TEK is a novel prognostic marker for clear cell renal cell carcinoma

OBJECTIVE

Clear cell renal cell carcinoma (ccRCC) is the most common type of kidney cancer. However, effective therapeutics for ccRCC are lacking. Novel biomarkers could provide critical information when determining prognoses for patients with ccRCC. In this study, we sought to determine if the expression of receptor tyrosine kinase (TEK) could be a potential novel prognostic biomarker for ccRCC. TEK, originally identified as an endothelial cell-specific receptor, plays an important role in the modulation of vasculogenesis and remodeling. Altered TEK expression has been observed in tumor tissues (e.g., oral squamous cell carcinomas, leukemia) and breast, gastric and thyroid cancers. However, the role of TEK in ccRCC remains unknown.

PATIENTS AND METHODS

Differential TEK expression between non-metastatic (stage M0) and metastatic (stage M1) ccRCC patient cohorts was determined from The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC). Furthermore, TEK expression was assessed as a prognostic factor using the time-dependent area under the curve (AUC) of Uno's C-index, the AUC value of the receiver operating characteristics (ROC) at 5 years, Kaplan-Meier survival curves and multivariate analyses.

RESULTS

A Kaplan-Meier curve analysis revealed that the downregulation of TEK expression was associated with a poor prognosis for patients with ccRCC with good discrimination (p<0.0001 and p=0.0044 for the TGCA and ICGC cohorts, respectively). Analyses of C-indices and receiver operating characteristic AUC values further support this discriminative ability. Moreover, multivariate analyses showed the prognostic significance of TEK expression levels (p<0.001).

CONCLUSIONS

Although additional clinical investigations will be needed, our results suggest that TEK is a potential biomarker for ccRCC.

Magnesium-Dependent Promotion of H2O2 Production Increases Ecological Competitiveness of Oral Commensal Streptococci

The pyruvate oxidase (SpxB)-dependent production of H₂O₂ is widely distributed among oral commensal streptococci. Several studies confirmed the ability of H₂O₂ to antagonize susceptible oral bacterial species, including caries-associated Streptococcus mutans as well as several periodontal pathobionts. Here we report a potential mechanism to bolster oral commensal streptococcal H₂O₂ production by magnesium (Mg²⁺) supplementation. Magnesium is a cofactor for SpxB catalytic activity, and supplementation increases the production of H₂O₂ in vitro. We demonstrate that Mg²⁺ affects spxB transcription and SpxB abundance in Streptococcus sanguinis and Streptococcus gordonii. The competitiveness of low-passage commensal streptococcal clinical isolates is positively influenced in antagonism assays against S. mutans. In growth conditions normally selective for S. mutans, Mg²⁺ supplementation is able to increase the abundance of S. sanguinis in dual-species biofilms. Using an in vivo biophotonic imaging platform, we further demonstrate that dietary Mg²⁺ supplementation significantly improves S. gordonii oral colonization in mice. In summary, our results support a role for Mg²⁺ supplementation as a potential prebiotic to promote establishment of oral health-associated commensal streptococci.

SAT0247 PREDICTORS OF ADVERSE OUTCOMES IN DIFFUSE ALVEOLAR HEMORRHAGE OF IMMUNE AND NON-IMMUNE CAUSES: 12-YEAR EXPERIENCE FROM A UNIVERSITY HOSPITAL

Background:

Diffuse alveolar hemorrhage (DAH) is a rare, life-threatening condition that has either immune or non-immune etiologies1. DAH caused by capillaritis can be immune-mediated (IM-DAH), e.g. anti-neutrophil cytoplasmic antibody (ANCA) vasculitis and systemic lupus erythematosus, but DAH may also result from anticoagulation, heart failure, drugs or inhaled toxins. Since IM-DAH has specific therapies available, we hypothesized that patients with IM-DAH would have a better prognosis.

Objectives:

We did a retrospective analysis of all DAH cases seen at our university hospital in the last 12 years to investigate the predictors of adverse outcomes.

Methods:

Using Epic radiant and Agfa Radiology Information System databases, we queried electronic medical records of all patients admitted to our university between Jan 2007 to Jan 2019 who had the words “diffuse alveolar hemorrhage” in their chest x-ray report. We manually reviewed charts of all these patients to confirm true DAH. True DAH was defined as suspicion of DAH on chest x-ray plus inclusion of DAH on the discharge problem list. We did a detailed chart review of true DAH cases to extract information regarding demographics, baseline disease characteristics, physical/serology/imaging findings, treatment received, and outcomes. The outcomes of interest were death, intubation, shock, need for hemodialysis (HD), and red blood cell transfusions. We compared IM-DAH with non IM-DAH cases using descriptive statistics, t-test, and chi-squared tests. We used logistic regression models to assess the influence of baseline characteristics on outcomes. A p-value < 0.05 was considered statistically significant.

Results:

There were 88 cases of DAH (M:F 54:34, median age 57) fulfilling inclusion criteria (Table 1). The non-immune etiology was diagnosed in 63%, while 36% were IM-DAH (18% ANCA associated, 9% SLE, 2% decompensated heart failure, the rest were others). No clear etiology for DAH was found in 37.5% cases. Death within 90 days of onset of DAH occurred in 37.5%, 5.6% had recurrent DAH, and 56.8% had sustained remission. Non-IM DAH cases had worse outcomes such as death and were less likely to experience sustained remission (Chi-squared = 19.1, p < 0.001), though IM-DAH were more likely to receive HD (Chi-squared = 7.5, p-value 0.01). Presence of extrapulmonary findings (e.g. nephritis) was a risk factor for adverse outcome, and was statistically significantly correlated with the amount of blood products received, need for HD and likelihood of death, which did not reach statistical significance. Shock and intubation were associated with a higher likelihood of death (p = 0.02 and p = 0.001, respectively).

Table 1.

Comparison of Clinical Characteristics of Immune versus Non-Immune Cases of Diffuse Alveolar Hemorrhage

VariableImmune cases(N = 32)Non-immune cases(N = 56)Statistical comparisonAge (years)51.0955.91P = 0.196%Female43.835.7P = 0.510%presenting with hemoptysis8 (25%)14 (25%)P = 0.101%extrapulmonary findings20 (62.5%)1 (1.7%)P = 6.9*e-10pANCA positive16 (50%)2 (3.6%)P = 0.0004% on anticoagulation9.42.5P = 0.090Mean Creatinine2.381.89P = 0.507Mean hospital length of stay (days)16.6923.27P = 0.139Drop in Hemoglobin prior to DAH and day of DAH0.241.17P = 0.070%Bronchoscopy-confirmed DAH62.575.0P = 0694Mean units of blood transfused1.912.66P = 0.448%Need for hemodialysis37.512.5P = 0.010%Shock (any kind)21.932.1P = 0.338%Need for intubation43.862.5P = 0.122%Death within 90 days12.552.7P = 0.0009

Conclusion:

DAH, a life-threatening condition, has both immune and non-immune etiologies. Our 12-years, single-center, university hospital experience showed that IM-DAH has a better prognosis than non IM-DAH. Presence of extrapulmonary manifestations was associated with worse outcomes.

References:

[1]Moo Suk Park. Diffuse Alveolar Hemorrhage. Tuberc Respir Dis (Seoul). 2013 Apr; 74(4): 151–162.

[2]Nasser M, Cottin V. Alveolar Hemorrhage in Vasculitis (Primary and Secondary). Semin Respir Crit Care Med. 2018 Aug;39(4):482-493.

Disclosure of Interests:

Ambika Bhushan: None declared, Dongseok Choi: None declared, Guy Maresh: None declared, Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB

Extracellular vesicles from genetically unstable, oncogene-driven cancer cells trigger micronuclei formation in endothelial cells

Oncogenic transformation impacts cancer cell interactions with their stroma, including through formation of abnormal blood vessels. This influence is often attributed to angiogenic growth factors, either soluble, or associated with tumor cell-derived extracellular vesicles (EVs). Here we examine some of the cancer-specific components of EV-mediated tumor-vascular interactions, including the impact of genetic driver mutations and genetic instability. Cancer cells expressing mutant HRAS oncogene exhibit aberrations of chromatin architecture, aneuploidy, cytoplasmic chromatin deposition and formation of micronuclei with a non-random chromosome content. EVs released from such HRAS-driven cells carry genomic DNA, including oncogenic sequences, and transfer this material to endothelial cells while inducing abnormal formation of micronuclei, along with cell migration and proliferation. Micronuclei were also triggered following treatment with EVs derived from glioma cells (and stem cells) expressing EGFRvIII oncogene, and in both endothelial cells and astrocytes. EVs from HRAS and EGFRvIII-driven cancer cells carry 19 common proteins while EVs from indolent control cells exhibit more divergent proteomes. Immortalized endothelial cell lines with disrupted TP53 pathway were refractory to EV-mediated micronuclei induction. We suggest that oncogenic transformation and intercellular trafficking of cancer-derived EVs may contribute to pathological vascular responses in cancer due to intercellular transmission of genomic instability.

Quantitative proteomic analysis of trypsin-treated extracellular vesicles to identify the real-vesicular proteins

Extracellular vesicles (EVs) are nano-sized vesicles surrounded by a lipid bilayer and released into the extracellular milieu by most of cells. Although various EV isolation methods have been established, most of the current methods isolate EVs with contaminated non-vesicular proteins. By applying the label-free quantitative proteomic analyses of human colon cancer cell SW480-derived EVs, we identified trypsin-sensitive and trypsin-resistant vesicular proteins. Further systems biology and protein-protein interaction network analyses based on their cellular localization, we classified the trypsin-sensitive and trypsin-resistant vesicular proteins into two subgroups: 363 candidate real-vesicular proteins and 151 contaminated non-vesicular proteins. Moreover, the protein interaction network analyses showed that candidate real-vesicular proteins are mainly derived from plasma membrane (46.8%), cytosol (36.6%), cytoskeleton (8.0%) and extracellular region (2.5%). On the other hand, most of the contaminated non-vesicular proteins derived from nucleus, Golgi apparatus, endoplasmic reticulum and mitochondria. In addition, ribosomal protein complexes and T-complex proteins were classified as the contaminated non-vesicular proteins. Taken together, our trypsin-digested proteomic approach on EVs is an important advance to identify the real-vesicular proteins that could help to understand EV biogenesis and protein cargo-sorting mechanism during EV release, to identify more reliable EV diagnostic marker proteins, and to decode pathophysiological roles of EVs.

A reference map of the human binary protein interactome

Global insights into cellular organization and genome function require comprehensive understanding of the interactome networks that mediate genotype-phenotype relationships^1,2. Here, we present a human “all-by-all” reference interactome map of human binary protein interactions, or “HuRI”. With ~53,000 high-quality protein-protein interactions (PPIs), HuRI has approximately four times more such interactions than high-quality curated interactions from small-scale studies. Integrating HuRI with genome³, transcriptome⁴, and proteome⁵ data enables the study of cellular function within most physiological or pathological cellular contexts. We demonstrate the utility of HuRI in identifying specific subcellular roles of PPIs. Inferred tissue-specific networks reveal general principles for the formation of cellular context-specific functions and elucidate potential molecular mechanisms underlying tissue-specific phenotypes of Mendelian diseases. HuRI represents a systematic proteome-wide reference linking genomic variation to phenotypic outcomes.

Exposure to oral bisphosphonates and risk of gastrointestinal cancer

Few studies have explored the association of oral bisphosphonate exposure and gastrointestinal cancer within Asian populations. In this study, we investigated 45,397 Korean women from the nationwide population-based cohort from 2002 to 2013. Oral bisphosphonate exposure did not appear to be associated with elevated or reduced risk for gastrointestinal cancer.

INTRODUCTION

While several studies suggested increased risk in upper gastrointestinal (GI) cancer or reduced risk in colorectal cancer upon bisphosphonate exposure, the association is less explored within Asian populations. We investigated the effect of oral bisphosphonate exposure on the risk of GI cancers within a nationwide population-based cohort.

METHODS

This study used two separate cohorts. The first cohort included 45,397 women aged 60 years or older from the National Health Insurance Service-Health Screening Cohort during 2002-2013. Participants were classified into bisphosphonate users and non-users based on drug exposure during 2002-2007, and followed-up from the index date of January 1, 2008. The second cohort included 25,665 newly diagnosed osteoporosis patients who started taking oral bisphosphonate during 2003-2008. After 4 years of drug exposure period, patients were separated into quartiles based on cumulative oral bisphosphonate exposure. Participants were followed-up until December 31, 2013 for GI cancer, stomach cancer, and colorectal cancer. Cox proportional hazard regression models were used to assess the hazard ratios (HRs) and 95% confidence intervals (CIs) for the cancer risks.

RESULTS

Compared to bisphosphonate non-users, no significant risk difference was observed among bisphosphonate users on GI (HR 1.06; 95% CI 0.87-1.28), stomach (HR 1.11; 95% CI 0.85-1.47) and colorectal cancers (HR 1.04; 95% CI 0.79-1.37). Among bisphosphonate users, increasing doses of bisphosphonate exposure was not associated with elevated or reduced risk for GI cancer (p for trend 0.573).

CONCLUSION

Oral bisphosphonate use did not appear to be associated with elevated or reduced risk for GI cancers.

Spinal Stenosis in Familial Transthyretin Amyloidosis

Here we describe a patient with genetically confirmed ATTR, a family history of the disease and histological confirmation following carpal tunnel release surgery but no other manifestations. The first major neurological or systemic manifestation was cauda equina syndrome with ATTR deposits contributing to lumbar spinal stenosis. Recent gene therapy trials showed improvement in the neuropathy in TTR amyloidosis. This case highlights the need for awareness of the heterogeneous neurological phenotype seen in ATTR to aid earlier diagnosis especially now that disease modifying therapies are available.

P4393Current smoking and gender difference in South Korean AMI patients who underwent PCI with DES

Background

There is some debate on whether or not there is a gender difference is present between current smoking and cardiovascular disease.

Purpose

We decide to evaluate the impact of sex difference on the 2-year clinical outcomes in Korean acute myocardial infarction (AMI) patients who currently smoke and who underwent percutaneous coronary intervention (PCI) with drug-eluting stents (DES).

Methods

The data of this study was obtained from the Korea Acute Myocardial Infarction (KAMIR) registry. More than fifty high-volume universites or community hospitals with facilities for primary PCI and onsite cardiac surgery participated in this KAMIR registry. A total of 12565 current smoker AMI patients were enrolled and divided into the male (n=11767, 93.6%) or female (n=798, 6.4%) group. The clinical endpoint was the occurrence of major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), and total repeat revascularization.

Results

Before risk adjustment, the cumulative incidences of MACE (7.2% vs. 10.0%, hazard ratio [HR], 1.419; 95% confidence interval [CI], 1.125–1.790; P=0.003), all-cause death (HR, 1.988; 95% CI, 1.417–2.789; P<0.001), and re-MI (HR, 1.885; 95% CI, 1.154–3.078; P=0.011) were significantly higher in the female group compared with the male group. However, after adjustment the cumulative incidences of MACE (adjusted HR, 1.047; 95% CI, 0.756–1.450; P=0.782), all-cause death, re-MI, total repeat revascularization, TLR, TVR, and non-TVR were similar between the two groups.

Clinical outcomes at 2-year Outcomes Cumulative Events at 2-year (%) Unadjusted Adjusted* Propensity-score adjusted Male Female Log-rank Hazard Ratio (95% CI) p value Hazard Ratio (95% CI) p value Hazard Ratio (95% CI) p value MACE 819 (7.2) 78 (10.0) 0.003 1.419 (1.125–1.790) 0.003 1.047 (0.756–1.450) 0.782 1.133 (0.871–1.473) 0.352 All-cause death 283 (2.5) 38 (4.8) <0.001 1.988 (1.417–2.789) <0.001 0.764 (0.457–1.279) 0.306 1.105 (0.744–1.641) 0.620 Cardiac death 224 (1.9) 25 (3.2) 0.016 1.654 (1.094–2.500) 0.017 0.512 (0.261–1.005) 0.052 0.822 (0.511–1.322) 0.419 Re-MI 142 (1.3) 18 (2.4) 0.010 1.885 (1.154–3.078) 0.011 1.741 (0.887–3.419) 0.107 1.835 (1.109–3.375) 0.062 Total revascularization 444 (4.0) 27 (3.6) 0.594 0.900 (0.610–1.327) 0.594 1.069 (0.654–1.748) 0.789 0.956 (0.627–1.458) 0.835 TLR 121 (1.1) 8 (1.1) 0.956 0.980 (0.479–2.004) 0.956 0.955 (0.366–2.497) 0.926 0.868 (0.395–1.910) 0.726 TVR 228 (2.1) 14 (1.9) 0.726 0.908 (0.529–1.558) 0.726 1.051 (0.518–2.135) 0.890 0.935 (0.519–1.684) 0.823 Non-TVR 223 (2.0) 13 (1.7) 0.602 0.862 (0.493–1.508) 0.602 1.060 (0.536–2.097) 0.867 0.942 (0.514–1.726) 0.847

Conclusion

Before risk adjustment, a gender difference was suggested in the female group compared with the male in these current smoker South Korean AMI patients during a 2-year follow-up period. However, after adjustment, gender difference was not observed in these AMI patients with a history of current smoking.

P833Two-year clinical outcomes between statin with ACE inhibitor or ARB in patients with ST-segment elevation myocardial infarction after successful PCI with DES

Background

Limited comparative data are available.

Purpose

We decided to compare 2-year major clinical outcomes between statin with ACEI and statin ARB therapy in patients with STEMI after PCI with drug-eluting stents (DES).

Methods

A total 11706 STEMI patients who underwent PCI with DES and who prescribed statin were enrolled and they were divided into two groups, the statin with ACEI group (n=8705) and the statin with ARB group (n=3001). The primary endpoint was the major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), target lesion revascularization (TLR), target vessel revascularization (TVR), non-TVR. The secondary endpoints were the cumulative incidences of individual components of MACE and target vessel failure (TVF), a composite of death related to the target vessel, re-MI, or clinically driven TVR.

Results

Two PSM groups (2835 pairs, n=5670, C-statistic = 0.680) were generated. The relative risk of MACE was higher in the statin with ARB group compared to statin with ACEI groups after propensity score-matched (PSM) analysis (hazard ratio [HR]: 1.323, 95% confidence interval [CI]: 1.085–1.613, p=0.006). The relative risks of cardiac death (HR: 1.831, 95% CI: 1.199–2.740, p=0.005), total repeat revascularization (HR: 1.487, 95% CI: 1.133–1.950, p=0.004), and non-TVR (HR: 1.696, 95% CI: 1.122–2.564, p=0.012) were also higher in the statin with ARB group after PSM.

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value Statin + ACEI Statin + ARB Log-rank Propensity score matched Patients MACE 173 (6.5) 225 (8.5) 0.006 1.323 (1.085–1.613) 0.006 All-cause death 58 (2.2) 80 (3.0) 0.054 1.391 (0.992–1.950) 0.056 Cardiac death 35 (1.3) 63 (2.3) 0.004 1.831 (1.199–2.740) 0.005 Re-MI 39 (1.5) 44 (1.7) 0.548 1.141 (0.742–1.756) 0.548 Total repeat revascularization 88 (3.4) 128 (4.9) 0.004 1.487 (1.133–1.950) 0.004 TLR 26 (1.0) 40 (1.5) 0.075 1.561 (0.953–2.558) 0.077 TVR 53 (2.0) 71 (2.8) 0.086 1.364 (0.955–1.946) 0.088 Non-TVR 36 (1.4) 60 (2.3) 0.011 1.696 (1.122–2.564) 0.012 TVF 140 (5.3) 173 (6.6) 0.050 1.249 (1.000–1.561) 0.050

Conclusions

In this study, we suggest that the combination of statin with ACEI may be beneficial for reducing the cumulative incidences of MACE, total repeat revascularization rate, and non-TVR rather than the statin with ARB after PCI with DES in STEMI patients.

P5362Impact of statin therapy on long-term clinical outcomes between STEMI and NSTEMI after stent implantation

Background

Although European guideline recommends that statin should be given to all patients with acute myocardial infarction (AMI), irrespective of cholesterol concentration, limited studies were focused on the long-term effects of statin therapy between ST-segment elevation MI (STEMI) and non-ST-segment elevation MI (NSTEMI).

Purpose

The authors conducted the study to compare the relative beneficial role of statin on 2-year major clinical outcomes between STEMI and NSTEMI in patients who underwent successful PCI with DES.

Methods

Finally, a total of 26317 AMI patients who underwent stent implantation and who were prescribed the statin were enrolled and they were separated into two groups; the STEMI group (n=15002) and the NSTEMI group (n=11315). The clinical endpoint was the occurrence of major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), total coronary revascularization (target lesion revascularization [TLR], target vessel revascularization [TVR], non-TVR) during 2-year follow-up period.

Results

After propensity score-matched (PSM) analysis, two PSM groups (7746 pairs, n=15492, C-statistic = 0.766) were generated. In the total study population, the cumulative incidences of MACE, all-cause death, and cardiac death were significantly higher in the NSTEMI group. However, after PSM, the cumulative incidence of all-cause death (Hazard ratio, 1.386; 95% CI, 1.133–1.696; p=0.002) was significantly higher in the NSTEMI group. The cumulative incidences of MACE, cardiac death, re-MI, total revascularization, TLR, TVR, and non-TVR were similar between the two groups (Table 1).

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value STEMI NSTEMI Log-rank Propensity score matched patients MACE 532 (7.2) 584 (8.1) 0.092 1.106 (0.984–1.244) 0.092 All-cause death 163 (2.2) 224 (3.1) 0.001 1.386 (1.133–1.696) 0.002 Cardiac death 121 (1.5) 148 (2.0) 0.088 1.232 (0.969–1.566) 0.089 Re-MI 117 (1.6) 107 (1.5) 0.545 0.922 (0.710–1.199) 0.545 Total revascularization 291 (4.1) 307 (4.4) 0.422 1.068 (0.910–1.254) 0.423 TLR 92 (1.3) 89 (1.2) 0.880 0.978 (0.731–1.309) 0.880 TVR 173 (2.4) 184 (2.6) 0.478 1.078 (0.876–1.327) 0.478 Non-TVR 123 (1.7) 130 (1.9) 0.593 1.070 (0.836–1.369) 0.539

Conclusion

The mortality reduction capability of statin was more prominent in the STEMI group compared with the NSTEMI group.

P5494Impact of the gender difference on long-term clinical outcomes in dyslipidemic South Korean AMI patients who underwent PCI with new-generation DES

Background

There are limited comparative data concerning long-term major clinical outcomes between male and female in dyslipidemic AMI patients after PCI with new-generation DES.

Purpose

We thought to investigate the impact of gender difference on the 2-year clinical outcomes.

Methods

Finally, a total of 2403 eligible dyslipidemic AMI patients who underwent PCI with new-generation DES were enrolled and they were separated into two groups; the male group (n=1800) and the female group (n=603). The primary endpoint was major adverse cardiac events (MACE) defined as all-cause death, recurrent myocardial infarction (re-MI), target lesion revascularization (TLR), and target vessel revascularization (TVR). The secondary endpoints were the incidence of the individual components of MACE and target vessel failure (TVF), a composite of death related to the target vessel, re-MI, or clinically driven TVR

Results

Two propensity score-matched (PSM) groups (422 pairs, n=844, C-statistic = 0.850) were generated. In the total study population, the cumulative incidences of MACE, all-cause death, re-MI, and TVF were significantly higher in the female group compared with the male group. However, after propensity score-matched (PSM) analysis, the cumulative incidences of MACE (HR, 0.971; 95% CI, 0.628–1.501; p=0.895), all-cause death (HR, 1.061; 95% CI, 0.536–2.100; p=0.865), re-MI (HR, 1.212; 95% CI, 0.433–2.907; p=0.813), and TVF (HR, 0.764; 95% CI, 0.474–1.229; p=0.267) were similar between the two groups. In addition, the cumulative incidences of cardiac death, TLR, TVR were not significantly different between the two groups (Table 1).

Outcomes Cumulative Events at 2-year (%) Hazard Ratio (95% CI) p value Male Female Log-rank Propensity score matched patients MACE 41 (10.4) 40 (10.3) 0.895 0.971 (0.628–1.501) 0.895 All-cause death 16 (4.0) 17 (4.2) 0.865 1.061 (0.536–2.100) 0.865 Cardiac death 13 (3.3) 9 (2.2) 0.391 0.691 (0.295–1.616) 0.393 Re-MI 8 (2.0) 9 (2.4) 0.813 1.212 (0.433–2.907) 0.813 TLR 7 (1.8) 6 (1.6) 0.781 0.857 (0.298–2.550) 0.781 TVR 16 (4.3) 10 (2.7) 0.236 0.623 (0.283–1.373) 0.241 TVF 39 (10.2) 30 (7.8) 0.265 0.764 (0.474–1.229) 0.267

Conclusion

The gender difference was not apparent in these dyslipidemic South Korean AMI patients who underwent PCI with new-generation DES during 2-year follow-up period.

Mapping Subpopulations of Cancer Cell-Derived Extracellular Vesicles and Particles by Nano-Flow Cytometry

The elusive complexity of membranous extracellular vesicle (EV) and membrane-less extracellular particle (EP) populations released from various cellular sources contains clues as to their biological functions and diagnostic utility. In this study, we employed optimized multicolor nano-flow cytometry, structured illumination (SIM), and atomic force microscopy (AFM) to bridge sensitive detection at the single EV/EP level and high-throughput analysis of cancer cell secretomes. We applied these approaches to particles released from intact cells driven by several different transforming mechanisms or to cells under therapeutic stress imposed by pharmacological inhibition of their oncogenic drivers, such as epidermal growth factor receptor (EGFR). We demonstrate a highly heterogeneous distribution of biologically relevant elements of the EV/EP cargo, including oncoproteins (EGFR), clotting factors (tissue factor), pro-metastatic integrins (ITGA6, ITGA4), tetraspanins (CD63), and genomic DNA across the entire particulate secretome of cancer cells. We observed that targeting EGFR activity with irreversible kinase inhibitors (dacomitinib) triggers emission of DNA containing EP/EV subpopulations, including particles (chromatimeres) harboring both EGFR and DNase-resistant chromatin. While nano-flow cytometry enables quantification of these changes across the entire particular secretome, SIM reveals individual molecular topography of EV/EP subsets and AFM exposes some of their physical properties, including the presence of nanofilaments and other substructures. We describe differential uptake rates of distinct EV subsets, resulting in preferential internalization of exosome-like small EVs by cancer cells to the exclusion of larger EVs. Thus, our study illustrates the potential of nano-flow cytometry coupled with high-resolution microscopy to explore the cancer-related EV/EP landscape.

P02.01 Analysis of Multimodal Intraoperative Monitoring During Intramedullary Spinal Ependymoma Surgery

BACKGROUND

To evaluate the validity of intraoperative somatosensory-evoked potential (SSEP) and motor-evoked potential (MEP) monitoring according to two different warning criteria for 6 months after intramedullary spinal ependymoma (IMSE) surgery.

MATERIAL AND METHODS

To evaluate the validity of intraoperative somatosensory-evoked potential (SSEP) and motor-evoked potential (MEP) monitoring according to two different warning criteria for 6 months after intramedullary spinal ependymoma (IMSE) surgery.

RESULTS

The success rates of SSEP and MEP monitoring were 84.9% and 83.7%, respectively. There was one indeterminate case in SSEP and six in MEP. All-or-none criterion in SSEP and MEP monitoring showed higher specificity, PPV, and DOR than 50% decline criterion during 6 months. During the follow up, 37 of 38 extremities (97.4%) and 21 of 29 extremities (72.4%) were observed the improvement of sensory and motor deficit, respectively. Seven indeterminate cases also showed good clinical outcomes. However, most patients remained some degree of neurologic deficit.

CONCLUSION

Many false positive and false negative results of SSEP and MEP monitoring occurred immediately postoperative period. All-or-none criterion was more beneficial for IMSE surgery than 50% decline criterion. This trend was maintained until 6 months after surgery.

P92 What is a benign notochordal cell tumour?

Objectives

Characteristics from a large systematic review.

Design

The first systematic review of benign notochordal cell tumours.

Subjects

All studies, in any language, published at any time, identified using specified search terms.

Methods

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

Results

So-called benign notochordal cell tumours exhibited the following features: pain was the sole presenting symptom in 37/81 (45.7%) and neurological deficit in 36/81 (44.4%). Incidental discovery upon imaging was reported in 8/81 (9.9%). Radiologically, lesions were small, (≤30 millimetres at their maximum diameter) in 57/65 (87.7%), hypointense on T1 sequences and hyperintense on T2 sequences on magnetic resonance imaging (106/130; 81.5%), did not enhance following contrast administration (62/74; 83.8%) and were non-lytic (80/160; 50.0%). Histologically, these tumours lacked myxoid matrix (66/84; 78.6%) and nuclear atypia (100/112; 89.3%). In those managed conservatively, follow up was between 8.5 and 120 months. Most were stable at follow up (22/25; 88.0%), one lesion grew (4.0%), one patient died of an unrelated cause (4.0%) and outcome was not stated in one case (4.0%).

Conclusions

BNCTs exhibit a spectrum of features, none of which are pathognomonic and diagnosis is subjective. The majority of reports describe small, non-progressive, non-lytic lesions that lack contrast enhancement, intercellular myxoid matrix and nuclear atypia. They are nevertheless difficult to distinguish from small chordomas.

P25 Hydrogel systems to enhance the delivery of cell therapy for traumatic spinal cord injury

Objectives

Cell therapies are an emerging therapeutic approach for spinal cord injury. We assessed the survival and phenotype of olfactory ensheathing cells (OECs) in hydrogel delivery systems suitable for clinical use.

Design

Laboratory study.

Methods

Cell survival in different formulations of collagen and fibrin hydrogels was assessed using Syto 9 and propidium iodide. The proportion of cells staining positive for a key repair marker (p75NTR) was also quantified using immunocytochemistry and fluorescence microscopy.

Results

There were significant differences in OEC survival between the various collagen and fibrin hydrogel formulations tested (p<0.001 one-way ANOVA, n=17). 10% v/v fibrin conferred the best cell survival with 85% of OECs remaining alive. Incorporating OECs into collagen hydrogels promoted the highest proportion of p75NTR immunopositive cells (78%) and this was significantly higher than both fibrin hydrogels and traditional monolayer culture (53% and 20%, respectively, p<0.0001 one-way ANOVA, n=24).

Conclusions

Collagen and fibrin hydrogels both have the potential to enhance the delivery, survival and retention of transplanted OECs for spinal cord repair. Both materials are clinically scalable, promote favourable OEC survival and have the potential to increase the proportion of cells expressing a key repair marker (p75NTR). Optimised hydrogel delivery systems may provide a valuable approach to improve the delivery of OECs for spinal cord repair in the future.

Oncogenic Regulation of Extracellular Vesicle Proteome and Heterogeneity

Mutational and epigenetic driver events profoundly alter intercellular communication pathways in cancer. This effect includes deregulated release, molecular composition, and biological activity of extracellular vesicles (EVs), membranous cellular fragments ranging from a few microns to less than 100 nm in diameter and filled with bioactive molecular cargo (proteins, lipids, and nucleic acids). While EVs are usually classified on the basis of their physical properties and biogenetic mechanisms, recent analyses of their proteome suggest a larger than expected molecular diversity, a notion that is also supported by multicolour nano-flow cytometry and other emerging technology platforms designed to analyze single EVs. Both protein composition and EV diversity are markedly altered by oncogenic transformation, epithelial to mesenchymal transition, and differentiation of cancer stem cells. Interestingly, only a subset of EVs released from mutant cells may carry oncogenic proteins (e.g., EGFRvIII), hence, these EVs are often referred to as "oncosomes". Indeed, oncogenic transformation alters the repertoire of EV-associated proteins, increases the presence of pro-invasive cargo, and alters the composition of distinct EV populations. Molecular profiling of single EVs may reveal a more intricate effect of transforming events on the architecture of EV populations in cancer and shed new light on their biological role and diagnostic utility.

Extracellular Vesicles as Conduits of Non-Coding RNA Emission and Intercellular Transfer in Brain Tumors

Non-coding RNA (ncRNA) species have emerged in as molecular fingerprints and regulators of brain tumor pathogenesis and progression. While changes in ncRNA levels have been traditionally regarded as cell intrinsic there is mounting evidence for their extracellular and paracrine function. One of the key mechanisms that enables ncRNA to exit from cells is their selective packaging into extracellular vesicles (EVs), and trafficking in the extracellular space and biofluids. Vesicular export processes reduce intracellular levels of specific ncRNA in EV donor cells while creating a pool of EV-associated ncRNA in the extracellular space and biofluids that enables their uptake by other recipient cells; both aspects have functional consequences. Cancer cells produce several EV subtypes (exosomes, ectosomes), which differ in their ncRNA composition, properties and function. Several RNA biotypes have been identified in the cargo of brain tumor EVs, of which microRNAs are the most studied, but other species (snRNA, YRNA, tRNA, and lncRNA) are often more abundant. Of particular interest is the link between transforming oncogenes and the biogenesis, cargo, uptake and function of tumor-derived EV, including EV content of oncogenic RNA. The ncRNA repertoire of EVs isolated from cerebrospinal fluid and serum is being developed as a liquid biopsy platform in brain tumors.