Perinatal ethanol exposure affects cell populations in adult dorsal hippocampal neurogenic niche

Neurodevelopment is highly affected by perinatal ethanol exposure (PEE). In the adult brain, neurogenesis takes place in the dentate gyrus (DG) of the hippocampus and in the subventricular zone. This work aimed to analyze the effect of PEE on the cellular types involved in adult dorsal hippocampal neurogenesis phases using a murine model. For this purpose, primiparous female CD1 mice consumed only ethanol 6% v/v from 20 days prior to mating and along pregnancy and lactation to ensure that the pups were exposed to ethanol throughout pre- and early postnatal development. After weaning, pups had no further contact with ethanol. Cell types of the adult male dorsal DG were studied by immunofluorescence. A lower percentage of type 1 cells and immature neurons and a higher percentage of type 2 cells were observed in PEE animals. This decrease in type 1 cells suggests that PEE reduces the population of remnant progenitors of the dorsal DG present in adulthood. The increase in type 2 cells and the decrease in immature neurons indicate that, during neurodevelopment, ethanol alters the capacity of neuroblasts to become neurons in the adult neurogenic niche. These results suggest that pathways implicated in cell determination are affected by PEE and remain affected in adulthood.

Association of palliative care management and survival after chemotherapy discontinuation in patients with advanced pancreatic adenocarcinoma: A retrospective single-centre observational study

BACKGROUND

Palliative care (PC) is integrated into standard oncology care. However, its clinical impact at the end of life remains unclear in pancreatic adenocarcinoma (PA). We aimed to describe the end-of-life care pathway and to assess whether PC referral influences survival after chemotherapy discontinuation (CD) among advanced PA patients.

METHODS

This retrospective single-centre observational study was conducted among deceased patients with advanced PA who had received chemotherapy between January 1, 2016, and December 31, 2021. Baseline characteristics, the timing of PC referral and events after CD were collected. The primary outcome was time from CD to death.

RESULTS

Among the 148 included patients, 53.4% (n = 79) received PC, mostly late after the CD (n = 133, 89.9%), 16.9% (n = 25) received chemotherapy in the last 14 days of life and 75.6% died at the hospital. None received PC in the 8 weeks following the diagnosis. PC referral significantly increased PC department admissions (p < 0.001) and decreased medical unit admissions (p < 0.001). The median survival after the CD was 35 days (IQR: 19-64.5). PC referral was associated with increased survival after CD (HR: 0.65 [0.47-0.90], p = 0.010, Cox) and after adjusting (HR: 0.65 [0.42-0.99], p = 0.045, Cox).

CONCLUSION

The study suggests that PC may be associated with longer survival after CD in advanced PA patients. However, PC is underused, and patients are referred late in their care pathway.

Clinical outcomes in patients with bicuspid aortic valves and ascending aorta dilatation equal or above 50mm

Background

Little is known about clinical outcomes in patients with bicuspid aortic valve (BAV) and ascending aortic diameters ≥50 mm where the elective surgical-indication zone begins.

Purpose

To assess incident aortic dissection (AoD), post-surgical survival and guideline implementation.

Methods

Multi-center retrospective study of BAV patients (≥18 years) with maximal root or tubular-ascending aortic diameters ≥50mm detected by transthoracic echocardiography at baseline. Ascertainment of aortic surgery, AoD and death was carried-out at their respective institutions. The primary outcome was AoD: “confirmed” AoD by surgery or death certificate, or “possible” AoD defined as sudden cardiac death of unknown cause by death certificate. Secondary outcomes were aortic surgery, post-surgical survival and guideline implementation.

Results

We included 506 consecutive BAV patients, mean age 61±14 years, 83% men, mean maximal aortic diameter 52±2 mm at baseline, ascending aorta was the most common segment ≥50mm (85%). During a median follow-up of 7.7 years, 356 (71%) underwent elective surgery (89% of class 1 patients). Early-surgery (≤6 months from baseline) occurred in 195 patients and 311 patients remained “under-surveillance”. Surgery under-surveillance (&gt;6 months from baseline) occurred in 161/311 (52%) patients at 2.6 [IQR: 1.5–4.7] years of follow-up. Surgical mortality was 1.4%. Ten-year post-surgical survival was &gt;90% and similar between early-surgery and surgery under-surveillance (p=0.8). Of 8 AoD events, 3 confirmed and 5 possible (all occurring in unoperated patients under-surveillance), 5 events occurred with maximal aortic baseline diameter ≥55 mm and/or &gt;1 year without clinical follow-up; therefore, under guideline non-compliance. Incidence of confirmed plus possible aortic dissection was 0.37% per year with size 50–54mm, 1.13% per year between 55–59mm, and 10.41% per year with size ≥60mm. Aortic stenosis was associated with AoD (p=0.04) and all-cause death in unoperated patients (p=0.001).

Conclusions

Our results suggest that BAV patients can be safely followed as per guidelines after aortic diameters enter the elective surgical zone (≥50mm), with excellent post-surgical survival regardless of whether surgery is early- or under-surveillance. Appropriate guideline implementation for surgical thresholds and interval clinical follow-up could have prevented most AoD events. Valvular disease guideline should also be followed to prevent AoD and improve survival in these patients.

Funding Acknowledgement

Type of funding sources: None.

Regadenoson stress echocardiography: a road ahead

Funding Acknowledgements

Type of funding sources: None.

Introduction

Drugs use in stress echocardiography (SE) have important limitations due to side effect and contraindications. Regadenoson (R) is emerging as a selective coronary vasodilator for pharmacological stress tests. Several studies have analyzed its diagnostic accuracy, but its prognostic value has not yet been studied.

Purpose

The objective is to assess safety and short-medium term prognosis in patients (p) who underwent SE with R.

Methods

Retrospective observational study. 126 patients were included from 2017 to 2020 and SE to study the detection of myocardial ischemia with R were performed. A positive SE test were consider if presented at least one of the follow: segmental changes in myocardial contractility, electrocardiography ischaemic changes or ischaemic symtomps. Adverse events (AE) were collected. To assess prognosis, we evaluated cardiovascular events (CV) with a median follow-up of 23 months, considering heart failure, angina, myocardial infarction (AMI) o cardiovascular death. We compare negative result SE test group (NG) with group of positive results (PG).

Results

Sixteen (13%) patients, presented AE, generally mild, with nausea in 4 patients. Two patients (1.6%) required the use of aminophylline for severe AE type bronchospasm.

Nineteen studies (15%) were positive: 17 (89%) showed echocardiographically positive results, 5 of them also had clinical or electrocardiographic positivity, one (5%) was considered positive only by electrocardiographic criteria and another by clinical criteria.

 There were no CV deaths at follow-up. In the NG, 6 events were observed versus 2 in the PG (6 vs 11%). Time to event of the NG was a median of 90 [3-600] days versus 110 [40-180] days in the PG. The most frequent event was HF (4 NG vs 1 PG), coronary angiography was performed in only 2 patients with HF of the NG and did not show significant lesions. In the NG there were 2 IAM (2 vs 0), one had severe stenosis in the right coronary artery and the other several moderate diffuse stenosis. There was no events for angina in the NG (0 vs 1). The annual cumulative incidence was 11% in the PG compared to 4% in the NG.

Conclusions

Stress echocardiography with regadenoson is a safe test with a low serious adverse events rate. As concern as prognosis, In our sample, NG presented a lower proportion of events with a lower annual cumulative incidence than PG and also in a 23-month follow-up. Abstract Figure.

P1821Proximal aorta longitudinal but not circumferential strain predicts aortic events and aortic root dilation rate in marfan syndrome patients

Background

The most common cardiovascular complications in Marfan syndrome (MFS) are aortic root dilation and type A aortic dissections. Elective aortic root surgery is indicated when maximum aortic diameter is larger than a defined threshold or in the case of fast-progressing dilation. However, maximum aortic diameter is limited for the prediction of aortic events. Indeed, a large international registry of acute aortic syndromes reported that as much as 40% of aortic dissections happen with maximum aortic diameter lower than 50 mm. Consequently, there is a need for new, non-invasive biomarkers to improve the prediction of aortic complications.

Purpose

The aim of the present study was to assess if proximal aorta circumferential and longitudinal strain and ascending aorta distensibility were associated with progressive aortic dilation and incidence of aortic events in Marfan syndrome patients.

Methods

Eighty seven Marfan syndrome patients free from previous cardiac/aortic surgery or dissection, were prospectively included in a multicenter follow-up. Patients were diagnosed by original Ghent criteria. Proximal aorta longitudinal and circumferential strain and distensibility were computed from baseline cine CMR images by means of feature-tracking. The predictive capacity of each stiffness biomarkers was separately tested with multivariable linear regression analysis (aortic growth) and with Cox logistic regression analysis (aortic events), both corrected for clinical and demographic variables, including baseline maximum aortic diameter.

Results

During a follow-up of 81.6±17 months, mean diameter growth-rate was 0.65±0.67 mm/year and z-score growth rate was 0.07±0.13 / year. Elective aortic root replacement was performed in 11 patients while two patients presented type A aortic dissection.Baseline proximal aorta longitudinal strain was independently related to diameter growth-rate (p=0.001), z-score growth-rate (p=0.018) and aortic events (p=0.018). Conversely, neither circumferential strain nor distensibility were independent predictors of diameter growth-rate (p=0.385 and p=0.381, respectively), z-score growth-rate (p=0.515 and p=0.484, respectively) and aortic events (p=0.064 and p=0.205, respectively).

Conclusions

Proximal aorta longitudinal strain predicts aortic root dilation and major aortic events in Marfan syndrome patients beyond aortic root diameter and clinical and demographic characteristics.

Acknowledgement/Funding

ISCIII PI14/0106, La Maratό de TV3 (20151330) and CIBERCV. Guala A. FP7/People n° 267128

P3373Predictors of dilatation of ascending aorta in patients with bicuspid aortic valve, a longitudinal multicenter study

Introduction

The bicuspid aortic valve (BAV) is frequently associated to dilation of the ascending aorta. Some cross-sectional studies have related the aortic dilation with morphotype and valvular dysfunction. The aim of this longitudinal multicenter study was to analyze the progression of the aortic dilation and to identify its predictors.

Methods

We included 459 patients (mean age 52±17; 325 men 70.8%) with BAV, without aortic coarctation. The BAV morphotype, significant valvular dysfunction and dilation of the aortic root and ascending aorta were established by echocardiography. The patients were followed annually, with an average of 7.5±3.2 years.

Results

77% of the patients had BAV with a fusion between left and right cusps, 21% between right and non coronary cusps and 2% between left and non coronary cusps, with a raphe in 77% of these patients. Risk factors included: 35% hypertension, 20% smoking, 5% diabetes and 18% dyslipidemia. The baseline study showed a maximum root diameter of 36±6.2 mm and ascending aorta of 39±8.1 mm. In 7% the aortic root was>45 mm, while in 32% the ascending aorta>45 mm. There was no valvular dysfunction in 17% of patients, while the 8% had significant aortic stenosis and 35% significant aortic regurgitation. The annual growth of the aortic root was 0.33±0.2 mm and for the ascending aorta was 0.38±0.3 mm. At the end of follow-up, 16% of the patients had a root>45 mm and 41% an ascending aorta>45 mm. The annual progression of aortic diameters was not related to valvular morphotype, valvular dysfunction or cardiovascular risk factors. The univariate analysis showed a significant relationship between the annual growth of the aortic root and arterial hypertension (p=0.028) and the annual growth of the ascending aorta with the male sex (p=0.019), smoking (p=0.046) and significant (moderate or severe) aortic stenosis (p=0.013). Diabetes mellitus and the presence of raphe were found to be slightly protective (p=0.049 and p=0.031, respectively). In the multivariate analysis, only the male sex and significant aortic stenosis were independent predictors of dilation of the ascending aorta.

Conclusions

In patients with bicuspid aortic valve, the progression of the dilation of the aortic root is related to hypertension and the growth of the ascending aorta with the male sex and the presence of significant aortic stenosis. Both bicuspid valve morphotype, basal aortic diameter or age were not related to the progression of aortic dilation.

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

OBJECTIVE

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

RESEARCH DESIGN AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Clinical perspectives into the use of thalidomide for central nervous system tuberculosis

BACKGROUND AND PURPOSE

Central nervous system (CNS) tuberculosis (TB) accounts for over 4% of all TB notifications in the UK and causes death or significant disability in over half of those affected. Tumour necrosis factor alpha is a critical cytokine involved in the neuropathogenesis of CNS TB. Thalidomide has been trialled in CNS TB due to its immunomodulatory and immune reconstitution effects through the inhibition of tumour necrosis factor alpha. Despite animal models demonstrating dramatic improvement in survival, studies in paediatric patients have been associated with higher levels of mortality. The effects of thalidomide have not yet been studied in adults with CNS TB. This narrative case series guides clinicians through a range of CNS TB clinical cases seen in a large London teaching hospital, serving a region with a high incidence of TB (32 per 100 000) with 55% of TB cases manifesting as extrapulmonary disease. We aimed to illustrate our experiences of using thalidomide to treat a range of severe CNS TB complications.

METHODS

Five inpatients at The Royal London Hospital, London, UK treated with thalidomide in addition to standard TB treatment are described in detail. The rationale for treatment initiation with thalidomide is explained.

RESULTS

The case examples are used to guide our reflections and lessons learnt regarding the use of thalidomide. Responses to treatment and functional outcomes suggest that thalidomide may be a useful adjunct to standard TB therapy in selected adult cases.

CONCLUSIONS

The experience gained from using thalidomide in this small case series may provide evidence leading to more research into using thalidomide to treat severe CNS TB.

Interleukin-17A and vascular remodelling in severe asthma; lack of evidence for a direct role

BACKGROUND

Bronchial vascular remodelling may contribute to the severity of airway narrowing through mucosal congestion. Interleukin (IL)-17A is associated with the most severe asthmatic phenotype but whether it might contribute to vascular remodelling is uncertain.

OBJECTIVE

To assess vascular remodelling in severe asthma and whether IL-17A directly or indirectly may cause endothelial cell activation and angiogenesis.

METHODS

Bronchial vascularization was quantified in asthmatic subjects, COPD and healthy subjects together with the number of IL-17A⁺ cells as well as the concentration of angiogenic factors in the sputum. The effect of IL-17A on in vitro angiogenesis, cell migration and endothelial permeability was assessed directly on primary human lung microvascular endothelial cells (HMVEC-L) or indirectly with conditioned medium derived from normal bronchial epithelial cells (NHBEC), fibroblasts (NHBF) and airway smooth muscle cells (ASMC) after IL-17A stimulation.

RESULTS

Severe asthmatics have increased vascularity compared to the other groups, which correlates positively with the concentrations of angiogenic factors in sputum. Interestingly, we demonstrated that increased bronchial vascularity correlates positively with the number of subepithelial IL-17A⁺ cells. However IL-17A had no direct effect on HMVEC-L function but it enhanced endothelial tube formation and cell migration through the production of angiogenic factors by NHBE and ASMC.

CONCLUSIONS & CLINICAL RELEVANCE

Our results shed light on the role of IL-17A in vascular remodelling, most likely through stimulating the synthesis of other angiogenic factors. Knowledge of these pathways may aid in the identification of new therapeutic targets.

Abstract P1-08-02: Breast tumor-specific MHC-II expression drives a unique pattern of adaptive resistance to antitumor immunity through MHC-II receptor checkpoint engagement

Background: We have previously shown that some breast cancers express major histocompatibility complex II (MHC-II), correlating with enhanced immune infiltration. In other tumor types, we have shown that MHC-II expression on tumor cells predicts clinical response to checkpoint inhibition. We sought to determine the direct effects of MHC-II on anti-tumor immunity and characterize mechanisms of immune escape in this breast cancer subset.

Methods: To determine the functional effects of MHC-II on tumor cells, we generated isogenic mouse breast tumor cells with enforced MHC-II expression and determined their ability to generate tumors in syngeneic mice, the impact on immunity, and their response to checkpoint inhibition. In a series of molecularly-characterized HER2+ (n=8) and triple-negative breast cancers (TNBC; n=103), we performed immunohistochemistry (IHC) and quantitative immunofluorescence (QIF) for Lag-3, PD-L1, CD4, CD8, FCRL6, and granzyme B.

Results: Following injection in syngeneic immunocompetent mice, MHC-II+ mouse breast tumors were more frequently rejected (p=0.04) and recruited greater numbers of CD4+ TILs. When MHC-II+ tumors escaped rejection, they expressed higher degrees of PD-1 and Lag-3 in the tumor and in the draining lymph node. Since Lag-3 is a checkpoint that specifically targets MHC-II, we hypothesized that MHC-II+ breast cancers escape anti-tumor immunity through suppressing MHC-II-mediated antigen presentation. Combinations of anti-Lag-3 and anti-Pd-1 antibodies inhibited growth of MHC-II+ tumors. These findings led us to also explore Fc receptor-like 6 (FCRL6), a previously reported MHC-II receptor expressed on NK and cytotoxic T cells. Residual MHC-II+ TNBC post-neoadjuvant chemotherapy (NAC) recruited greater numbers of CD4+ and CD8+ TILs (p=0.0001 and p=0.0002), suggesting enhanced immune recognition. However, MHC-II+ TNBCs also demonstrated a greater frequency of Lag-3+ and FCRL6+ TILs (p&lt;0.001 and p=0.01, respectively) which frequently co-occurred (p=0.003). Thus, our data suggest that MHC-II expression in breast tumors supports recruitment of MHC-II-specific checkpoint-positive TILs. In line with this concept, QIF analysis demonstrated that the presence of Lag3+ and/or FCRL6+ TILs was strongly associated with suppression of T cell cytotoxicity as assessed by granzyme-B+ CD8+ T cells (p=0.0001 and p=0.002, respectively). Functional analyses of FCRL6 on human NK cell lines and peripheral blood mononuclear cells (PBMCs) demonstrated that like Lag3, FCRL6 is a checkpoint which engages MHC-II and suppresses cytotoxic NK and T cell activity.

Conclusions: These data suggest that MHC-II+ breast tumors are immunologically active and circumvent anti-tumor immunity by targeting MHC-II antigen presentation through recruitment of Lag-3+ and FCRL6+ TILs. We describe herein FCRL6 as a novel bona fide immune checkpoint which targets MHC-II, which may impact a variety of cancers. MHC-II expression status may be a useful biomarker for patient stratification on anti-PD-1/anti-Lag-3 combination, and eventually, anti-PD-1/anti-FCRL6 combinations in patients with breast cancer.

Citation Format: Balko JM, Johnson DB, Ericsson-Gonzalez P, Nixon MJ, Salgado R, Sanchez V, Shreeder DM, Rimm DL, Loi S, Kim JY, Bordeaux J, Sanders ME, Davis RS. Breast tumor-specific MHC-II expression drives a unique pattern of adaptive resistance to antitumor immunity through MHC-II receptor checkpoint engagement [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-08-02.

A Health Services Research Agenda for Bariatric Surgery Within the Veterans Health Administration

In 2016, the Veterans Health Administration (VHA) held a Weight Management State of the Art conference to identify evidence gaps and develop a research agenda for population-based weight management for veterans. Included were behavioral, pharmacologic, and bariatric surgery workgroups. This article summarizes the bariatric surgery workgroup (BSWG) findings and recommendations for future research. The BSWG agreed that there is evidence from randomized trials and large observational studies suggesting that bariatric surgery is superior to medical therapy for short- and intermediate-term remission of type 2 diabetes, long-term weight loss, and long-term survival. Priority evidence gaps include long-term comorbidity remission, mental health, substance abuse, and health care costs. Evidence of the role of endoscopic weight loss options is also lacking. The BSWG also noted the limited evidence regarding optimal timing for bariatric surgery referral, barriers to bariatric surgery itself, and management of high-risk bariatric surgery patients. Clinical trials of pre- and post-surgery interventions may help to optimize patient outcomes. A registry of overweight and obese veterans and a workforce assessment to determine the VHA's capacity to increase bariatric surgery access were recommended. These will help inform policy modifications and focus the research agenda to improve the ability of the VHA to deliver population-based weight management.

Abstract P6-10-02: MHC-II positive breast tumors are more immunogenic and may preferentially select for LAG-3-positive tumor immune infiltrates

Background: Lymphocyte-activation gene 3 (LAG-3) is a T-cell checkpoint regulator and a current target in immunotherapy trials. LAG-3's main ligand is MHC class II (MHC-II), to which it binds with higher affinity than CD4. Binding of LAG3 to MHC-II antigen-presenting cells negatively regulates cellular proliferation, activation, and homeostasis of T cells, similarly to CTLA-4 and PD-1, suggesting that antibodies targeting LAG-3 may demonstrate similar anti-tumor immune effects.

Hypothesis: We recently reported an association of MHC-II on tumor cells and its involvement in mediating sensitivity to PD-1/PD-L1 monoclonal antibodies. MHC-II demonstrates a strong bimodal expression pattern on tumor cells from a variety of tissues, including those of the breast. In breast cancer patients, tumor-specific MHC-II expression on TNBCs is correlated with a 'hot' immune environment. We hypothesized that 1) MHC-II expression may drive potent anti-tumor immune responses and 2) MHC-II-positive tumors that generate immunotolerance may develop a specific immune checkpoint dependency on LAG-3, since LAG-3 is the inhibitory receptor for MHC-II-mediated antigen presentation.

Methods: To determine the functionality of MHC-II in driving anti-tumor immune responses, we constitutively expressed the MHC-II master regulator CIITA in MMTV-neu mouse tumor cells and determined their ability to form tumors in immunocompetent syngeneic hosts. To evaluate the association of MHC-II+ tumors with LAG-3 expression, we evaluated LAG-3-positivity by immunohistochemistry (IHC) in lymphocytic infiltrates in a series of 111 post-NAC TNBC specimens from patients with residual disease remaining after presurgical chemotherapy. Tumor-infiltrating lymphocytes (TILs) were scored by H&E, PD-L1 and MHC-II (HLA-DR) were scored in the stroma and tumor compartments using automated quantitative immunofluorescence (AQUA).

Results: Enforced expression of MHC-II via constitutive expression of CIITA caused rejection in 60% of mice, while only 11% of mice rejected MMTV-neu tumors expressing the vector control (Fisher's exact p=0.04). All rejecting mice were immune to rechallenge with parental (non-CIITA-expressing) MMTV-neu cells, suggesting a memory effector response.

Clinically, 11/102 patients (10.8%) had LAG-3+ immune cells in their tumor. LAG-3+ tumors were strongly correlated with MHC-II positivity in tumor cells (p&lt;0.0001). Presence of LAG-3+ cells also correlated strongly with overall TILs (p&lt;0.0001), and PD-L1 expression on TILs (p&lt;0.02). Since the likelihood of identifying LAG3+ lymphocytes is confounded by the inclusion of poorly-infiltrated tumors, we performed a subset analysis on only those tumors with substantial TILs (&gt;20%). When this subset was analyzed, LAG-3 positivity retained its association with tumor MHC-II expression (p=0.0001), while the association of LAG-3 with stromal PD-L1 was reduced below the level of significance (p=0.052).

Conclusions: MHC-II expression causes increased immune activation in breast cancers, consistent with our previous findings. MHC-II positivity in breast tumors may identify a population with preferential dependence on the LAG-3 checkpoint, which may be important for future immunotherapy trials.

Citation Format: Balko JM, Loi S, Giltnane JM, Combs S, Estrada MV, Sanchez V, Rimm D, Sanders ME, Salgado R, Gomez H, Johnson DB. MHC-II positive breast tumors are more immunogenic and may preferentially select for LAG-3-positive tumor immune infiltrates [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 P6-10-02.

KIT multi-physics tools for the analysis of design and beyond design basis accidents of light water reactors

This paper describes the KIT numerical simulation tools under extension and validation for the analysis of design and beyond design basis accidents (DBA) of Light Water Reactors (LWR). The description of the complex thermal hydraulic, neutron kinetics and chemo-physical phenomena going on during off-normal conditions requires the development of multi-physics and multi-scale simulations tools which are fostered by the rapid increase in computer power nowadays. The KIT numerical tools for DBA and beyond DBA are validated using experimental data of KIT or from abroad. The developments, extensions, coupling approaches and validation work performed at KIT are shortly outlined and discussed in this paper.

UVB irradiation as a tool to assess ROS-induced damage in human spermatozoa

One of the consequences of oxygen metabolism is the production of reactive oxygen species (ROS) which in a situation of imbalance with antioxidants can damage several biomolecules, compromise cell function and even lead to cellular death. The particularities of the sperm cell make it particularly vulnerable to ROS attack compromising its functionality, mirrored in terms of fertility outcome and making the study of the origin of sperm ROS, as well as the alterations they cause very important. In the present work, we used UVB irradiation, an easy experimental approach known as a potent inducer of ROS formation, to better understand the origin of ROS damage without any confounding effects that usually exist in disease models in which ROS are reported to play a role. To address these issues we evaluated sperm mitochondrial ROS production using the Mitosox Red Probe, mitochondrial membrane potential using the JC-1 probe, lipid peroxidation through BODIPY probe and vitality using PI. We observed that UVB irradiation leads to an increase in sperm mitochondrial ROS production and lipid peroxidation that occur previously to an observable mitochondrial dysfunction. We concluded that sperm UVB irradiation appears to be a good and easily manipulated in vitro model system to study mitochondria-induced oxidative stress in spermatozoa and its consequences, which may be relevant in terms of dissecting the action pathways of many other pathologies, drugs and contaminants, including endocrine disruptors.

Development of multi-physics code systems based on the reactor dynamics code DYN3D

The reactor dynamics code DYN3D has been coupled with the CFD code ANSYS CFX and the 3D thermal hydraulic core model FLICA4. In the coupling with ANSYS CFX, DYN3D calculates the neutron kinetics and the fuel behavior including the heat transfer to the coolant. The physical data interface between the codes is the volumetric heat release rate into the coolant. In the coupling with FLICA4 only the neutron kinetics module of DYN3D is used. Fluid dynamics and related transport phenomena in the reactor's coolant and fuel behavior is calculated by FLICA4.

The correctness of the coupling of DYN3D with both thermal hydraulic codes was verified by the calculation of different test problems. These test problems were set-up in such a way that comparison with the DYN3D stand-alone code was possible. This included steady-state and transient calculations of a mini-core consisting of nine real-size PWR fuel assemblies with ANSYS CFX/DYN3D as well as mini-core and a full core steady-state calculation using FLICA4/DYN3D.

Oxidative stress in immunocompetent patients with severe community-acquired pneumonia. A pilot study

OBJECTIVE

A comparison was made of the oxidative stress (OS) levels of patients with either viral or bacterial severe community-acquired pneumonia (sCAP) and of patients without infection (healthy volunteers (HV) and patients with acute myocardial infarction (AMI)).

DESIGN

A prospective observational study was made.

PATIENTS

Critically ill patients with sCAP.

VARIABLES

The TBARS level was measured as an index of oxidative injury. SOD, CAT and redox glutathione system (GSH, GSSG, GR, GPx) activities were measured as reflecting antioxidant capacity. Severity of illness was assessed by the APACHE II, SOFA and SIRS scores.

RESULTS

Thirty-seven subjects were included: 15 patients with CAP (12 of bacterial origin [BCAP] and 3 due to 2009 A/H1N1 virus [VCAP]), 10 HV and 12 AMI patients. Intensive care CAP mortality was 26.7% (n=4). Plasmatic TBARS levels were higher in CAP patients than in HV, but similar to those recorded in AMI patients. In contrast, VCAP was associated with lower TBARS levels, and some components of the glutathione redox system were higher in BCAP patients and HV. The OS levels did not differ between survivors and non-survivors.

CONCLUSION

Our results suggest the occurrence of higher OS in sCAP patients compared with HV. In contrast, lower TBARS levels were observed in VCAP patients, suggesting an increase of antioxidant activity related to the redox glutathione system. However, further research involving a larger cohort is needed in order to confirm these findings.

Joint source/channel coding for prioritized wireless transmission of multiple 3-D regions of interest in 3-D medical imaging data

This paper presents a 3-D medical image coding method featuring two major improvements to previous work on 3-D region of interest (RoI) coding for telemedicine applications. Namely, 1) a data prioritization scheme that allows coding of multiple 3-D-RoIs; and 2) a joint/source channel coding scheme that allows prioritized transmission of multiple 3-D-RoIs over wireless channels. The method, which is based on the 3-D integer wavelet transform and embedded block coding with optimized truncation with 3-D context modeling, generates scalable and error-resilient bit streams with 3-D-RoI decoding capabilities. Coding of multiple 3-D-RoIs is attained by prioritizing the wavelet-transformed data according to a Gaussian mixed distribution, whereas error resiliency is attained by employing the error correction capabilities of rate-compatible punctured turbo codes. The robustness of the proposed method is evaluated for transmission of real 3-D medical images over Rayleigh-fading channels with a priori knowledge of the channel condition. Evaluation results show that the proposed coding method provides a superior performance compared to equal error protection and unequal error protection techniques.

Anesthesia-induced developmental neurodegeneration: the role of neuronal organelles

Exposure to general anesthetics (GAs) and antiepileptics during critical stages of brain development causes significant neurotoxicity to immature neurons. Many animal, and emerging human studies have shown long-term functional sequelae manifested as behavioral deficits and cognitive impairments. Since GAs and antiepileptic drugs are a necessity, current research is focused on deciphering the mechanisms responsible for anesthesia-induced developmental neurotoxicity so that protective strategies can be devised. These agents promote massive and wide-spread neuroapoptosis that is caused by the impairment of integrity and function of neuronal organelles. Mitochondria and endoplasmic reticulum are particularly vulnerable. By promoting significant release of intracellular calcium from the endoplasmic reticulum, anesthetics cause an increase in mitochondrial calcium load resulting in the loss of their integrity, release of pro-apoptotic factors, functional impairment of ATP synthesis, and enhanced accumulation of reactive oxygen species. The possibility that GAs may have direct damaging effects on mitochondria, resulting in the impairment of their morphogenesis, also has been proposed. This review will present evidence that neuronal organelles are critical and early targets of anesthesia-induced developmental neurotoxicity.

Human cytomegalovirus infection of THP-1 derived macrophages reveals strain-specific regulation of actin dynamics

Human cytomegalovirus (HCMV) remains latent in cells of the myeloid lineage after primary infection. The THP-1 monocytic cell line is conditionally permissive for infection and has been used primarily to study the process of HCMV reactivation when the cells are induced to differentiate. In the present report, we characterized lytic infection in THP-1 derived macrophages using two strains of HCMV, Towne and BAC-derived TR. Our findings indicate that these cells express viral genes of all three kinetic classes and produce extracellular virus, but that there is a delay in these processes relative to productively infected fibroblasts. Importantly, our studies in THP-1 derived macrophages revealed strain-specific differences in pp65 trafficking and actin dynamics. Based on these observations, our studies indicate that differentiated THP-1 cells can serve as a valuable model for lytic infection.

EphA3 expressed in the chicken tectum stimulates nasal retinal ganglion cell axon growth and is required for retinotectal topographic map formation

Background

Retinotopic projection onto the tectum/colliculus constitutes the most studied model of topographic mapping and Eph receptors and their ligands, the ephrins, are the best characterized molecular system involved in this process. Ephrin-As, expressed in an increasing rostro-caudal gradient in the tectum/colliculus, repel temporal retinal ganglion cell (RGC) axons from the caudal tectum and inhibit their branching posterior to their termination zones. However, there are conflicting data regarding the nature of the second force that guides nasal axons to invade and branch only in the caudal tectum/colliculus. The predominant model postulates that this second force is produced by a decreasing rostro-caudal gradient of EphA7 which repels nasal optic fibers and prevents their branching in the rostral tectum/colliculus. However, as optic fibers invade the tectum/colliculus growing throughout this gradient, this model cannot explain how the axons grow throughout this repellent molecule.

Methodology/Principal Findings

By using chicken retinal cultures we showed that EphA3 ectodomain stimulates nasal RGC axon growth in a concentration dependent way. Moreover, we showed that nasal axons choose growing on EphA3-expressing cells and that EphA3 diminishes the density of interstitial filopodia in nasal RGC axons. Accordingly, in vivo EphA3 ectodomain misexpression directs nasal optic fibers toward the caudal tectum preventing their branching in the rostral tectum.

Conclusions

We demonstrated in vitro and in vivo that EphA3 ectodomain (which is expressed in a decreasing rostro-caudal gradient in the tectum) is necessary for topographic mapping by stimulating the nasal axon growth toward the caudal tectum and inhibiting their branching in the rostral tectum. Furthermore, the ability of EphA3 of stimulating axon growth allows understanding how optic fibers invade the tectum growing throughout this molecular gradient. Therefore, opposing tectal gradients of repellent ephrin-As and of axon growth stimulating EphA3 complement each other to map optic fibers along the rostro-caudal tectal axis.

P1-07-19: Analysis of HER2−Status in Breast Cancer by Mass Spectrometry in Archival, Formalin-Fixed Tissues

HER2 (ERBB2) is overexpressed in about 25% of breast cancers and predicts clinical benefit from trastuzumab, as well as response to anthracycline-based chemotherapy. Fluorescence in situ hybridization (FISH) to detect HER2 gene copy number and immunohistochemistry (IHC) to detect HER2 protein levels are approved by the FDA to identify HER2−positive (H2) tumors. However, the 2007 ASCO/CAP report concluded that approximately 20% of HER2 testing may be inaccurate. Further, the available data did not clearly demonstrate clear superiority of either IHC or FISH as a predictor of benefit from anti-HER2 therapy. Discordance between these methods is as high as 5%. Thus, novel complementary quantitative methods for interrogating HER2 expression in tumors are needed.

Targeted protein analysis by multiple reaction monitoring mass spectrometry (MRM-MS) offers a powerful approach to configure assays for specific proteins without using antibodies. Our studies using this platform have demonstrated applicability to formalin-fixed, paraffin-embedded (FFPE) specimens. In the current studies, we used this approach to measure signals from two tryptic peptides specific to HER2, one each from the extracellular and intracellular domains, selected from among 28 candidates based on their signal intensity and sharpness of their chromatographic profiles. Preliminary studies with a HER2−overexpressing BT474 xenograft in mice demonstrated quantitation and detected previously reported HER2 ectodomain shedding. Subsequent analysis of FFPE tissue from five H2 and five triple-negative (TN) tumors yielded measurement of at least 1 femptomole of receptor for H2 tumors and less than 0.2 femptomole of receptor for TN tumors per microgram of digest analyzed. If we assume 200 picograms of protein per cell, the results suggest 110,00 to 468,000 receptors per cell in the H2 tumors and only 2,000 to 14,000 receptors per cell in the TN tumors. Despite significant biological variability in receptor levels measured among the specimens of each type, a clear separation of the H2 and TN tumors was achieved based on the peptide quantitation. This preliminary study demonstrates the potential of MRM-MS in FFPE tissue to provide an alternate approach to IHC-based protein analysis. MRM-MS offers the potential for more, accurate and robust HER2 quantification in clinical breast cancer tissues. The next phase of this work will encompass a larger sample set, including tumors with equivocal and negative FISH and/or IHC test results. Correlation with response to anti-Her2 therapy will be performed in samples with available follow-up data.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-07-19.

The abolishment of anesthesia-induced cognitive impairment by timely protection of mitochondria in the developing rat brain: the importance of free oxygen radicals and mitochondrial integrity

Early exposure to general anesthesia (GA) causes developmental neuroapoptosis in the mammalian brain and long-term cognitive impairment. Recent evidence suggests that GA also causes functional and morphological impairment of the immature neuronal mitochondria. Injured mitochondria could be a significant source of reactive oxygen species (ROS), which, if not scavenged in timely fashion, may cause excessive lipid peroxidation and damage of cellular membranes. We examined whether early exposure to GA results in ROS upregulation and whether mitochondrial protection and ROS scavenging prevent GA-induced pathomorphological and behavioral impairments. We exposed 7-day-old rats to GA with or without either EUK-134, a synthetic ROS scavenger, or R(+) pramipexole (PPX), a synthetic aminobenzothiazol derivative that restores mitochondrial integrity. We found that GA causes extensive ROS upregulation and lipid peroxidation, as well as mitochondrial injury and neuronal loss in the subiculum. As compared to rats given only GA, those also given PPX or EUK-134 had significantly downregulated lipid peroxidation, preserved mitochondrial integrity, and significantly less neuronal loss. The subiculum is highly intertwined with the hippocampal CA1 region, anterior thalamic nuclei, and both entorhinal and cingulate cortices; hence, it is important in cognitive development. We found that PPX or EUK-134 co-treatment completely prevented GA-induced cognitive impairment. Because mitochondria are vulnerable to GA-induced developmental neurotoxicity, they could be an important therapeutic target for adjuvant therapy aimed at improving the safety of commonly used GAs.

Abstract P6-04-05: Digital Quantification of Post-Neoadjuvant Chemotherapy Breast Tumor RNA Reveals a Basal-Derived Gene Signature Associated with Post-Treatment Ki67

Neoadjuvant chemotherapy (NAC) leads to a pathological complete response (pCR) in -20% of patients with breast cancer. The rest of the patients exhibit residual disease (RD) in the breast after NAC and are more likely to have a metastatic recurrence. Recent data show that tumor cell proliferation, as measured by Ki67 in the residual post-NAC cancer, can inform clinical outcome. We hypothesized that RD after NAC will harbor different gene expression as a function of Ki67 index. A 2nd hypothesis is that identification of key alterations in tumors with post-NAC high Ki67 will identify molecules or networks that can be therapeutically targeted in the immediate post-operative setting to eradicate clinically silent micro-metastases.

We utilized Nanostring digital RNA quantification to measure the expression of 350 genes in 49 post-NAC residual breast cancers. The cohort was enriched for triple-negative cancers (24/49). Genes were selected based on relevance to breast cancer, published prognostic signatures, and our own unsupervised class discovery approach from existing microarray data. For the selected gene sets, we included a chemo-resistance signature (CHEMO), a stroma signature (STROMA), and a WNT/metastasis signature (WNT/MET). For the unsupervised analysis, publicly available pre-treatment microarray data from chemotherapy-treated ER-breastcancers that did not achieve pCR were clustered and the two most prominent groups were used to select a 250 gene set (CLUSTER). Ki67 was assessed in the RD for the 49 tumors and correlated to absolute RNA counts of the 350 selected genes.

Ki67 was strongly associated with subtype as defined by the PAM50 classifier (P&lt;0.0001). Basal tumors demonstrated the highest Ki67, followed by Luminal B, HER2, and Luminal A tumors (median = 63.5, 27, 22.6, and 5.5%, respectively). The CHEMO signature correlated inversely with Ki67 index (p=2.5e-8): paradoxically, genes positively associated with a higher probability of pCR correlated with a high Ki67 in the post-NAC specimens. Thus, chemotherapy-enriched tumors demonstrate distinct and unexpected gene expression patterns after treatment. The WNT/MET and STROMA gene sets showed significant trends with similar directionality to the CHEMO gene set. Our CLUSTER gene set was highly predictive of Ki67 (p=3.6e-6) and robustly associated with basal subtype (p=2.6e-13). MELK, an anti-apoptotic kinase involved in activation of Bcl-G was positively associated with a high Ki67 independently of tumor subtype (p=0.035 and p=0.045 in luminal and basal, respectively). In luminal tumors, high expression of BRCA1, BRCA2, and RRM2 was associated with high Ki67 (p=0.027, 0.016, and 7e-5, respectively), while reduced DUSP4 expression, a MAPK phosphatase, was predictive of high Ki67 in basal post-NAC tumors (p=6e-4).

Existing gene expression predictors built on pre-treatment data did not match expected patterns in chemotherapy-enriched tumors. Breast cancer subtype was strongly associated with a chemotherapy-refractory high Ki67 index in the surgically removed tumors. Further, the assessment of gene expression patterns in RD may be important in ascertaining the molecular underpinnings of aggressive disease. Thus, our defined gene signature may offer insights into molecular targets in patients who do not achieve pCR after NAC.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-04-05.

Role of cognitive reserve in progression from mild cognitive impairment to dementia

Cognitive reserve is the ability to optimize performance through differential recruitment of brain networks, which may reflect the use of alternative cognitive strategies.