowledge and changes in attitudes concerning KS. Although the increases in knowledge were not large, they may be as much as can be expected from a single exposure. Optimal outcomes will likely require multiple exposures and facilitated discussions. Media elements are freely available online.

AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST

No COIs from the authors.

An analysis of multiple biomarkers to better predict prostate cancer metastasis and death after radical prostatectomy

54

Background: Identification of potentially lethal disease at the time of diagnosis with localized prostate cancer (PCa) remains a significant clinical issue despite a plethora of candidate biomarkers. This study evaluates a range of biomarkers previously associated with biochemical relapse (BR) in localized PCa to determine whether a combined expression model can improve detection of clinically significant cases. Methods: The Australian PCa Research Centre NSW has completed 23 studies of molecular biomarkers associated with BR in a well-described localized PCa cohort (n=324, median followup 16 years). 12 studies were excluded due to missing data. Each biomarker was analyzed as a marker for metastatic-free survival (MFS) and prostate cancer specific survival (PCSS) and then used to develop a prognostic model for clinical outcomes incorporating clinico-pathological factors. This model is currently being validated in an independent cohort. Results: The PCa cohort experienced 39 metastatic relapses (12%) and 23 PCa deaths (7%). Of 12 biomarkers (AR, AZPG1, C0S, Cyclin D1a, Cyclin D1b, E6AP, H3K18Ac, H3K4me2, Ki67, p53, PML, SGTA) assessed, only AZGP1 and Ki67 were associated with MFS (HR 2.9, 95% CI, 1.4-5.6; P=0.002, and HR 1.2, 95% CI, 1.0-1.4; P=0.03, respectively) and PCSS (HR 4.2, 95% CI, 1.7-10.5; P=0.002; and HR 1.2, 95% CI, 1.0-1.5; P=0.04, respectively). The combined panel of AZGP1 and Ki67 was an independent predictor of MFS (HR 1.9, 95% CI, 1.1-3.2; P=0.01), and PCSS (HR 3.3, 95% CI, 1.5-7.3; P=0.002) when modeled with known clinicopathological variables. The panel was more robust in predicting MFS and PCSS compared to the individual biomarkers alone and superior to other prognostic models (See table). Data from the validation cohort will be available for the meeting. Conclusions: Our novel signature of AZPG1 and Ki67 improves existing prognostication tools in predicting PCa metastasis and death. [Table: see text]

High expression of TROP2 characterizes different cell subpopulations in androgen-sensitive and androgen-independent prostate cancer cells

Progression of castration-resistant tumors is frequent in prostate cancer. Current systemic treatments for castration-resistant prostate cancer only produce modest increases in survival time and self-renewing Tumor-Initiating Cells (TICs) are suspected to play an important role in resistance to these treatments. However it remains unclear whether the same TICs display both chemo-resistance and self-renewing abilities throughout progression from early stage lesions to late, castration resistant tumors. Here, we found that treatment of mice bearing LNCaP-derived xenograft tumors with cytotoxic (docetaxel) and anti-androgen (flutamide) compounds enriched for cells that express TROP2, a putative TIC marker. Consistent with a tumor-initiating role, TROP2^high cells from androgen-sensitive prostate cancer cell lines displayed an enhanced ability to re-grow in culture following treatment with taxane-based chemotherapy with or without androgen blockade. TROP2 down-regulation in these cells reduced their ability to recur after treatment with docetaxel, in the presence or absence of flutamide. Accordingly, in silico analysis of published clinical data revealed that prostate cancer patients with poor prognosis exhibit significantly elevated TROP2 expression level compared to low-risk patients, particularly in the case of patients diagnosed with early stage tumors. In contrast, in androgen-independent prostate cancer cell lines, TROP2^high cells did not exhibit a differential treatment response but were characterized by their high self-renewal ability. Based on these findings we propose that high TROP2 expression identifies distinct cell sub-populations in androgen-sensitive and androgen-independent prostate tumors and that it may be a predictive biomarker for prostate cancer treatment response in androgen-sensitive tumors.

An international comparison of retinopathy of prematurity grading performance within the Benefits of Oxygen Saturation Targeting II trials

Purpose

To investigate whether the observed international differences in retinopathy of prematurity (ROP) treatment rates within the Benefits of Oxygen Saturation Targeting (BOOST) II trials might have been caused by international variation in ROP disease grading.

Methods

Groups of BOOST II trial ophthalmologists in UK, Australia, and New Zealand (ANZ), and an international reference group (INT) used a web based system to grade a selection of RetCam images of ROP acquired during the BOOST II UK trial. Rates of decisions to treat, plus disease grading, ROP stage grading, ROP zone grading, inter-observer variation within groups and intra-observer variation within groups were measured.

Results

Forty-two eye examinations were graded. UK ophthalmologists diagnosed treat-requiring ROP more frequently than ANZ ophthalmologists, 13.9 (3.49) compared to 9.4 (4.46) eye examinations, P=0.038. UK ophthalmologists diagnosed plus disease more frequently than ANZ ophthalmologists, 14.1 (6.23) compared to 8.5 (3.24) eye examinations, P=0.021. ANZ ophthalmologists diagnosed stage 2 ROP more frequently than UK ophthalmologists, 20.2 (5.8) compared to 12.7 (7.1) eye examinations, P=0.026. There were no other significant differences in the grading of ROP stage or zone. Inter-observer variation was higher within the UK group than within the ANZ group. Intra-observer variation was low in both groups.

Conclusions

We have found evidence of international variation in the diagnosis of treatment-requiring ROP. Improved standardisation of the diagnosis of treatment-requiring ROP is required. Measures might include improved training in the grading of ROP, using an international approach, and further development of ROP image analysis software.

Prevalence and factors associated with recent intimate partner violence and relationships between disability and depression in post-partum women in one clinic in eThekwini Municipality, South Africa

Intimate partner violence (IPV) experienced by pregnant and post-partum women has negative health effects for women, as well as the foetus, and the new-born child. In this study we sought to assess the prevalence and factors associated with recent IPV amongst post-partum women in one clinic in eThekwini Municipality, South Africa, and explore the relationship between IPV, depression and functional limitations/disabilities. Past 12 month IPV-victimisation was 10.55%. Logistic regression modelled relationships between IPV, functional limitations, depressive symptoms, socio-economic measures, and sexual relationship power. In logistic regression models, overall severity of functional limitations were not associated with IPV-victimisation when treated as a continuous overall score. In this model relationship power (aOR0.22, p = 0.001) and depressive symptoms (aOR1.26, p = 0.001) were significant. When the different functional limitations were separated out in a second model, significant factors were relationship power (aOR0.20, p = 0.001), depressive symptoms (aOR1.20, p = 0.011) and mobility limitations (aOR2.96, p = 0.024). The study emphasises that not all functional limitations are associated with IPV-experience, that depression and disability while overlapping can also be considered different drivers of vulnerability, and that women’s experience of IPV is not dependent on pregnancy specific factors, but rather wider social factors that all women experience.

Abstract 1152: Lipid elongation: an unexplored therapeutic target in prostate cancer

Dysregulated lipid metabolism is one of the hallmarks of cancer, particularly for prostate cancer (PCa). PCa cells exhibit distinctive metabolic features such as upregulation of enzymes involved in de novo synthesis, uptake and beta-oxidation of lipids, which promote prostate cancer growth, metastasis, and drug resistance. Androgen signalling is a major driver of both PCa growth and lipid metabolism in PCa cells, however the precise effects of androgens on cellular lipid composition and the molecular pathways by which androgens regulate lipid metabolism in PCa cells are yet to be elucidated. In this study we investigated the effect of androgens on the lipid composition of PCa cell membranes and the enzymes involved in lipid metabolism, and explored the influence of these enzymes on tumour cell behaviour such as cell migration, proliferation and attachment. PCa cell lines (AR positive and negative) were cultured in the absence or presence of androgens or the anti-androgen enzalutamide, and changes in intact phospholipid species were assessed by ESI-MS/MS-based lipidomics. This analysis revealed a complexity of changes in phospholipid profiles in response to androgen treatment. Strikingly, elongation of the fatty acyl chains was consistently observed for multiple phospholipid classes in response to the androgens mibolerone or 5α-dihydotestosterone, whereas inhibition of elongation was observed in the presence of enzalutamide. Transcriptional analysis of critical lipid metabolism pathways revealed that the enzymes that catalyse lipid elongation (ELOVLs) were markedly induced by androgens in multiple PCa cell lines, and siRNA depletion of these enzymes, either alone or in combination, reversed the androgen-induced fatty acyl elongation phenotype. The androgenic regulation of ELOVL enzymes was confirmed in clinical PCa cohorts and in primary tumours cultured as explants. Targeting ELOVL gene expression also significantly attenuated the tumorigenic properties of PCa cells. ELOVL downregulation decreased LNCaP cell migration, and adhesion to fibronectin. Furthermore, ELOVL knock down significantly decreased three-dimensional spheroid growth of LNCaP cells using a hang drop assay. The impact of these enzymes on the lipid profile of PCa cell membrane and cell viability, adhesion and migration suggests that they may represent promising and previously unexplored therapeutic targets.

Citation Format: Zeyad D. Nassar, Margaret M. Centenera, Jelle Machiels, Samuel J. Polacek, Katarzyna Bloch, Wayne D. Tilley, Luke A. Selth, Johannes V. Swinnen, Lisa Butler. Lipid elongation: an unexplored therapeutic target in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1152. doi:10.1158/1538-7445.AM2017-1152

A continuous quality improvement intervention to improve the effectiveness of community health workers providing care to mothers and children: a cluster randomised controlled trial in South Africa

BACKGROUND

Community health workers (CHWs) play key roles in delivering health programmes in many countries worldwide. CHW programmes can improve coverage of maternal and child health services for the most disadvantaged and remote communities, leading to substantial benefits for mothers and children. However, there is limited evidence of effective mentoring and supervision approaches for CHWs.

METHODS

This is a cluster randomised controlled trial to investigate the effectiveness of a continuous quality improvement (CQI) intervention amongst CHWs providing home-based education and support to pregnant women and mothers. Thirty CHW supervisors were randomly allocated to intervention (n = 15) and control (n = 15) arms. Four CHWs were randomly selected from those routinely supported by each supervisor (n = 60 per arm). In the intervention arm, these four CHWs and their supervisor formed a quality improvement team. Intervention CHWs received a 2-week training in WHO Community Case Management followed by CQI mentoring for 12 months (preceded by 3 months lead-in to establish QI processes). Baseline and follow-up surveys were conducted with mothers of infants <12 months old living in households served by participating CHWs.

RESULTS

Interviews were conducted with 736 and 606 mothers at baseline and follow-up respectively; socio-demographic characteristics were similar in both study arms and at each time point. At follow-up, compared to mothers served by control CHWs, mothers served by intervention CHWs were more likely to have received a CHW visit during pregnancy (75.7 vs 29.0%, p < 0.0001) and the postnatal period (72.6 vs 30.3%, p < 0.0001). Intervention mothers had higher maternal and child health knowledge scores (49 vs 43%, p = 0.02) and reported higher exclusive breastfeeding rates to 6 weeks (76.7 vs 65.1%, p = 0.02). HIV-positive mothers served by intervention CHWs were more likely to have disclosed their HIV status to the CHW (78.7 vs 50.0%, p = 0.007). Uptake of facility-based interventions were not significantly different.

CONCLUSIONS

Improved training and CQI-based mentoring of CHWs can improve quantity and quality of CHW-mother interactions at household level, leading to improvements in mothers' knowledge and infant feeding practices.

TRIAL REGISTRATION

ClinicalTrials.Gov NCT01774136.

The Effects of Music and Movement Opportunity on the Analogical Reasoning Performance of African American and White School Children: A Preliminary Study

This study sought tofurther establish that contextualfactors informed by cultural experiences could influence performance on a learning task. Low-income African American and middle-income White children listened to stories read under two contexts thatdiffered in the degree to which movement and music were integrated with the presentation of the stories. The high-movement expressive (HME) context allowedfor children to coordinate movement with a musical accompaniment while listening to the stories, and the low-movement expressive (LME) context allowed for little movement opportunity and no music was played. Performance was measured via a multiple-choice test designed to assess the amount of information the children processed about the stories. Results revealed that whereas African American children perform better under the HME than the LME context, White children perform better under the LME than the HME context. The results are discussed in relation to future research.