Abstract 4975: Breast tumor expression of DARC/ACKR1 and impacts on disease progression and immune cell recruitment in the tumor microenvironment

The Duffy Antigen Receptor for Chemokines (DARC/ACKR1) is an atypical chemokine receptor which promiscuously binds chemokines of both CC and CXC chemokine families. DARC/ACKR1 maintains homeostatic levels of chemokines in circulation through its expression on erythrocytes, and in tissues participates in chemokine transport, where chemokines are transported across the cell layer to help establish chemokine gradients. Establishment of these chemokine gradients is essential for proper immune cell trafficking.

In our recent study, we have shown that DARC/ACKR1 is expressed on the tumor epithelium, and through in silico analysis of data from the Cancer Genome Atlas (TCGA), that higher DARC/ACKR1 expression is positively and significantly correlated with tumor-associated leukocyte abundance when using CIBERSORT deconvolution methods. Specifically, higher DARC/ACKR1 expression was linked with increases in B cell, T cell, monocyte and macrophage populations. Higher DARC/ACKR1 expression is also significantly associated with better survival outcomes, across all breast cancer molecular subtypes.

To further evaluate DARC/ACKR1 expression and influences on the breast TME, we have employed multiple approaches to characterize how DARC/ACKR1 impacts immune cell recruitment and subsequent infiltration into the tumor.

In our patient cohort, we have recently completed Hyperion imaging mass cytometry staining of tumors that have been scored by IHC as DARC/ACKR1 high or low expressing. We used a panel of approximately 30 markers, including structural, immune, and other markers of interest. Following imaging, we have used cell segmentation software to quantify marker expression on a cell-by-cell basis. Using this method, we are able to conduct single-cell analyses of our markers of interest, while also retaining the spatial composition of the cells. We have used the tSNE algorithm to identify cell populations that cluster uniquely within DARC/ACKR1 high or low tumor expressing groups, specifically identifying different clusters of immune cell populations, which show different spatial expression patterns in our comparison groups.

In addition to investigations of immune cell recruitment to the TME, we have also developed a novel DARC/ACKR1 breast cancer transgenic mouse model to study how disease progression may differ with differing DARC/ACKR1 phenotypes. Briefly, DARC -/- female mice were crossed with the male C3(1)Tag +/0 breast cancer transgenic mouse to generate DARC +/-, C3(1)Tag +/0 male mice. These males were subsequently backcrossed to DARC -/- females, to generate the target DARC/ACKR1 +/- or -/-, C3(1)Tag+ mice. These mice show evidence of early disease beginning at 3.5 months of age, and progress to advanced disease by 5 months of age. We have collected tumor tissue and blood specimens from mice ranging from 3.5 to 7 months of age, to characterize disease progression over time between our DARC/ACKR1 expressing and non-expressing groups. We have observed differences in tumors characteristics between our DARC/ACKR1 expressing groups, and upon histological and immunofluorescent evaluation, we have begun to observe differences in immune cell recruitment, following similar patterns to what we observed in our in silico and patient cohort analyses.

Citation Format: Rachel Martini, Brittany Jenkins, Dorrah Deeb, Hiranmayi Ravichandran, Paula Ginter, Esther Cheng, Syed Hoda, Dhananjay Chitale, Haythem Ali, Eleanor Walker, Jessica Bensenhaver, Olivier Elemento, Nancy Manley, Lisa Newman, Melissa Davis. Breast tumor expression of DARC/ACKR1 and impacts on disease progression and immune cell recruitment in the tumor microenvironment [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 4975.

THU0329 SAFETY, TARGET ENGAGEMENT, AND INITIAL EFFICACY OF AVID200, A FIRST-IN-CLASS POTENT AND ISOFORM-SELECTIVE INHIBITOR OF TGF-BETA 1 AND 3, IN PATIENTS WITH DIFFUSE CUTANEOUS SYSTEMIC SCLEROSIS (DCSSC): A PHASE 1 DOSE ESCALATION STUDY

Background:

AVID200 is a novel, potent TGF-beta receptor ectodomain-based trap designed to selectively neutralize TGF-beta 1 and 3. These two isoforms have been implicated as central mediators of the pathogenesis of systemic sclerosis (SSc). AVID200 avoids inhibition of TGF-beta 2, the isoform that supports normal cardiac function and hematopoiesis.

Objectives:

This first-in-human study (AVID200-01;NCT03831438) is a Phase 1, open label, multicenter, cohort dose-escalation trial designed to evaluate safety, tolerability, pharmacokinetic (PK) profile, pharmacodynamic (PD) effects, target engagement, and preliminary efficacy in patients with diffuse cutaneous SSc (dcSSc).

Methods:

Eligible patients must have dcSSc of <5 years (y) duration and a modified Rodnan Skin Score (MRSS) ≥15. AVID200 at dose levels of 1, 3, 9, or 15 mg/kg IV is administered every 2 weeks (Q2W) for 6 weeks (3 doses). Patients tolerating dosing and who have not experienced disease worsening during the initial Treatment Period may receive up to 6 additional doses Q2W (Extension Period). The ability of AVID200 to selectively sequester its target is assessed in plasma by TGF-beta quantification per ELISA and a cell-based functional readout. Expression of biomarkers of TGF-beta inhibition and genes correlating with MRSS are assessed.

Results:

The first 2 dose cohorts have completed treatment: male/female 3 each, median age 61y (range 45-70), median MRSS at baseline 31 (range 23-39). Recruitment into cohort 3 is complete. AVID200 was well tolerated with no dose limiting toxicities or serious adverse events (SAEs). AEs, all considered possibly related, included single cases of Grade 1 dizziness and CPK elevation, and Grade 2 anemia. All patients demonstrated a decline in MRSS at 6 weeks by 3, 4, and 9 points in Cohort 1, and 2, 8, and 9 points in Cohort 2. Four of 6 patients demonstrated continued decrease in MRSS 12 weeks after the last dose, with all patients showing a decline in MRSS relative to baseline at this timepoint by 7, 6, and 7 points in Cohort 1 and 4, 8, and 13 points in Cohort 2. AVID200 in plasma engaged endogenous activated TGF-beta and potently neutralized signaling from exogenous TGF-beta 1 and 3, but not TGF-beta 2, across the treatment period. PD effects in skin biopsies, including expression of markers of SSc activity, TGF-beta activity, and myofibroblast-associated genes were assessed. Five of 6 patients showed decreased expression of PD biomarker genes, THBS1 and MS4A4A, comparing end of treatment biopsies to baseline, and all patients showed a decline in SERPINE1 expression, a marker gene for TGF-beta activity. Clustering of RNA-seq expression data showed close coregulation of COMP, THBS1, SERPINE1, LOXL, COL10A1, COL11A1, COL12A1, CTGF, and CDH11, suggesting that blocking TGF-beta inhibits this group of profibrotic genes. Single-cell sequencing data show that expression of these genes is upregulated by subsets of SSc fibroblasts.

Conclusion:

AVID200 at doses of 1 and 3 mg/kg was well-tolerated in this first study in dcSSc patients. Evidence of anti-fibrotic effects as indicated by rapid, persistent and clinically meaningful declines in MRSS was observed in all patients, as well as AVID200 target engagement and modulation. Recruitment into additional dose and extension cohorts is ongoing. Together, these clinical data support selective TGF-beta 1 and 3 inhibition by AVID200 as a promising therapeutic approach for dcSSc.

Disclosure of Interests:

Robert Lafyatis Grant/research support from: Forbius, Consultant of: Certa Therapeutics, Forbius, FBM Therapeutics, Robert Spiera Grant/research support from: Roche-Genetech, GSK, Boehringer Ingelheim, Chemocentryx, Corbus, Forbius, Sanofi, Inflarx, Consultant of: Roche-Genetech, GSK, CSL Behring, Sanofi, Janssen, Chemocentryx, Forbius, Mistubishi Tanabe, Robyn Domsic Consultant of: Forbius, Anna Papazoglou: None declared, Colin Ligon Grant/research support from: Forbius, Christina Mae Zinger Morse: None declared, Jean-François Denis Employee of: Forbius, Margaret Davis Employee of: Forbius, Tina Gruosso Employee of: Forbius, Gilles Tremblay Employee of: Forbius, Maureen O’Connor McCourt Employee of: Forbius, Sandra Sinclair Employee of: Forbius, Jonathan Delara Employee of: Forbius, Krista Alvarado Employee of: Forbius, Debra Wood Consultant of: Forbius, Symphogen, Paul Nadler Consultant of: Forbius, Symphogen, Karyopharm, Elizabeth Volkmann Grant/research support from: Forbius, Corbus Pharmaceuticals, Consultant of: Boehringer Ingelheim, Forbius, Speakers bureau: Boehringer Ingelheim

Abstract B058: In silico and in vivo analysis of the Duffy Antigen Receptor for Chemokines (DARC) in the breast tumor microenvironment

In clinic, we observe that women of African descent have higher incidence rates of breast cancer (BC). These women are disproportionately diagnosed with the most aggressive subtype of BC, triple-negative BC, compared to women belonging to any other ancestry groups. To investigate factors driving this disparity, our work focuses on the tumor microenvironment (TME), specifically through the lens of an atypical chemokine receptor. The Duffy Antigen Receptor for Chemokines (DARC) is a nonsignaling, atypical chemokine receptor that binds two structural classes of chemokines. DARC modulates chemokine availability in circulation and participates in chemokine transport in tissues, to recruit immune cells back to sites of inflammation. DARC additionally serves as a portal of entry for the malaria-causing parasite Plasmodium vivax. In Sub-Saharan Africa, where malaria is endemic, a regulatory variant arose removing DARC expression from red blood cells (RBCs). This mutation, known as the Duffy-Null allele, was highly beneficial in this population, and quickly rose to fixation. Despite being called Duffy-Null, these individuals retain DARC expression in other cell types, only lacking expression on RBCs. Knowing that the Duffy-Null allele is prevalent in this population of women, we aim to investigate how DARC tumor expression and Duffy-Null status impacts the TME in silico through analysis of The Cancer Genome Atlas (TCGA) data, and in vivo through establishment of mouse models that depict Duffy-Null status in the BC TME. Using TCGA data, we see that DARC tumor gene expression is significantly lower among African-Americans compared to Whites. Using the CIBERSORT online platform, we quantified tumor-associated leukocyte (TAL) abundance in the TME. Overall, we found that tumors with high DARC expression have significantly higher total TAL abundance (p &lt; 0.0001), and that DARC expression and TAL abundance are positively and significantly correlated (R = 0.545, p &lt; 0.0001). Specifically, DARC expression influenced levels of B cell, T cell, monocyte and macrophage population in the TME. In our mouse models, we have utilized the C3(1)Tag BC transgenic mouse model, alongside a DARC knock-out mouse. To better recapitulate the Duffy-Null phenotype in our mouse model, our approach is to generate a BC/Duffy-Null bone marrow derived (BMD) chimera, where a DARC+/-; C3(1)Tag+/0 recipient will receive bone marrow from a DARC -/- donor. The resulting chimera mice will retain DARC expression in all cells, aside from bone marrow-derived cells from the null donor. In the C3(1)Tag line, disease onset is at approximately 12 weeks, at which time we will assess changes in disease progression in our chimeras compared to controls by collecting total number of tumors, tumor location, tumor size and weight, and hematoxylin and eosin staining of tumor sections, and immune cell infiltration quantification.

Citation Format: Rachel Martini, Brittany Jenkins, Clayton Yates, Lisa Newman, Nancy Manley, Melissa Davis. In silico and in vivo analysis of the Duffy Antigen Receptor for Chemokines (DARC) in the breast tumor microenvironment [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr B058.

Abstract C033: Racial differences in the associations between luminal master regulator transcription factor expression and breast cancer survival

Purpose: Women of African ancestry in the United States are more likely to die from breast cancer than their European counterparts. While prior studies suggest differences in the frequency of hormone receptor-negative disease as an underlying cause, recent studies report higher race-based mortality rates in patients with hormone receptor-positive, luminal breast cancer. Here we explore biologic factors that may underly this disparity by comparing racial differences in the level, functional activity, and prognostic significance of 3 master transcriptional regulators of mammary luminal differentiation.

Patients and Methods: Medical records and tissues from 555 patients (293 European and 262 African ancestry) diagnosed with Stage 0 to IV breast cancer, from 2001 to 2010 at a major medical center in East North Carolina, were analyzed for the expression of functional biomarkers of luminal differentiation including estrogen receptor (ESR1), and pioneer transcription factors FOXA1 and GATA3. Differential comparison of protein expression was integrated with network-level gene expression analysis (22% of cohort) to define predictive correlations with race and survival.

Results: Univariate and multivariate odds ratios combined with area under the curve receiver operator characteristics show significant differences in predictive activity of these functional biomarkers based on race and survival—ESR1 (EA OR= 0.47, p = 5e-04; AA OR= 0.77, p = 0.22), FOXA1 (EA OR= 0.38, p= 1.4e-04; AA OR = 0.53, p = 1.3e-02), and GATA3 (EA OR= 0.36, p= 3.7e-06, AA OR= 0.57, p= 0.51)—and uncover genes in the downstream regulons of these biomarkers that strongly correlate either with genetic ancestry or overall survival.

Conclusion: Transcriptional regulatory networks linked to mammary luminal differentiation reveal race-specific differences in master regulatory activity that may underlie tumor characteristics contributing to racial disparities in outcome. These biomarkers and their downstream regulons represent important targets to explore intrinsic mechanisms that drive breast cancer survival disparities.

Citation Format: Jung S. Byun, Sandeep K. Singhal, Sam Park, Dae Ik Yi, Tingfen Yan, Ambar Caban, Alana Jones, Partha Mukhopadhyay, Sara Gil Hernandez, Stephen Hewitt, Lisa A. Newman, Melissa Davis, Jorge Sepulveda, Adrianna De Siervi, Anna Napoles, Nasreen Vohra, Kevin Gardner. Racial differences in the associations between luminal master regulator transcription factor expression and breast cancer survival [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C033.

Abstract B107: Race-specific gene expression patterns in triple-negative breast cancer (TNBC) cases

Historically, incidence rates of breast cancer (BC) have been higher among Caucasian (CA) women compared to African-American (AA) women, until convergence of these rates in the mid 2000s. Conversely, when accessing mortality rates among these women, AA women have reported higher rates of mortality from BC since the mid 1980s. Despite a decline in BC mortality over the past 30 years, the mortality rate of disease among AA women remains to be significantly higher than that of their CA counterparts. When molecular subtypes of BC are considered, prevalence of Triple-Negative BC (TNBC), the most aggressive subtype of BC, is found to be higher among AA women. TNBC prevalence on the global scale shows highest levels of TNBC across Africa, and higher rates can also be observed across the African diaspora. To address this, we sought out to identify race-specific differences among TNBC cases. We completed RNA sequencing on a cohort of 75 cases, where 42 of the cases were AA, and 33 were CA. The dataset was dichotomized by if the individuals had received neoadjuvant chemotherapy prior to surgery and specimen collection, where we had 60 treatment naïve cases (31 AAs and 29 CAs) and the remaining 15 had received neoadjuvant chemotherapy (residual tumors; 11 AAs and 4 CAs). We assessed self-reported race, ancestry estimation from matched DNA samples into and TNBC molecular subtyping from matched DNA samples into our DE gene expression analyses. Among treatment naïve tumors, we identified over 1000 genes that were significantly differentially expressed (DE) between race groups (p &lt; 0.05). To further analyze our race-specific gene set, we used Ingenuity Pathway Analysis (IPA) to investigate relevant pathways and regulators specific to our gene set. Using the causal network analysis, we see that biological functions such as cellular organization and assembly show significant enrichment in our gene set, and that the NFkB complex is a top regulator predicted to be activated in our AA treatment naïve cases compared to CAs. For those individuals who had received neoadjuvant chemotherapy, we identified 13 genes that are significantly different between race groups, and these DE genes are distinct from those identified in our treatment naïve analyses.

Citation Format: Rachel Martini, Jason White, Akanksha Verma, Olivier Elemento, Lisa Newman, Manne Upender, Clayton Yates, Melissa Davis. Race-specific gene expression patterns in triple-negative breast cancer (TNBC) cases [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr B107.

Ancestry-specific gene expression profiles in TNBC tumors

1547

Background: Due to persistent disparities in breast cancer mortality, there has been a renewed focus on investigating tumor biology. Deeper exploration has exposed distinctions in tumor biology based upon self-reported race and ancestry. The disparities associated with Triple Negative Breast Cancer (TNBC) across the modern African Diaspora suggests that there is a genetic ancestry connection between its aggressive tumor biology and clinical outcomes. Understanding this connection could hold the key to improving clinical outcomes in this group. Methods: We investigated 75 TNBC primary tumors using Self-Reported Race (SRR) groups: African American (AA, n = 42) and European American (EA, n = 33). Using best practices established by TCGA, we analyzed bulk RNA sequencing to measure changes in genome-wide expression levels. We next quantified global ancestry in a novel manner using RNAseq variants using 1000 Genomes as the reference data. We then identified African and European ancestry-associated genes using a logistic regression (adjusted FDR p < 0.05) between quantified ancestry and gene expression levels. Results: We identified > 150 genes associated with quantified African ancestry. We also found using quantified ancestry was a more robust method to screen for differentially expressed genes than SRR. Using an updated TNBC subtyping method, we noted higher incidences of Basal-like 2 tumors in AAs. Pathway analyses indicated several canonical cancer pathways; including, TP53, NFKB1 and AKT, have altered functionality in patients of African descent. For example, TP53-associated genes were activated in TNBC tumors of AA versus EA. This upregulation, rather than loss of function, is suggestive of polymorphic and/or ancestry-specific expression regulation, likely driven by population-private genetic variants. Lastly, we used TCGA data to validate a subset of African ancestry-specific genes that were upregulated in AA patients in our cohort. Specifically, PIM3, ZBTB22 and PPP2R4 each retained significant upregulation, in our cohort, but also TNBC tumors from TCGA (p = 0.0018, 0.023 and 0.022, respectively). Conclusions: Our study has uncovered ancestry-specific gene expression profiles in TNBC tumors. The distinct distribution of TNBC subtypes and altered functional oncologic pathways are evidence that biological underpinnings in TNBC can be driven by shared genetic ancestry. These findings emphasize the need to investigate patient populations of various ancestral origins in order to fully appreciate the molecular diversity in tumor biology for precision of disease management.

Effect of Kaiso on immune signaling of breast cancer exosomes

3088

Background: Exosomes are communication vesicles that act as mediators of intracellular transfer of genetic information, an important role in intercommunication between tumor cells and immune cells. However, the mechanism underlining this cell-cell communication is not well understanding, particularly in African American breast cancer patients. Recently, our lab has demonstrated that Kaiso, a novel bi-modal transcription factor is highly expressed in African American breast cancer and notably, high Kaiso expression correlates with breast cancer aggressiveness and the disparity in survival outcomes of breast cancer patients of African American compared to European American patients. However, the differential expression and biological consequences of Kaiso in immune signaling of breast cancer exosomes has not been studied yet. Herein we demonstrate the biological role of Kaiso in immune signaling in breast cancer exosomes. Methods: In this study we utilized Nanostring immune profiling technology along with multiple in vitro and in vivo assays were used to study the role of Kaiso in breast cancer immune escape. Results: Nanostring pan cancer immune profiling demonstrated that European American breast cancer exosomes exhibited higher expression of TILs markers, T cell activation markers and CD8+T Cells markers compared to African American (p < 0.05, FDR), while we observed an increase in the expression of the anti-phagocytic molecule CD47 in breast cancer patient exosomes of African American compared to European American patients. In addition to that CD47 and SIRP-α (Signal Regulatory Protein) are highly expressed in Kaiso-scrambled MDA-MB-231 cells (sh-Scr) and exosomes, whereas THBS1, which is a regulator of CD47 expression and is regarded as angiogenesis inhibitor is significantly increased in sh-Kaiso MDA-231 cells and exosomes. Additionally, we observed that Kaiso directly binds methylated sequences in the promoter region of CD47 and THBS1 by ChIP assay. Furthermore, in vivo sh-Kaiso cells injected into athymic mice exhibited delayed tumor formation after four weeks with smaller tumor size as compared to sh-SCR cells (p < 0.05), and we observed higher expression of THBS1 with lower expression of CD47 and SIRP-α molecules by IHC and exosomes isolated from in vivo tumors (p < 0.05), indicating that Kaiso is associated with macrophage mediated immune escape. Conclusions: These findings demonstrate the important role of kaiso in immune signaling through exosomes which may be related with more aggressive cancer phenotype in breast cancer, especially in African Americans.

Identification of Distinct Heterogenic Subtypes and Molecular Signatures Associated with African Ancestry in Triple Negative Breast Cancer Using Quantified Genetic Ancestry Models in Admixed Race Populations

Triple negative breast cancers (TNBCs) are molecularly heterogeneous, and the link between their aggressiveness with African ancestry is not established. We investigated primary TNBCs for gene expression among self-reported race (SRR) groups of African American (AA, n = 42) and European American (EA, n = 33) women. RNA sequencing data were analyzed to measure changes in genome-wide expression, and we utilized logistic regressions to identify ancestry-associated gene expression signatures. Using SNVs identified from our RNA sequencing data, global ancestry was estimated. We identified 156 African ancestry-associated genes and found that, compared to SRR, quantitative genetic analysis was a more robust method to identify racial/ethnic-specific genes that were differentially expressed. A subset of African ancestry-specific genes that were upregulated in TNBCs of our AA patients were validated in TCGA data. In AA patients, there was a higher incidence of basal-like two tumors and altered TP53, NFB1, and AKT pathways. The distinct distribution of TNBC subtypes and altered oncologic pathways show that the ethnic variations in TNBCs are driven by shared genetic ancestry. Thus, to appreciate the molecular diversity of TNBCs, tumors from patients of various ancestral origins should be evaluated.

Functional diversity of marine megafauna in the Anthropocene

Marine megafauna, the largest animals in the oceans, serve key roles in ecosystem functioning. Yet, one-third of these animals are at risk of extinction. To better understand the potential consequences of megafaunal loss, here we quantify their current functional diversity, predict future changes under different extinction scenarios, and introduce a new metric [functionally unique, specialized and endangered (FUSE)] that identifies threatened species of particular importance for functional diversity. Simulated extinction scenarios forecast marked declines in functional richness if current trajectories are maintained during the next century (11% globally; up to 24% regionally), with more marked reductions (48% globally; up to 70% at the poles) beyond random expectations if all threatened species eventually go extinct. Among the megafaunal groups, sharks will incur a disproportionate loss of functional richness. We identify top FUSE species and suggest a renewed focus on these species to preserve the ecosystem functions provided by marine megafauna.

Skin cancer multiplicity in lung transplant recipients: a prospective population-based study

BACKGROUND

Lung transplant recipients are at high risk of skin cancer, but precise annual incidence rates of treated skin cancers per patient are unknown.

OBJECTIVES

To perform a prospective assessment of the total burden of histologically confirmed squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) and associated factors in lung transplant recipients.

METHODS

A population-based cohort of 125 Queensland lung transplant recipients aged 18 years and over, recruited between 2013 and 2015, were followed to the end of 2016. All underwent dermatological skin examinations at baseline and annually thereafter and patients self-reported all interim treated skin cancers, which were verified against pathology databases. Standard skin cancer risk factors were obtained via questionnaire, and details of medications were acquired from hospital records.

RESULTS

During a median follow-up time of 1·7 years, 29 (23%) and 30 (24%) lung transplant recipients with a median duration of immunosuppression of 3·3 years developed SCC and BCC, respectively. The general population age-standardized incidence rates of SCC and BCC were 201 and 171 per 1000 person-years, respectively (based on first primary SCC or BCC during follow-up); however, on accounting for multiple primary tumours, corresponding incidence rates were 447 and 281 per 1000 person-years. Risk of multiple SCCs increased around sixfold in those aged ≥ 60 years and in those with previous skin cancer, and increased around threefold in those treated with the antifungal medication voriconazole. Multiple BCC risk rose threefold from age 60 years and tenfold for patients with previous skin cancer.

CONCLUSIONS

Lung transplant recipients have very high incidence of multiple primary skin cancers. Close surveillance and assiduous prevention measures are essential. Linked Comment: Proby and Harwood. Br J Dermatol 2020; 183:416-417.

Abstract P1-03-08: In vivo investigation of the Duffy antigen receptor for chemokines (DARC/ACKR1) and tumor-infiltrating immune cells in the breast tumor microenvironment

Recruitment of immune cells and subsequent infiltration of these cell populations into the tumor microenvironment (TME) can influence disease prognosis, and potential treatments for patients. Through studying the TME of breast tumors, we have investigated factors that modify immune cell recruitment and infiltration into the tumor area. In our recently published work, we analyzed the TCGA breast cancer (BC) cohort, where we have identified the Duffy Antigen Receptor for Chemokines / Atypical Chemokine Receptor 1 (DARC/ACKR1) as a putative driver of immune cell recruitment and infiltration to the breast TME.

DARC/ACKR1 is an atypical chemokine receptor that promiscuously binds both the CC and CXC classes of chemokines. On the surface of red blood cells in circulation, DARC/ACKR1 maintains homeostatic levels of chemokines in circulation by binding chemokines when levels are high, and releasing them back into circulation when levels lower. In tissues, DARC/ACKR1 participates in chemokine transcytosis, working to move chemokines across the cell layer to establish chemokine gradients necessary for recruitment of respective immune cell populations.

Through in silico analysis of TCGA BC cohort data, we performed CIBERSORT TME deconvolution methods to approximated levels of 22 tumor-associated immune cell populations. We showed that as DARC/ACKR1 expression increased in breast tumors, we also saw a significant increase in number of tumor-associated immune cells (p&lt;0.0001). When looking at the specific cell populations, we found that B cells, T cells, monocytes and macrophage populations were significantly different between high, mid and low DARC/ACKR1 expressing tumors.

To continue investigation of these findings in vivo, we developed a novel DARC/ACKR1 breast cancer transgenic mouse model. Briefly DARC/ACKR1 -/- mice were crossed with the C3(1)Tag breast cancer transgenic mouse model. Breast cancer Tg+; DARC/ACKR1 +/- males were then backcrossed to DARC/ACKR1 -/- females, to generate target female mice that were BC Tg+, and either DARC/ACKR1 +/- or DARC/ACKR1 -/-. Disease progression in the C3(1)Tag line follows a similar pattern to ductal carcinoma in situ (DCIS), through progression to advanced invasive disease. All mice develop DCIS beginning at approximately 12 weeks of age, and 100% of mice are affected with invasive disease by 6 months of age.

We have collected tissue from mice from DCIS stage of disease through invasive disease. Blood was collected from each mouse, and the plasma was used to quantify the circulating chemokine profile. Tumors and mammary tissue were collected from each mouse and weighed, alongside spleen, liver, and potential metastatic tumor sites. Tumors and mammary glands were processed for immunohistochemistry and immunofluorescent staining procedures, where DARC/ACKR1 expression, immune cells, structural markers and chemokines of interest were assayed. We also took representative sections from each genotype of interest for Hyperion imaging mass cytometry analysis, where we can simultaneously analysis 27 different immune, structural and other markers of interest. From our preliminary results from in silico TCGA analysis, we expect to see changes in immune cell recruitment and infiltration, specifically in quantity of immune cells recruited and infiltrating, and in the composition of the tumor associated immune cells between our DARC/ACKR1 expression or non-expressing BC Tg+ mice.

Citation Format: Rachel Martini, Lisa Newman, Nancy Manley, Melissa Davis. In vivo investigation of the Duffy antigen receptor for chemokines (DARC/ACKR1) and tumor-infiltrating immune cells in the breast tumor microenvironment [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-03-08.

The impact of translated reminder letters and phone calls on mammography screening booking rates: Two randomised controlled trials

INTRODUCTION

Participation in mammographic screening for breast cancer in Australia is approximately 54% among the general population, but screening among women from some culturally and linguistically diverse (CALD) backgrounds is lower. BreastScreen Victoria apply strategies to increase screening including reminder letters and phone calls; however, these are usually provided in English. Using intervention strategies generated from the Ophelia (OPtimise HEalth LIteracy and Access) community co-design process, translated mammography reminder letters and in-language phone calls were tested within two randomised control trials (RCTs).

METHODS AND ANALYSIS

Women aged 50-75 years who were due for their 2-yearly screening mammography (for RCT#1) or were under-screened, i.e. ≥27 months since last screen (for RCT#2) were randomised into intervention or control groups. RCT#1 compared sending women routine reminder letters (English only) with translated (Arabic or Italian) letters. RCT#2 compared reminder telephone calls to women in their preferred language (Arabic or Italian) to no telephone call. The primary outcome for each trial was screening booking rates within 14-days. Primary outcomes were tested using Pearson's chi-square test. Rates within language group (incidence ratio: IR) were compared using the Cochran-Mantel-Haenszel test.

RESULTS

For RCT#1 (letters) 1,032 women were randomised into the intervention arm or to usual care. Uptake of screening bookings was similar between both groups, with no differences observed by language group. For RCT#2 (phone calls), 195 women were randomised to the intervention group or to usual care. Overall, 64.2% of women in the intervention arm and 6% in the control arm booked a screening appointment within 14 days (p<0.0001). The IR (95%CI) of booking was 10.1 (3.9, 26.3) times higher among Italian women, and 11.6 (2.9, 46.5) times higher among Arabic women in the intervention compared to usual care groups.

DISCUSSION AND CONCLUSION

A service improvement initiative derived from community members and breast screen providers was found to be highly effective. This evidence informed the service provider, BreastScreen Victoria, who have implemented these improvements into routine practice to improve screening among CALD groups and reduce health inequalities.

Clinical Utility of Weekly Laboratory Testing in the Outpatient Management of Preeclampsia and Gestational Hypertension

Objective  To investigate the utility of obtaining weekly laboratory testing in patients managed as an outpatient for gestational hypertension and preeclampsia without severe features. Study Design  A multisite retrospective cohort study was performed evaluating preterm women diagnosed with gestational hypertension/preeclampsia managed in an outpatient setting between gestational ages of 23 ^0/7 and 36 ^6/7 . Patients were divided into two groups: weekly laboratory evaluation (laboratories group) and a no laboratories group. The primary study outcome was composite maternal morbidity including more than one of the following: development of severe features, HELLP syndrome, eclampsia, placental abruption, maternal intensive care unit admission, or maternal death. Results  A total of 204 patients were included in this study, laboratories group ( n  = 120) and no laboratories group ( n  = 84). The laboratories group was older (28.8 vs. 26.6 years, p  = 0.02), had a higher rate of chronic hypertension (44 [36.7%] vs. 17 [20.2%], p  = 0.01), and more often experienced the primary composite outcome (53 [44.2%] vs. 24 [28.5%], p  = 0.02). No patients in our cohort were delivered for abnormal laboratory values. Conclusion  This study found that weekly laboratory testing may have minimal clinical utility in the outpatient management protocol in monitoring patients with mild gestational hypertension or preeclampsia. Delivery was guided by other clinical factors.

Perceptions of Animal Welfare With a Special Focus on Turkeys

Meat consumption and public concern for farm animal welfare are increasing, despite limited public understanding of agriculture and animal welfare. Turkey is important in U.S. holiday meal traditions and turkey meat is a frequently consumed processed product (i.e., lunchmeat). However, little is known about public perceptions and knowledge of commercial turkeys. An online survey was administered to 1,695 respondents in November 2018 to examine U.S. (1) demographic factors affecting meat consumption, selection of labeled meat products, and concern for animal welfare, (2) public knowledge of turkeys, and (3) concerns regarding the welfare of turkeys and other species. A total of 95% of respondents consumed meat and 10% hunted for some of the meat they consumed. Meat consumption frequency depended on region of residence, income level, gender, age, and whether respondents hunted. Of the meat consumers, 86% purchased turkey products. More meat consumers looked for the USDA organic label (39%) and the Non Genetically Modified Organism (GMO) project label (38%) than animal-welfare food labels (14%) when buying meat products. More pet owners (39%) than non-pet owners (25%) looked for animal welfare food labels. Being a pet owner increased the probability of being concerned about farm animal welfare. Concern for the commercial turkey was similar to concern for other farm animal species; self-reported knowledge of turkey production was low (mean score 2.64; scale of 1 to 7, 7 = highest). Turkey welfare concerns (mean score; rank from 1 to 5; 5 = least concerning) included poor nutrition (2.471) and illness (2.508), followed by housing (2.732), hot or cold weather (3.308) and transportation (3.981). Turkey welfare attributes that respondents cared the most about (mean score; scale of 1–5, 5 = cared the least) included space to move around (2.366), followed by veterinary health and wellness (2.680), ability to perform natural behavior (2.812), no feather loss or visible injuries (3.304), and decreased aggression (3.837). Demographic factors are important determinants of meat consumption and animal welfare concern. Public knowledge of turkey production is limited, despite a large percentage of the population purchasing turkey products.

Androgen Receptor and ALDH1 Expression Among Internationally Diverse Patient Populations

Purpose

Population-based incidence rates of breast cancers that are negative for estrogen receptor (ER), progesterone receptor, and human epidermal growth factor receptor 2/neu (triple-negative breast cancer [TNBC]) are higher among African American (AA) compared with white American (WA) women, and TNBC prevalence is elevated among selected populations of African patients. The extent to which TNBC risk is related to East African versus West African ancestry, and whether these associations extend to expression of other biomarkers, is uncertain.

Methods

We used immunohistochemistry to evaluate estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2/neu, androgen receptor and aldehyde dehydrogenase 1 (ALDH1) expression among WA (n = 153), AA (n = 76), Ethiopian (Eth)/East African (n = 90), and Ghanaian (Gh)/West African (n = 286) patients with breast cancer through an institutional review board–approved international research program.

Results

Mean age at diagnosis was 43, 49, 60, and 57 years for the Eth, Gh, AA, and WA patients, respectively. TNBC frequency was higher for AA and Gh patients (41% and 54%, respectively) compared with WA and Eth patients (23% and 15%, respectively; P < .001) Frequency of ALDH1 positivity was higher for AA and Gh patients (32% and 36%, respectively) compared with WA and Eth patients (23% and 17%, respectively; P = .007). Significant differences were observed for distribution of androgen receptor positivity: 71%, 55%, 42%, and 50% for the WA, AA, Gh, and Eth patients, respectively (P = .008).

Conclusion

Extent of African ancestry seems to be associated with particular breast cancer phenotypes. West African ancestry correlates with increased risk of TNBC and breast cancers that are positive for ALDH1.

Single-Room Ward Design and Its Impact on Service and Patient Outcomes: An Evaluation Study

BACKGROUND

Evidence suggests that single-room inpatient wards are associated with better patient outcomes than open-room wards but little is known about the impact on adverse events, patient satisfaction, and clinician experiences.

METHODS/PURPOSE

We evaluated the impact of a new inpatient single-room orthopaedic ward on patient and clinician outcomes using a medical record audit; patient, nurse, and medical doctor surveys; and nonparticipant observations in a tertiary hospital in Sydney, Australia.

RESULTS

The audit (1,569 patients; 819 open-room ward and 750 new single-room ward) revealed unchanged adverse event rates and fewer emergency calls after the move to a single-room ward. Survey responses from nurses, medical doctors, and patients were positive. Observations suggested that clinicians devised solutions to potential threats to patient safety.

CONCLUSION

The single-room ward design did not negatively impact on patient and clinician outcomes and was preferred by them. Clinicians organized their work to ensure patient safety.

A-65 Verbal Abilities May Influence Performance in Assessment of Verbal Short-Term Memory Tasks

Objective

Examine whether verbal abilities may help explain the learning strategies people employ when completing a short-term verbal memory task.

Methods

The assessment records of 296 American Veterans with diverse neuropsychiatric conditions were analyzed using Exploratory Factor Analyses. There were no exclusion criteria. All participants completed the Benton Serial Digit Learning Test – 9 Digits (SDL-9) and Visual Naming (VisNam), Sentence Repetition (SenRep), Controlled Word Association (COWA), and Token Tests of the Multilingual Aphasia Examination (MAE). Individual assessment instruments were factored using Principal Component Analyses (PCA). A three-factor solution of the SDL-9 was co-factored with the verbal components of the MAE to identify common sources of variance.

Results

A three-factor solution of the SDL-9 separated trials into three overlapping factors consisting of early (SDL-9_Early), middle (SDL-9_Middle), and late (SDL-9_Late) trials. Co-factoring the three new scales with the verbal components of the MAE produced a four-factor model explaining 67.85% of the shared variance: 1) SenRep loaded with SDL-9_Early, 2) COWAT loaded with SDL-9_Middle and SDL-9_Late, 3) Token loaded with SDL-9_Late, and 4) Vis Nam loaded with SDL-9_Late.

Conclusions

The results suggest that individuals may engage verbal abilities differently as they progress from simpler to more difficult verbal short-term memory tasks. It appears performance in early trials is mostly associated with rote repetition and performance on middle trials is mostly associated with verbal fluency, while performance on the late trials is associated with a combination of verbal fluency, auditory comprehension, and conceptual organization/naming. This may therefore indicate a shift in learning strategy to meet increased cognitive demands.