Prenatal cortisol exposure impairs adrenal function but not glucose metabolism in adult sheep

Adverse environmental conditions before birth are known to programme adult metabolic and endocrine phenotypes in several species. However, whether increments in fetal cortisol concentrations of the magnitude commonly seen in these conditions can cause developmental programming remains unknown. Thus, this study investigated the outcome of physiological increases in fetal cortisol concentrations on glucose-insulin dynamics and pituitary-adrenal function in adult sheep. Compared with saline treatment, intravenous fetal cortisol infusion for 5 days in late gestation did not affect birthweight but increased lamb body weight at 1-2 weeks after birth. Adult glucose dynamics, insulin sensitivity and insulin secretion were unaffected by prenatal cortisol overexposure, assessed by glucose tolerance tests, hyperinsulinaemic-euglycaemic clamps and acute insulin administration. In contrast, prenatal cortisol infusion induced adrenal hypo-responsiveness in adulthood with significantly reduced cortisol responses to insulin-induced hypoglycaemia and exogenous adrenocorticotropic hormone (ACTH) administration relative to saline treatment. The area of adrenal cortex expressed as a percentage of the total cross-sectional area of the adult adrenal gland was also lower after prenatal cortisol than saline infusion. In adulthood, basal circulating ACTH but not cortisol concentrations were significantly higher in the cortisol than saline-treated group. The results show that cortisol overexposure before birth programmes pituitary-adrenal development with consequences for adult stress responses. Physiological variations in cortisol concentrations before birth may, therefore, have an important role in determining adult phenotypical diversity and adaptability to environmental challenges.

A new oral model of free fatty acid kinetics to assess lipolysis in subjects with and without type 2 diabetes

Assessing free fatty acids (FFAs) kinetics and the role of insulin and glucose on FFA lipolysis and disposal may improve our understanding of the pathogenesis of type 2 diabetes (T2D). Some models have been proposed to describe FFA kinetics during an intravenous glucose tolerance test and only one during an oral glucose tolerance test. Here, we propose a model of FFA kinetics during a meal tolerance test and use it to assess possible differences in postprandial lipolysis in individuals with type 2 diabetes (T2D) and individuals with obesity without type 2 diabetes (ND). We studied 18 obese ND and 16 T2D undergoing three meal tolerance tests (MTT) on three occasions (breakfast, lunch, and dinner). We used plasma glucose, insulin, and FFA concentrations collected at breakfast to test a battery of models and selected the best one based on physiological plausibility, ability to fit the data, precision of parameter estimates, and the Akaike parsimony criterion. The best model assumes that the postprandial suppression of FFA lipolysis is proportional to the above basal insulin, while FFA disposal is proportional to FFA concentration. It was used to compare FFA kinetics in ND and T2D along the day. The maximum lipolysis suppression occurred significantly earlier in ND than T2D (39 ± 6 min vs. 102 ± 13 min, 36 ± 4 min vs. 78 ± 11 min, and 38 ± 6 min vs. 84 ± 13 min, P < 0.01, at breakfast, lunch, and dinner, respectively), making lipolysis significantly lower in ND than T2D. This is mainly attributable to the lower insulin concentration in the second group. This novel FFA model allows to assess lipolysis and insulin antilipolytic effect in postprandial conditions.NEW & NOTEWORTHY In this study, we propose a new mathematical model able to quantify postprandial FFA kinetics and adipose tissue insulin sensitivity in both subjects with obesity without type 2 diabetes (ND) and subjects with type 2 diabetes (T2D). Results show that the slower postprandial suppression of lipolysis in T2D contributes to the higher free fatty acid (FFA) concentration that, in turn, may contribute to hyperglycemia.

Nonstructural protein 1 widespread RNA decay phenotype varies among coronaviruses

Extensive remodeling of host gene expression by nonstructural protein 1 (nsp1) of coronaviruses is a well-documented and conserved aspect of coronavirus-host takeover. Using comparative transcriptomics we investigated the diversity of transcriptional targets between various nsp1 proteins. Additionally, affinity purification followed by mass spectrometry was implemented to identify common interactors between the different nsp1 proteins. Although we detected widespread RNA destabilization, closely related nsp1 showed little similarities in clustering of targeted genes. We observed a partial overlap in transcriptional targeting between α-CoV 229E and MERS nsp1, which may suggest a common targeting mechanism, as MERS nsp1 preferentially targets nuclear transcripts. Our interactome data show great variability between nsp1 interactions, with 229E nsp1, the smallest nsp1 tested here, interacting with the most number of host proteins. Although nsp1 is a rather well-conserved protein with conserved functions across different coronaviruses, our data indicate that its precise effects on the host cell are virus specific.

889 Management of Paediatric Appendicitis During the First Wave of COVID-19: Comparison of Our Centre to National Practice

Aim

Our hospital took part in a multi-centre prospective cohort study “the CASCADE study” investigating the management and early outcomes of children with appendicitis in the UK and Ireland during the first wave of the COVID-19 pandemic (1). The aim of this study was to compare our local outcomes to those at a national level.

Method

This was a prospective cohort study with data collected from 01/04/2020 to 31/05/2020. Primary outcome was treatment strategy for appendicitis. Secondary outcomes were duration of symptoms, ultrasound findings, rate of simple vs perforated appendicitis and complications.

Results

Overall, only a minority (2/24 [8%]) were initially treated non-operatively, with both proceeding to appendicectomy due to pain. Remaining children (24/26 [92%]) were primarily treated with appendicectomy. All were performed laparoscopically with no conversions to open. Ultrasound was performed for most children (23/26 [88%]) which accurately identified appendicitis (22/23 [95%]) and negative appendicectomy rate of zero. Rates of complex appendicitis were not higher than expected (10/26 [38%]) but had a longer duration of symptoms (median 66.0h [IQR21.5] vs 30.0h [27.2], p = 0.008) and more complications (4 vs 1). Post-operative length of stay was significantly shorter for simple appendicitis than complicated (median 1.0d [IQR0.0] vs 4.0 [IQR2.8], p = 0.001).

Conclusions

Practice in our centre contrasts with the CASCADE study's National findings where 39% were treated non-operatively, only 48% of appendicectomies were performed laparoscopically, only 53% of children had diagnostic imaging and negative appendicectomy rate was 4.5%. Rates of complications for simple and complex appendicitis were similar, but post-operative length of stay shorter in our centre.

18 The Impact of Social Deprivation on TNM Staging of Non-Melanoma Skin Cancers: An Initial Review

Aim

Over 150,000 cases of non-melanoma skin cancer (NMSC) are diagnosed per year in the UK [1], with greatest incidence in less deprived socioeconomic groups [2]. The association between social deprivation and melanoma staging has been reported [3], however is not as well considered in Basal or Squamous Cell Carcinomas (BCCs/SCCs).

Method

A pilot review of 200 NMSC excision biopsies completed at a single hospital was undertaken. Specimens were identified via the histopathology database and included all excising specialities and anatomical locations. Registered postcodes were categorised into a decile via the English Indices of Deprivation 2019 database (1= most deprived, 10= least deprived). Tumour staging was identified from the histopathology report.

Results

200 specimens were reviewed including 9 deprivation deciles ranging from Decile 2 to Decile 10. Decile 6 was the most common decile, incorporating 20% of all specimens. pT1 BCCs were the most commonly excised lesion at 68.5%, pT3 BCCs and SCCs were least commonly excised (1.5% of specimens each). Increased proportions of pT2 BCCs and SCCs occurred in less deprived deciles, contrasting with pT3 BCCs which clustered in Deciles 6 and 7. pT3 SCCs comprised 11.1% of excised lesions in Decile 4, the greatest proportion outside of pT1 lesions.

Conclusions

This initial review suggests that the distribution of NMSC staging is not even across social deprivation levels. Increased proportions of pT2 staged lesions occurred in less deprived cohorts. Further expansion of the dataset is justified to assess the degree to which social deprivation may affect NMSC stage at excision.

The KSHV ORF20 Protein Interacts with the Viral Processivity Factor ORF59 and Promotes Viral Reactivation

Upon Kaposi's Sarcoma-associated herpesvirus (KSHV) lytic reactivation, rapid and widespread amplification of viral DNA (vDNA) triggers significant nuclear reorganization. As part of this striking shift in nuclear architecture, viral replication compartments are formed as sites of lytic vDNA production along with remarkable spatial remodeling and the relocalization of cellular and viral proteins. These viral replication compartments house several lytic gene products that coordinate viral gene expression, vDNA replication, and nucleocapsid assembly. The viral proteins and mechanisms that regulate this overhaul of the nuclear landscape during KSHV replication remain largely unknown. KSHV's ORF20 is a widely conserved lytic gene among all herpesviruses, suggesting it may have a fundamental contribution to the progression of herpesviral infection. Here, we utilized a promiscuous biotin ligase proximity labeling method to identify the proximal interactome of ORF20, which includes several replication-associated viral proteins, one of which is ORF59, the KSHV DNA processivity factor. Using coimmunoprecipitation and immunofluorescence assays, we confirmed the interaction between ORF20 and ORF59 and tracked the localization of both proteins to KSHV replication compartments. To further characterize the function of ORF20, we generated an ORF20-deficient KSHV and compared its replicative fitness to that of wild-type virus. Virion production was significantly diminished in the ORF20-deficient virus as observed by supernatant transfer assays. Additionally, we tied this defect in viable virion formation to a reduction in viral late gene expression. Lastly, we observed an overall reduction in vDNA replication in the ORF20-deficient virus, implying a key role for ORF20 in the regulation of lytic replication. Taken together, these results capture the essential role of KSHV ORF20 in progressing viral lytic infection by regulating vDNA replication alongside other crucial lytic proteins within KSHV replication compartments. IMPORTANCE Kaposi's Sarcoma-associated herpesvirus (KSHV) is a herpesvirus that induces lifelong infection, and as such, its lytic replication is carefully controlled to allow for efficient dissemination from its long-term reservoir and for the spread of the virus to new hosts. Viral DNA replication involves many host and viral proteins, coordinating both in time and space to successfully progress through the viral life cycle. Yet, this process is still not fully understood. We investigated the role of the poorly characterized viral protein ORF20, and through proximity labeling, we found that ORF20 interacts with ORF59 in replication compartments and affects DNA replication and subsequent steps of the late viral life cycle. Collectively, these results provide insights into the possible contribution of ORF20 to the complex lytic DNA replication process and suggest that this highly conserved protein may be an important modulator of this key viral mechanism.

Magnetic Nanoparticle and Exosomal Therapeutic (M-NEXT) Effects on HIV-Associated Neurotoxicity

The human immunodeficiency virus (HIV) envelope glycoprotein protein 120 (gp120) induces neurotoxicity associated with HIV-associated neurocognitive disorders (HAND). Mechanism of Gp120-mediated neurotoxicity is primarily apoptosis. Currently, there are no therapeutics that address gp120 neurotoxicity. A biocompatible, efficacious therapeutic that easily crosses the blood-brain barrier (BBB) is needed to treat neuronal toxicity observed in HIV-infected individuals. Magnetic nanoparticles (MNPs) have successfully delivered anti-HIV agents across in vitro BBB transwell model. However, MNPs at high doses may damage cells. Exosomal extracellular vesicles (xEVs) are endogenous nanocarriers capable of crossing the BBB. Unlike MNPs, xEVs interact with cells in a paracrine or juxtracrine manner, lacking long-range site specificity. Here we investigated the efficacy of an MNP and xEV-coupled therapeutic (M-NEXT) as a nanocarrier for targeted delivery of anti-HIV fusion agent across the BBB to inhibit HIV-gp120 associated neuropathology. M-NEXT consisting of MNPs encapsulated within xEV carrying T20 peptide on the surface was synthesized and characterized via zeta potential, dynamic light scattering, and TEM imaging. Preliminary efficacy studies using SH-SY5Y cocultured with the in vitro BBB model showed that the M-NEXT-T20-fusion peptide protected neurons from HIV gp120-mediated neurotoxicity. Additionally, BBB integrity and permeability assessed via trans-endothelial resistance (TEER) and a Dextran-FITC transport assay was unaffected. SH-SY5Y viability measured by XTT assay was not significantly modulated by M-NEXT. In summary, preliminary findings support M-NEXT as effective nanocarriers for delivery of anti-HIV gp120 associated neurotoxicity agents.

Implementing Digitalised Lean Manufacturing Training in a UK Engine Manufacturing Centre During the SARS-CoV2 Pandemic of 2020

This paper examines a novel way of training Lean Manufacturing Systems and Tools utilising an Industry 4.0 methodology during the SARS-COVID2 Pandemic of 2020. Currently, it is challenging for the Integrated Production Systems Team, responsible for carrying out training on the Lean principles, to undertake the training safely and without the risk of possible disease transmission. This is due to the usual close quarters training carried out in the Engine Manufacturing Centre. Schools, Colleges and Universities have adapted and utilised technology and moved to an Industry 4.0 digitalised approach to learning and development. This is therefore an opportunity for manufacturing to follow suit and create digitised solutions to training and development opportunities, to ensure that the employees within the manufacturing facility have adequate knowledge on the Lean principles.

Investigation and management of prosthetic joint infection in knee replacement: A BASK Surgical Practice Guideline

BACKGROUND

The burden of knee replacement prosthetic joint infection (KR PJI) is increasing. KR PJI is difficult to treat, outcomes can be poor and it is financially expensive and limited evidence is available to guide treatment decisions.

AIM

To provide guidelines for surgeons and units treating KR PJI.

METHODS

Guideline formation by consensus process undertaken by BASK's Revision Knee Working Group, supported by outputs from UK-PJI meetings.

RESULTS

Improved outcomes should be achieved through provision of care by revision centres in a network model. Treatment of KR PJI should only be undertaken at specialist units with the required infrastructure and a regular infection MDT. This document outlines practice guidelines for units providing a KR PJI service and sets out: CONCLUSIONS: KR PJI patients treated within the NHS should be provided the best care possible. This report sets out guidance and support for surgeons and units to achieve this.

Stealing the Show: KSHV Hijacks Host RNA Regulatory Pathways to Promote Infection

Kaposi's sarcoma-associated herpesvirus (KSHV) induces life-long infections and has evolved many ways to exert extensive control over its host's transcriptional and post-transcriptional machinery to gain better access to resources and dampened immune sensing. The hallmark of this takeover is how KSHV reshapes RNA fate both to control expression of its own gene but also that of its host. From the nucleus to the cytoplasm, control of RNA expression, localization, and decay is a process that is carefully tuned by a multitude of factors and that can adapt or react to rapid changes in the environment. Intriguingly, it appears that KSHV has found ways to co-opt each of these pathways for its own benefit. Here we provide a comprehensive review of recent work in this area and in particular recent advances on the post-transcriptional modifications front. Overall, this review highlights the myriad of ways KSHV uses to control RNA fate and gathers novel insights gained from the past decade of research at the interface of RNA biology and the field of KSHV research.

Fated for decay: RNA elements targeted by viral endonucleases

For over a decade, studies of messenger RNA regulation have revealed an unprecedented level of connectivity between the RNA pool and global gene expression. These connections are underpinned by a vast array of RNA elements that coordinate RNA-protein and RNA-RNA interactions, each directing mRNA fate from transcription to translation. Consequently, viruses have evolved an arsenal of strategies to target these RNA features and ultimately take control of the pathways they influence, and these strategies contribute to the global shutdown of the host gene expression machinery known as “Host Shutoff”. This takeover of the host cell is mechanistically orchestrated by a number of non-homologous virally encoded endoribonucleases. Recent large-scale screens estimate that over 70 % of the host transcriptome is decimated by the expression of these viral nucleases. While this takeover strategy seems extraordinarily well conserved, each viral endonuclease has evolved to target distinct mRNA elements. Herein, we will explore each of these RNA structures/sequence features that render messenger RNA susceptible or resistant to viral endonuclease cleavage. By further understanding these targeting and escape mechanisms we will continue to unravel untold depths of cellular RNA regulation that further underscores the integral relationship between RNA fate and the fate of the cell.

1059 Sleep Parameters In People With Type 2 Diabetes With And Without Insomnia Symptoms

Introduction

There is an increasing awareness of the high prevalence of insomnia symptoms in people with type 2 diabetes (T2D). Past studies have demonstrated the importance of measuring sleep parameters in both averages and variabilities using subjective and objective methods. Thus, we aimed to compare the averages and variability of sleep parameters in people with T2D with and without insomnia symptoms.

Methods

Actigraph measurements and sleep diaries were used in 59 participants to assess sleep parameters, including sleep efficiency (SE), sleep latency, total sleep time, and wake after sleep onset over seven nights. Validated instruments were used to assess the symptoms of depression, anxiety, and pain. Circular data were used to describe the distribution of bed distribution with SE as a magnitude for both groups. Mann Whitney U test was utilized to compare averages and variability of sleep parameters between the two groups. Multivariable general linear model to control for demographic and clinical variables. For the secondary aim, multiple linear regression tests were utilized to assess the association between averages and variability values for both groups.

Results

SE was found to be lower in average and higher in variability for participants with T2D and insomnia symptoms, than those with T2D only subjectively and objectively. SE variability was also the only sleep parameter higher in people with T2D and insomnia symptoms, with psychological symptoms potentially playing a role in this difference. We observed that people in T2D+Insomnia tend to go to bed earlier compared to the T2D only group based on objective measures, but no difference was observed between groups in subjective measures. The only significant relationship in both objective and subjective measures was between the averages and variability of SE.

Conclusion

Our findings suggest a discrepancy between subjective and objective measures in only average of total sleep time, as well as agreement in measures of variability in sleep parameters. Also, the relationship between averages and variabilities suggested the importance of improving SE to minimize its variability. Further research is warranted to investigate the complex relationship between sleep parameters and psychological factors in people with T2D and insomnia symptoms.

Support

None

Bioengineered Exosomal Extracellular Vesicles in Cancer Therapeutics

Liquid or blood-based biopsy is a less invasive and more efficient method in which to clinicians can identify diagnostic, prognostic, and therapeutic responsive biomarkers in cancer patients. Circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), RNAs, proteins, metabolites, and extracellular vesicles (EVs) are all potential biomarkers found in liquid biopsies. All nucleated cells including healthy, virally infected, and cancer cells release EVs. Since the early 1980s, evidence has mounted to support the pathophysiological role of EVs in cancer. Here we focus on the smallest of the EV, the exosome, and their clinical relevance as nanotherapeutics for cancers. Exosomes obtained from tumors have been reported to promote and/or facilitate malignancy of cancers especially in terms of metastatic potential. Exosomal EVs have also contributed to the development of therapeutic resistance. Recent studies demonstrate that intrinsic and bioengineered exosomes can serve as effective therapeutic agents that disrupt cancer progression. Here we review the current literature regarding the utilization of bioengineered exosomes for therapeutics to treat prevalent cancers such as melanoma, glioma, breast, pancreatic, hepatic, cervical, prostate, and colon cancers. Overall, studies reviewed show that bioengineered exosomes are effective and promising for targeted cancer therapy.

57 Non-targeted metabolomic profiles within the uterine milieu of porcine pregnancies containing populations of uniform or diverse spherical, ovoid, or tubular conceptuses during initiation of embryo elongation

Alterations in the signalling of critical molecular factors within the uterine milieu result in deficiencies in embryo elongation, leading directly to embryonic loss as well as delayed elongation. The objective of this study was to identify metabolites within the uterine environment from populations of uniform and diverse porcine conceptuses as they transition between spherical, ovoid, and tubular conceptuses during the initiation of embryo elongation. White crossbred gilts (n=38) were bred at standing oestrus (designated Day 0) and again 24h later and randomly assigned to collection group. At Day 9, 10, or 11 of gestation, reproductive tracts were collected immediately following harvest and flushed with 40mL of RPMI-1640 media. Conceptus morphologies were assessed from each pregnancy to assign to 1 of 5 treatment groups based on these morphologies: (1) uniform spherical (n=8); (2) diverse spherical and ovoid (n=8); (3) uniform ovoid (n=8); (4) diverse ovoid and tubular (n=8); and (5) uniform tubular (n=6). Subsequently uterine flushings from these pregnancies were submitted for non-targeted profiling by gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) techniques. Raw spectral data were processed using the XCMS package in R (R Foundation for Statistical Computing, Vienna, Austria) and features were clustered using RAMclustR. Unsupervised multivariate principal component analysis was performed in R using pcamethods package, and univariate ANOVA was performed in R with a Benjamini-Hochberg false discovery rate adjustment. Principal component analysis of the GC-MS and UPLC-MS data identified 153 and 104 metabolites, respectively. Of the identified metabolites, 51 and 71 metabolites from the GC-MS and UPLC-MS analysis, respectively, corresponded to known compounds. After false discovery rate adjustment of the GC-MS and UPLC-MS data, 38 and 59 metabolites from the GC-MS and UPLC-MS analysis, respectively, differed (P&lt;0.05) in uterine flushings from pregnancies for the 5 conceptus stages. Some metabolites were greater (P&lt;0.05) in abundance for uterine flushings containing earlier stage conceptuses (i.e. spherical) such as uric acid, tryptophan, 5-hydroxy-L-tryptophan, and L-tryosine. In contrast, some metabolites were greater (P&lt;0.05) in abundance for uterine flushings containing later stage conceptuses (i.e. tubular) such as creatinine, serine, isovaleryl-I-carnitine, and lauric diethaolamide. These data illustrate several putative metabolites that change within the uterine milieu as porcine embryos transition between spherical, ovoid, and tubular conceptuses. Funding was provided by USDA-NIFA-AFRI Grant no. 2017-67015-26456.

Real-time determination of enantiomeric and isomeric content using photoelectron elliptical dichroism

The fast and accurate analysis of chiral chemical mixtures is crucial for many applications but remains challenging. Here we use elliptically-polarized femtosecond laser pulses at high repetition rates to photoionize chiral molecules. The 3D photoelectron angular distribution produced provides molecular fingerprints, showing a strong forward-backward asymmetry which depends sensitively on the molecular structure and degree of ellipticity. Continuously scanning the laser ellipticity and analyzing the evolution of the rich, multi-dimensional molecular signatures allows us to observe real-time changes in the chemical and chiral content present with unprecedented speed and accuracy. We measure the enantiomeric excess of a compound with an accuracy of 0.4% in 10 min acquisition time, and follow the evolution of a mixture with an accuracy of 5% with a temporal resolution of 3 s. This method is even able to distinguish isomers, which cannot be easily distinguished by mass-spectrometry.

A systematic review and meta-analysis of premature mortality in bipolar affective disorder

OBJECTIVE

To review and complete meta-analysis of studies estimating standardised mortality ratios (SMRs) in bipolar affective disorder (BPAD) for all-cause and cause-specific mortalities.

METHOD

Cause-specific mortality was grouped into natural and unnatural causes. These subgroups were further divided into circulatory, respiratory, neoplastic and infectious causes, and suicide and other violent deaths. Summary SMRs were calculated using random-effects meta-analysis. Heterogeneity was examined via subgroup analysis and meta-regression.

RESULTS

Systematic searching found 31 studies meeting inclusion criteria. Summary SMR for all-cause mortality = 2.05 (95% CI 1.89-2.23), but heterogeneity was high (I(2) = 96.2%). This heterogeneity could not be accounted for by date of publication, cohort size, mid-decade of data collection, population type or geographical region. Unnatural death summary SMR = 7.42 (95% CI 6.43-8.55) and natural death = 1.64 (95% CI 1.47-1.83). Specifically, suicide SMR = 14.44 (95% CI 12.43-16.78), other violent death SMR = 3.68 (95% CI 2.77-4.90), deaths from circulatory disease = 1.73 (95% CI 1.54-1.94), respiratory disease = 2.92 (95% CI 2.00-4.23), infection = 2.25 (95% CI 1.70-3.00) and neoplasm = 1.14 (95% CI 1.10-1.21).

CONCLUSION

Despite considerable heterogeneity, all summary SMR estimates and a large majority of individual studies showed elevated mortality in BPAD compared to the general population. This was true for all causes of mortality studied.

Abstract P2-03-05: Relationship between 64Cu-DOTA-trastuzumab positron emission tomography uptake and assessment of HER2 by immunohistochemistry in women with advanced breast cancer

Background: We have utilized 64Cu-DOTA-trastuzumab with PET imaging to assess the in vivo expression of HER2 in women with advanced breast cancer. We have demonstrated that a preadministered dose of trastuzumab 45 mg prior to injection of 64Cu-DOTA-trastuzumab resulted in a 75% decrease in the hepatic uptake of Cu-64, resulting in improved image quality.

Methods: Patients with biopsy confirmation of recurrent disease located outside the breast and axilla considered for study. Complete staging workup included CT of the chest, abdomen, and pelvis, bone scintigraphy and 18F FDG PET. At least 1 non-hepatic site of metastasis that was &gt; 2 cm separate from the biopsy site was also required. HER2 status was assessed by both IHC and FISH. Index lesions were identified on CT imaging. After the first two patients, all patients received a cold dose of 45mg of trastuzumab immediately prior to 64Cu-DOTA-trastuzumab to decrease liver uptake. 64Cu-DOTA-trastuzumab PET imaging was performed at 24 and 48 hours. Uptake on 64Cu-DOTA-trastuzumab was correlated with HER2 status by IHC and FISH.

Results: Fifteen women have undergone 64Cu-DOTA-trastuzumab PET imaging and quantitative image analysis. 10 patients were HER2+ (7 IHC 3+, 3 IHC 2+/FISH+), 3 patients were IHC 2+/FISH-, and 2 patients were IHC 1+. Tumor uptake by 64Cu-DOTA-trastuzumab PET max SUV was higher in HER2+ positive than HER2- patients (1.9-fold higher on day1, p&lt;0.02, and 1.7-fold higher on day2, p&lt;0.05). However, the lowest max SUV was in a HER2+ patient (HER2 2+/FISH+), demonstrating considerable heterogeneity.

Conclusion: 64Cu-DOTA-trastuzumab PET correlates with HER2+ status. However, due to high within and between patient variability, 64Cu-DOTA-trastuzumab PET imaging could potentially enrich for HER2+ patients that respond to HER2-targeted therapy, and could also suggest some HER2- patients that may benefit from HER2-targeted therapy. This hypothesis needs to be further explored in patients undergoing HER2-targeted therapy. This work was supported by the Department of Defense grant # BC095002.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-03-05.

Abstract P2-05-10: 64Cu-DOTA-trastuzumab positron emission tomography imaging of HER2 in women with advanced breast cancer

Background: We propose to utilize64Cu-DOTA-trastuzumab with PET imaging to assess the in vivo expression of HER2 in women with advanced breast cancer. We hypothesized that the uptake of HER2 in normal tissues compromises the quality of radiographic images and that the pre-administration of trastuzumab prior to injection of64Cu-DOTA-trastuzumab would improve image quality. Two different doses of cold trastuzumab (5 mg and 50 mg) were tested. Once the dose of cold trastuzumab was established in women with documented HER2 positive metastatic disease, we initiated a second study of64Cu-DOTA-trastuzumab PET imaging in women whose cancers were HER2 1+ and 2+ by immunohistochemical staining.

Methods: Patients with biopsy confirmation of recurrent disease located outside the breast and axilla considered for study. Complete staging workup included CT of the chest, abdomen, and pelvis, bone scintigraphy and18F FDG PET. At lease 1 non-hepatic site of metastasis that was &gt; 2 cm separate from the biopsy site was also required. HER2 status was assessed by both IHC and FISH. In the first study all patients were required to have HER2 positive disease and could not have received anti-HER therapy for &gt; 2 months. Immediately prior to injection of64Cu-DOTA-trastuzumab, a cold dose of either 5 mg or 50 mg of trastuzumab was administered.64Cu-DOTA-trastuzumab PET imaging was performed at 24 and 48 hours.

Results: Eight women with HER2 positive metastatic breast cancer have undergone64Cu-DOTA-trastuzumab PET imaging: 2 received a pre-64Cu-DOTA-trastuzumab PET dose of 5 mg trastuzumab and 6 received 50 mg.64Cu-DOTA-trastuzumab PET effectively visualized and provided uptake measurements for presumably HER2+ metastatic lesions in bone, liver, lung and, to a lesser degree, lymph nodes. The 50 mg dose resulted in approximately 75% decrease in liver uptake of64Cu and improved the visualization of hepatic metastasis. We have initiated the second phase of the study utilizing the pre-administration of 50 mg trastuzumab in women with HER2 1+ and 2 + disease. To date we have imaged one patient.

Conclusion:64Cu-DOTA-trastuzumab PET imaging is feasible and image quality is improved with the pre-administration of 50 mg trastuzumab. Enrollment of women with IHC 1+ and 2+ disease continues. This work was supported by the Department of Defense grant # 1024511.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-05-10.