Neutrophil extracellular traps inhibit osteoclastogenesis

Neutrophil extracellular traps (NETs) released by neutrophils upon inflammation or infection, act as an innate immune defense against pathogens. NETs also influence inflammatory responses and cell differentiation in host cells. Osteoclasts, which are derived from myeloid stem cells, are critical for the bone remodeling by destroying bone. In the present study, we explores the impact of NETs, induced by the inflammatory agent calcium ionophore A23187, on the differentiation and activation of osteoclasts, potentially through suppressing RANK expression. Our results collectively suggested that the inhibition of RANKL-mediated osteoclastogenesis by NETs might lead to the suppression of excessive bone resorption during inflammation.

Identifying prognostic biomarkers for palbociclib add-on therapy in fulvestrant-resistant breast cancer using cell-free DNA sequencing

BACKGROUND

The FUTURE trial (UMIN000029294) demonstrated the safety and efficacy of adding palbociclib after fulvestrant resistance in patients with hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) advanced and metastatic breast cancer (ABC/MBC). In this planned sub-study, cancer panel sequencing of cell-free DNA (cfDNA) was utilized to explore prognostic and predictive biomarkers for further palbociclib treatment following fulvestrant resistance.

MATERIALS AND METHODS

Herein, 149 cfDNA samples from 65 patients with fulvestrant-resistant disease were analysed at the time of palbociclib addition after fulvestrant resistance (baseline), on day 15 of cycle 1, and at the end of treatment using the assay for identifying diverse mutations in 34 cancer-related genes.

RESULTS

During the course of treatment, mutations in ESR1, PIK3CA, FOXA1, RUNX1, TBX3, and TP53 were the most common genomic alterations observed. Analysis of genomic mutations revealed that before fulvestrant introduction, baseline PIK3CA mutations were marginally lower in metastatic aromatase inhibitor (AI)-treated patients compared to adjuvant AI-treated patients (P = 0.063). Baseline PIK3CA mutations were associated with poorer progression-free survival [hazard ratio: 1.62, P = 0.04]. Comparative analysis between baseline and early-changing gene mutations identified poor prognostic factors including early-changing MAP3K1 mutations (hazard ratio: 4.66, P = 0.04), baseline AR mutations (hazard ratio: 3.53, P = 0.04), and baseline PIK3CA mutations (hazard ratio: 3.41, P = 0.02). Notably, the relationship between ESR1 mutations and mutations in PIK3CA, MAP3K1, and TP53 weakened as treatment progressed. Instead, PIK3CA mutations became correlated with TP53 and FOXA1 mutations.

CONCLUSIONS

Cancer panel testing for cfDNA identified prognostic and predictive biomarkers for palbociclib add-on therapy after acquiring fulvestrant resistance in patients with HR+/HER2- ABC/MBC.

Improved Measurements of Muonic Helium Ground-State Hyperfine Structure at a Near-Zero Magnetic Field

Muonic helium atom hyperfine structure (HFS) measurements are a sensitive tool to test the three-body atomic system and bound-state quantum electrodynamics theory, and determine fundamental constants of the negative muon magnetic moment and mass. The world's most intense pulsed negative muon beam at the Muon Science Facility of the Japan Proton Accelerator Research Complex allows improvement of previous measurements and testing further CPT invariance by comparing the magnetic moments and masses of positive and negative muons (second-generation leptons). We report new ground-state HFS measurements of muonic helium-4 atoms at a near-zero magnetic field, performed for the first time using a small admixture of CH_{4} as an electron donor to form neutral muonic helium atoms efficiently. Our analysis gives Δν=4464.980(20)  MHz (4.5 ppm), which is more precise than both previous measurements at weak and high fields. The muonium ground-state HFS was also measured under the same conditions to investigate the isotopic effect on the frequency shift due to the gas density dependence in He with CH_{4} admixture and compared with previous studies. Muonium and muonic helium can be regarded as light and heavy hydrogen isotopes with an isotopic mass ratio of 36. No isotopic effect was observed within the current experimental precision.

Effect of newly developed scissors-attached micro-forceps on the recipient clamp time and occurrence of anastomotic site infarction after bypass surgery for moyamoya disease

Introduction

This study aimed to examine the effect of newly developed scissors-attached micro-forceps in superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease (MMD).

Materials and methods

Of 179 consecutive STA-MCA anastomoses on 95 hemispheres of 71 MMD patients at the University of Fukui Hospital between 2009 and 2023, 49 anastomoses on 26 hemispheres of 21 patients were enrolled in this retrospective cohort clinical trial intraoperative indocyanine green video-angiography did not demonstrate bypass patency in three anastomoses in two patients who were excluded. Twenty-one anastomosis in 19 hemispheres of 16 patients were performed using the conventional micro-forceps (conventional group, CG), and 25 anastomoses in 22 hemispheres of 19 patients were performed using scissors-attached micro-forceps (scissors group, SG). A small infarction near the anastomotic site detected using postoperative diffusion-weighted imaging was defined as anastomotic site infarction (ASI). Factors affecting the occurrence of ASI were examined by univariate, logistic regression, and receiver operating curve (ROC) analysis.

Results

There were no significant differences in clinical parameters such as age, sex, number of sacrificed branches, number of sacrificed large branches, and number of sutures between the CG and SG. However, the clamp time and occurrence of ASI were significantly lower in the SG than in the CG. Logistic regression analysis revealed that the clamp time was the only significant factor predicting the occurrence of ASI. A receiver operating curve analysis also revealed that the clamp time significantly predicted the occurrence of ASI (area under the curve, 0.875; cutoff value, 33.2 min).

Conclusion

The newly developed scissors-attached micro-forceps could significantly reduce the clamp time and occurrence of ASI in STA-MCA anastomosis for MMD.

Macrophage migration inhibitory factor-mediated mast cell extracellular traps induce inflammatory responses upon Fusobacterium nucleatum infection

Mast cell extracellular traps (MCETs) released by mast cells contribute to host defense. In this study, we investigated the effects of MCETs released from mast cells after infection with a periodontal pathogen Fusobacterium nucleatum. We found that F. nucleatum induced MCET release from mast cells, and that MCETs expressed macrophage migration inhibitory factor (MIF). Notably, MIF bound to MCETs induced proinflammatory cytokine production by monocytic cells. These findings suggest that MIF expressed on MCETs, released from mast cells upon infection with F. nucleatum, promotes inflammatory responses that may be associated with the pathogenesis of periodontal disease.

[A Study of the Safety of Chemotherapy with Generic Oxaliplatin for the Treatment of Colorectal Cancer]

BACKGROUND

Generic oxaliplatin is widely used in colorectal cancer chemotherapy; however, studies on the adverse events of generic drugs are limited. We investigated the safety of brand-name and generic oxaliplatin used in capecitabine plus oxaliplatin(plus bevacizumab: Bmab)for colorectal cancer treatment.

PARTICIPANTS AND METHODS

A total of 86 patients who newly started CAPOX(plus Bmab)between January 2018 and January 2022 were included in this retrospective study, excluding those who changed to generic from the brand-name drug during the chemotherapy course.

RESULTS

Forty-seven patients(54.6%)were in the generic drug(GE)group, while 39 patients(45.4%)were in the brand drug(EP)group. No significant difference was observed in the patient characteristics between the GE and EP groups. The median number of oxaliplatin administrations were 4 and 5 cycles in the GE and EP groups, respectively. Neutropenia of Grade 2 or higher was observed in 51.1%(24 patients)and 33.3%(13 patients)in the GE and EP groups, respectively. Hypersensitivity was observed in 14.9%(7 patients)and 7.7%(3 patients)in the GE and EP groups, respectively.

CONCLUSION

There were no statistically significant differences between generic and brand-name oxaliplatin in the frequency of adverse events.

Development of Ternary Ti-Ag-Cu Alloys with Excellent Mechanical Properties and Antibiofilm Activity

Titanium-20 mass% Silver (Ti-20%Ag) alloy can suppress biofilm formation on the surface. Unlike bactericidal agents, it does not kill bacteria; therefore, the healthy oral microflora remains undisturbed. To utilize the unique functions of this alloy and enable its use in the fabrication of dental prostheses that require relatively high strength, we added copper (Cu) as an alloying element to improve strength. This study aimed to develop ternary Ti-Ag-Cu alloys with excellent mechanical properties and antibiofilm activity. As a result of investigating the mechanical properties of several experimental alloys, the tensile strength, yield strength, and hardness of Ti-20%Ag-1%Cu and Ti-20%Ag-2%Cu alloys were improved by the solid-solution strengthening or hardening of the αTi phase. In addition, these alloys had the same ability to suppress biofilm formation as the Ti-20Ag alloy. Thus, Ti-20%Ag-1-2%Cu alloys can be used for fabrication of narrow-diameter dental implants and prostheses subjected to extremely high force, and these prostheses are useful in preventing post-treatment oral diseases.

Reactivation of p53 by RITA Induces Apoptosis in Human Oral Squamous Cell Carcinoma Cells

BACKGROUND/AIM

Oral squamous cell carcinoma (OSCC) is one of the most common tumors of the head and neck region. The tumor suppressor gene p53 (TP53) is the most frequently mutated gene in OSCC and TP53 mutations are associated with decreased survival and resistance to chemotherapy in patients with OSCC. Therefore, therapeutic strategies targeting TP53 reactivation are required to effectively treat OSCC. In this study, we investigated the effect of various p53-reactivating small molecules (RITA, PRIMA-1, and CP-31398) on the proliferation of human OSCC cell lines (Ca9-22, HSC-2, HSC-3, and HSC-4) derived from human oral tissues bearing a mutant TP53 gene.

MATERIALS AND METHODS

Apoptosis induction by RITA was assessed by measuring Annexin V and propidium iodide (PI)-positive cells using flow cytometry. p53 and murine double minute 2 (MDM2) phosphorylation and Bax expression were detected in the lysates of RITA-treated Ca9-22 cells using western blotting.

RESULTS

RITA markedly inhibited the growth of Ca9-22, HSC-2, HSC-3, and HSC-4 cells. In Ca9-22 cells, RITA induced apoptosis and inhibited cell proliferation while increasing p53 phosphorylation and Bax expression; however, RITA did not induce MDM2 phosphorylation.

CONCLUSION

The inhibitory effect of RITA on human OSCC cell proliferation is mediated by apoptosis induction through p53 and Bax.

Extracellular Vesicles Derived From Murine Cementoblasts Possess the Potential to Increase Receptor Activator of Nuclear Factor-κB Ligand-Induced Osteoclastogenesis

Cementum resorption, unlike bone resorption, is clinically known to occur only with limited pathological stimuli, such as trauma, orthodontic forces, and large apical periodontitis; however, the molecular mechanisms that control osteoclast formation on the cementum surface remain unclear. In this study, we focused on extracellular vesicles (EVs) secreted by cementoblasts and analyzed their effects on osteoclast differentiation. EVs were extracted from the conditioned medium (CM) of the mouse cementoblast cell line OCCM-30. Transmission electron microscopy (TEM) analysis confirmed the presence of EVs with a diameter of approximately 50–200 nm. The effect of the EVs on osteoclast differentiation was examined using the mouse osteoclast progenitor cell line RAW 264.7 with recombinant receptor activator of nuclear factor (NF)-κB ligand (rRANKL) stimulation. EVs enhanced the formation of tartrate-resistant acid phosphatase (TRAP) activity-positive cells upon rRANKL stimulation. EVs also enhanced the induction of osteoclast-associated gene and protein expression in this condition, as determined by real-time PCR and Western blotting, respectively. On the other hand, no enhancing effect of EVs was observed without rRANKL stimulation. A Western blot analysis revealed no expression of receptor activator of NF-κB ligand (RANKL) in EVs themselves. The effect on rRANKL-induced osteoclast differentiation was examined using the CM of cementoblasts in terms of TRAP activity-positive cell formation and osteoclast-associated gene expression. The conditioned medium partly inhibited rRANKL-induced osteoclast differentiation and almost completely suppressed its enhancing effect by EVs. These results indicate that cementoblasts secreted EVs, which enhanced RANKL-induced osteoclast differentiation, and simultaneously produced soluble factors that neutralized this enhancing effect of EVs, implicating this balance in the regulation of cementum absorption. A more detailed understanding of this crosstalk between cementoblasts and osteoclasts will contribute to the development of new therapies for pathological root resorption.

Porphyromonas gingivalis Gingipains-Mediated Degradation of Plasminogen Activator Inhibitor-1 Leads to Delayed Wound Healing Responses in Human Endothelial Cells

Plasminogen activator inhibitor-1 (PAI-1), a serine protease inhibitor, is constitutively produced by endothelial cells and plays a vital role in maintaining vascular homeostasis. Chronic periodontitis is an inflammatory disease characterized by bleeding of periodontal tissues that support the tooth. In this study, we aimed to determine the role of PAI-1 produced by endothelial cells in response to infections caused by the primary periodontal pathogen Porphyromonas gingivalis. We demonstrated that P. gingivalis infection resulted in significantly reduced PAI-1 levels in human endothelial cells. This reduction in PAI-1 levels could be attributed to the proteolysis of PAI-1 by P. gingivalis proteinases, especially lysine-specific gingipain-K (Kgp). We demonstrated the roles of these degradative enzymes in the endothelial cells using a Kgp-specific inhibitor and P. gingivalis gingipain-null mutants, in which the lack of the proteinases resulted in the absence of PAI-1 degradation. The degradation of PAI-1 by P. gingivalis induced a delayed wound healing response in endothelial cell layers via the low-density lipoprotein receptor-related protein. Our results collectively suggested that the proteolysis of PAI-1 in endothelial cells by gingipains of P. gingivalis might lead to the deregulation of endothelial homeostasis, thereby contributing to the permeabilization and dysfunction of the vascular endothelial barrier.

Achilles tendon thickness assessed by X-ray predicting a pathogenic mutation in familial hypercholesterolemia gene

Background

The 2017 Japan Atherosclerosis Society (JAS) familial hypercholesterolemia (FH) criteria adopts a cut off value of ≥9 mm of Achilles tendon thickness (ATT) detected by X-ray as one of the three key items. This threshold was determined based on an old data assessing ATT of 36 non-FH individuals published in 1977. Although the specificity of this clinical criteria is extremely high due to a strict threshold, there are substantial number of patients with FH whose ATT <9 mm. We aimed to determine a cut off value of ATT detected by X-ray to differentiate FH and non-FH based on genetic diagnosis.

Methods

The individuals (male/female = 486/501) with full assessments of genetic analyses for FH-genes (LDLR, and PCSK9), serum lipids, and ATT detected by X-ray at Kanazawa University Hospital and National Cerebral and Cardiovascular Center Research Institute were included in this study. Receiver operating characteristic (ROC) analyses were performed to determine a better cut off point of ATT predicting a pathogenic mutation of FH.

Results

ROC analyses revealed the best cut off values of ATT as 7.6 mm for male, and 7.0 mm for female with the sensitivities and specificities of 0.83 and 0.83 for male and 0.86 and 0.85 for female, respectively. If the thresholds of ATT of 8.0/7.5 mm and 7.5/7.0 mm were applied to diagnose of male/female FH, the sensitivities/specificities predicting a pathogenic mutation of FH by the 2017 JAS FH clinical criteria would be 0.82/0.90 and 0.85/0.88, respectively.

Conclusions

These results suggest that the cut-off value of ATT detected by X-ray is obviously lower than 9.0 mm adopted by the 2017 JAS FH clinical criteria.

Funding Acknowledgement

Type of funding sources: None.

Direct comparison of bioabsorbable and biodurable polymer everolimus-eluting stent in neointimal stent coverage and in-stent thrombus using high-resolution angioscope

Background/Introduction

Although second-generation drug eluting stent (DES) employing biodurable polymer drastically shortened the duration of dual antiplatelet therapy (DAPT), previous reports raised concerns that switching from DAPT to single antiplatelet therapy increased rates of subsequent stent thrombosis with time. Third-generation DES employing bioabsorbable polymer has been introduced so as not to hinder the healing process of the vessel wall, however, at present, both DES with bioabsorbable polymer and those with biodurable polymer are used in parallel. It means there is no conclusive evidence regarding pros and cons of these two types of polymers.

Purpose

This study aims to clarify how bioabsorbable polymer and biodurable polymer act on the human coronary artery by observing neointimal stent coverage (NIC) and in-stent thrombus by comparing the third-generation DES with bioabsorbable-polymer cobalt-platinum everolimus-eluting stent (BP CoPt-EES), and the second-generation DES with biodurable-polymer cobalt-chromium everolimus-eluting stent (DP CoCr-EES).

Methods

This is a multicenter observational study including 11 hospitals. We investigated 70 stents (BP CoPt-EES: 40, DP CoCr-EES: 30) of 60 cases, who underwent stent implantation followed by simultaneous observation by coronary angiography, IVUS and angioscopy within 6 to 12 months. For angioscopy, we used a recently available, high-resolution angioscope with a pixel count of 9,000 which realized both stent coverage analysis and planar thrombus detection precisely. Neointimal stent coverage was graded from G0: non coverage to G3: full coverage, and heterogeneity value of neointima was measured as the difference between maximum and minimum NIC grade.

Results

A strong relationship was observed between NIC grade and in-stent thrombus in all stents (p=0.0011), and between the heterogeneity value and stent thrombus (p=0.012). There was no statistical difference in NIC grade between BP CoPt-EES vs. DP CoCr-EES; grade 0: 0 (0.0%) vs. 2 (6.7%), grade 1: 13 (32.5%) vs. 11 (36.7%), grade 2: 6 (15.0%) vs. 6 (20.0%), grade 3: 21 (52.5%) vs. 11 (36.7%), p=0.17) and neither in the heterogeneity value of neointima (p=0.49). The ratio of stent thrombus did not reach statistical difference; 16 (40.0%) in BP CoPt-EES vs. 17 (56.7%) in DP CoCr-EES (p=0.23).

Conclusion

The existence of stent thrombus was associated with the neointimal stent coverage. There was no significant difference both in neointimal stent coverage and stent thrombus between bioabsorbable polymer cobalt-platinum EES and biodurable polymer cobalt-chromium EES after 6 to 12 months following stent deployment.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Boston Scientific JapanOvalis ltd

Impact of cumulative exposure to LDL cholesterol on cardiovascular events in patients with familial hypercholesterolemia

Aims

Recent studies suggest that cumulative exposure to LDL-cholesterol (LDL-C) leads to the development of atherosclerotic cardiovascular disease (ASCVD). However, few studies have investigated whether this link extends to individuals with familial hypercholesterolemia (FH), a relevant patient population. We aimed to determine whether cholesterol-year-score, an indicator of cumulative exposure to LDL-C, is associated with ASCVD events among Japanese patients with FH

Methods and results

We retrospectively investigated the health records of 1,050 patients with clinical FH diagnosis who were referred to our institute between April 1990 and March 2019. We used Cox proportional hazards models adjusted for established ASCVD risk factors to assess the association between cholesterol-year-score and major adverse cardiovascular events (MACEs), including death from any cause or hospitalization due to ASCVD events. Cholesterol-year-score was calculated as LDL-C max × [age at diagnosis / statin initiation] + LDL-C at inclusion × [age at inclusion − age at diagnosis / statin initiation]. The median follow-up period for MACE evaluation was 12.3 (interquartile range, 9.1–17.5) years, and 177 patients experienced MACEs during the observation period. Cholesterol-year-score was significantly associated with MACEs (hazard ratio [HR], 1.35; 95% confidence interval, 1.07–1.53; P=0.0034, per 1,000 mg-year/dL), independent of other traditional risk factors including age and LDL-C, based on cross-sectional assessment. Cholesterol-year-score improved the discrimination ability of other traditional risk factors for ASCVD events (C-index, 0.901 versus 0.889; P=0.00473).

Conclusion

Cumulative LDL-C exposure was strongly associated with MACEs in Japanese patients with FH, warranting early diagnosis and treatment initiation in these patients.

Funding Acknowledgement

Type of funding sources: None.

Nitrogen-containing bisphosphonates and lipopolysaccharide mutually augment inflammation via adenosine triphosphate (ATP)-mediated and interleukin 1β (IL-1β)-mediated production of neutrophil extracellular traps (NETs)

Among the bisphosphonates (BPs), nitrogen-containing BPs (N-BPs) have much stronger anti-bone-resorptive actions than non-N-BPs. However, N-BPs have various side effects such as acute influenza-like reactions after their initial administration and osteonecrosis of the jawbones after repeated administration. The mechanisms underlying such effects remain unclear. To overcome these problems, it is important to profile the inflammatory nature of N-BPs. Here, we analyzed the inflammatory reactions induced in mouse ear pinnae by the N-BPs alendronate (Ale) and zoledronate (Zol). We found the following: (i) Ale and Zol each induced two phases of inflammation (early weak and late strong ear swelling); (ii) both phases were augmented by lipopolysaccharides (LPSs; cell-surface constituent of gram-negative bacteria, including oral bacteria), but prevented by inhibitors of the phosphate transporters of solute carrier 20/34 (SLC20/SLC34); (iii) macrophages and neutrophils were involved in both phases of Ale+LPS-induced ear-swelling; (iv) Ale increased or tended to increase various cytokines, and LPS augmented these effects, especially that on interleukin 1β (IL-1β); (v) adenosine triphosphate (ATP) was involved in both phases, and Ale alone or Ale+LPS increased ATP in ear pinnae; (vi) the augmented late-phase swelling induced by Ale+LPS depended on both IL-1 and neutrophil extracellular traps (NETs; neutrophil-derived net-like complexes); (vii) neutrophils, together with macrophages and dendritic cells, also functioned as IL-1β-producing cells, and upon stimulation with IL-1β, neutrophils produced NETs; (viii) stimulation of the purinergic 2X7 (P2X7) receptors by ATP induced IL-1β in ear pinnae; (ix) NET formation by Ale+LPS was confirmed in gingiva, too. These results suggest that (i) N-BPs induce both early-phase and late-phase inflammation via ATP-production and P2X7 receptor stimulation; (ii) N-BPs and LPS induce mutually augmenting responses both early and late phases via ATP-mediated IL-1β production by neutrophils, macrophages, and/or dendritic cells; and (iii) NET production by IL-1β-stimulated neutrophils may mediate the late phase, leading to prolonged inflammation. These results are discussed in relation to the side effects seen in patients treated with N-BPs. © 2021 American Society for Bone and Mineral Research (ASBMR).

Creation of mortality risk calculator using a I-123 mIBG-based machine learning model: differential prediction of arrhythmic death and heart-failure death

Funding Acknowledgements

Type of funding sources: None.

Background

Although I-123 meta-iodobenzylguanidine (mIBG) has been applied to patients with chronic heart failure (CHF), a diagnostic tool for differential prediction of fatal arrhythmic events (ArE) and heart-failure death (HFD) has been pursued. 

Purpose

The aim of this study was to create a calculator of mortality risk for differentiating mode of cardiac death using a machine learning (ML) method, and to test the accuracy in a new cohort of patients with CHF.

Methods

A total of 529 patients with CHF was used as the training database for ML. The ArE group consisted of patients with arrhythmic death, sudden cardiac death and appropriate therapy by implantable cardioverter defibrillator. A heart-to-mediastinum ratio (H/M) standardized to the medium-energy collimator condition was calculated with a planar anterior mIBG scintigram. The best classifier models for predicting HFD and ArE were determined by four-fold cross validation. Input variables included age, sex, New York Heart Association (NYHA) functional class, left ventricular ejection fraction, ischemic etiology, mIBG H/M and washout rate, and b-type natriuretic peptide (BNP) or NT Pro BNP, estimated glomerular filtration rate, hemoglobin, and complications such as diabetes and hypertension. After creating the ML-based model, the constructed classifier functions for ArE, HFD, and survival were exported for subsequent use. A new cohort of patients (n = 312, age 67 ± 13 years, 2015 or later) was used to test the ML-based model.

Results

The training database included 141 events (27%) with ArE (7%) and HFD (20%). Receiver-operating characteristic analysis by four-fold validation showed area under the curve value of 0.90 for HFD and 0.73 for ArE. Among various ML methods, the logistic regression method demonstrated the most stable calculation of the probability of ArE followed by random forest and gradient boosted tree methods. Therefore, the logistic-regression method was used for calculating both HFD and ArE probabilities. In the test cohort, patients with a high HFD probability >8% resulted in 6.3-fold higher HFD than those with low probability (≤ 8%). Patients with high ArE probability >8% showed 2.5-fold higher ArE than those with low probability (≤ 8%).

Conclusion

The ML-based mortality risk calculator could be used for stratifying patients at high and low risks, which might be useful for estimating appropriate treatment strategy.

Prognostic impact of cascade screening for familial hypercholesterolemia on cardiovascular events

Background

Early diagnosis and timely treatment for the patients with familial hypercholesterolemia (FH) can substantially lower the risk of atherosclerotic cardiovascular disease (ASCVD). In this sense, cascade screening could be one of the most useful options. However, few data exist regarding the impact of cascade screening for FH on the reduction of risk of ASCVD events.

Objectives

We aimed to evaluate the prognostic impact of cascade screening for FH.

Methods

We retrospectively investigated the health records of 1,050 patients with clinically diagnosed FH, including probands and their relatives who were cascade-screened. We used Cox models that were adjusted for established ASCVD risk factors to assess the association between cascade screening and major adverse cardiovascular events (MACE). The median period of follow-up was 12.3 years (interquartile range [IQR] = 9.1–17.5 years), and MACE included death from any causes or hospitalization due to ASCVD events.

Results

During the observation period, 246 participants experienced MACE. The mean age of patients identified through cascade screening was 18-years younger than that of the probands (38.7 yr vs. 57.0 yr, P<0.001), with a lower proportion of ASCVD risk factors. Interestingly, patients identified through cascade screening under milder lipid-lowering therapies were at reduced risk for MACE (hazard ratio [HR] = 0.36; 95% CI = 0.22 to 0.60; P<0.001) when compared with the probands, even after adjusting for those known risk factors.

Conclusions

The identification of patients with FH via cascade screening appeared to result in better prognoses.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Scientific research grants from the Ministry of Education, Science and Culture of Japan (no. 16K19394, 18K08064, and 19K08575)

Recurrence of atrial fibrillation after catheter ablation is associated with major adverse cardiac and cerebrovascular events: insights from AF frontier ablation registry

Background

Recent observational studies have suggested that catheter ablation for atrial fibrillation (AF) is significantly associated with reduced risk for stroke, cardiovascular events and all-cause death. However, little is known whether late recurrence of AF after catheter ablation is associated with worse clinical outcomes.

Purpose

We aimed to clarify whether late recurrence of AF after catheter ablation is associated with major adverse cardiac and cerebrovascular events (MACCE).

Methods

We retrospectively investigated 2,737 participants (74.4% men, mean age 63.4±10.3 years, 62.7% paroxysmal AF) who received first catheter ablation for AF and completed follow-up more than 3 months after the procedure from AF Frontier Ablation Registry, a multicenter cohort study in Japan. We evaluated an association between late recurrence of AF after catheter ablation and first MACCE in cox-regression hazard models adjusted for known risk factors. MACCE were defined as stroke/transient ischemic attack (TIA), cardiovascular events or all-cause death. Late recurrence was defined as AF relapse more than 3 months after the procedure.

Results

During a mean follow-up period of 25.2 months, 2,070 patients (75.6%) were free from AF after catheter ablation and 122 patients (4.5%) had MACCE (ischemic stroke 18 [14.8%], hemorrhagic stroke 16 [13.1%], TIA 7 [5.7%], hospitalization for heart failure 19 [15.6%], acute coronary syndrome 19 [15.6%], hospitalization for other cardiovascular events 24 [20%] and all-cause death 19 [15.6%]). The MACCE occurred significantly more frequently in the recurrence group than in non-recurrence group (7.5% vs. 3.5%; hazard ratio [HR] 1.85; 95% confidence interval [CI] 1.28–2.65; P=0.001) (Figure). Multivariate analysis revealed that baseline age (HR 1.05; 95% CI 1.03–1.08; P<0.001), heart failure (HR 1.76; 95% CI 1.17–2.66; P=0.007), old myocardial infarction (HR 4.49; 95% CI 2.59–7.81; P<0.001), non-ischemic cardiomyopathy (HR 2.56; 95% CI 1.47–4.46; P=0.001), left atrial diameter (HR 1.22 per 5-mm increase; 95% CI, 1.06–1.41; P=0.006) and recurrence of AF (HR 1.69; 95% CI 1.17–2.44; P=0.005) were independently associated with the incidence of MACCE after catheter ablation.

Conclusion

In the Japanese multicenter cohort of AF ablation, late recurrence of AF was independently associated with increased MACCE, suggesting the significance of sinus rhythm maintenance by catheter ablation.

Kaplan-Meier curves for MACCE

Funding Acknowledgement

Type of funding source: None

B-Type natriuretic peptide predicts major adverse cardiac and cerebrovascular events after catheter ablation of atrial fibrillation: insights from AF frontier ablation registry

Background

High plasma B-Type natriuretic peptide (BNP) level is associated with cardiac events or stroke in patients with atrial fibrillation (AF). However, it is still unknown whether BNP predicts worse clinical outcomes after catheter ablation ofAF.

Purpose

We aimed to see if plasma BNP level is associated with major adverse cardiac and cerebrovascular events (MACCE) after catheter ablation of AF.

Methods

We retrospectively analyzed 1,853 participants (73.1% men, mean age 63.3±10.3 years, 60.7% paroxysmal AF) who received first catheter ablation of AF with pre-ablation plasma BNP level measurement and completed follow-up more than 3 months after the procedure from AF Frontier Ablation Registry, a multicenter cohort study in Japan. We evaluated an association between plasma BNP level before catheter ablation and first MACCE in cox-regression hazard models adjusted for known risk factors. MACCE were defined as stroke/transient ischemic attack (TIA), cardiovascular events or all-cause death.

Results

The mean plasma BNP level was 120.2±3.7 pg/mL. During a mean follow-up period of 21.9 months, 57 patients (3.1%) suffered MACCE (ischemic stroke 8 [14.0%], hemorrhagic stroke 5 [8.8%], TIA 5 [8.8%], hospitalization for heart failure 11 [19.2%], acute coronary syndrome 9 [15.8%], hospitalization for other cardiovascular events 8 [14.0%] and all-cause death 11 [19.2%]). Plasma BNP level of patients with MACCE were significantly higher than those without MACCE (291.7±47.0 vs 114.7±3.42 pg/mL, P<0.001). Multivariate analysis revealed that plasma BNP level (hazard ratio [HR] per 10 pg/mL increase 1.014; 95% confidence interval [CI] 1.005–1.023; P=0.001), baseline age (HR 1.052; 95% CI 1.022–1.084; P=0.001), heart failure (HR 2.698; 95% CI 1.512–4.815; P=0.001), old myocardial infarction (HR 3.593; 95% CI 1.675–7.708; P=0.001) and non-ischemic cardiomyopathy (HR 2.676; 95% CI 1.337 - 5.355; P=0.005) were independently associated with MACCE. At receiver-operating characteristic curve analysis, plasma BNP level before catheter ablation ≥162.7 pg/mL was the best threshold to predict MACCE (area under the curve: 0.71). Kaplan-Meier curve analysis (Figure) showed that the cumulative incidence of MACCE was significantly higher in patients with a BNP ≥162.7 pg/mL than in those with a BNP below 162.7 pg/mL (HR 4.85; 95% CI 2.86–8.21; P<0.001).

Conclusions

Elevation of plasma BNP level was independently related to the increased risk of MACCE after catheter ablation ofAF.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Bristol-Meiers Squibb

Effects of PCSK9 inhibitor on adverse limb outcomes in patients with critical limb ischemia

Background

The proprotein convertase subtilisin/kexin type 9 inhibitor (PCSK9-I), evolocumab, reduced the risk of cardiovascular event in patients with peripheral artery disease in FOURIER trial. However, the effects of evolocumab on favorable limb outcomes in patients with critical limb ischemia (CLI) is still unclear.

Purpose

The aim of this study was to evaluate the impacts of evolocumab on favorable limb outcomes and lipid profile in patients with CLI.

Methods

This was a single center, prospective observational study. A total of 39 patients with CLI were enrolled between November 2016 to May 2019. The subjects were divided into 2 groups based on evolocumab administration: evolocumab-treated group: E group (mean 69.4±11.7 years, n=14) and evolocumab non-treated group: Non-E group (mean 74.0±8.8 years, n=25). Baseline characteristics were assessed at admission. Lipid profile was evaluated at admission, 1, 3, 6, 12 and 18 months. The primary outcome was defined 18-month amputation-free survival (AFS). The secondary outcomes were defined 18-month overall survival (OS) and wound-free limb salvage. Mean follow-up period was 18±11 months.

Results

The patients in E group had greater reduction in levels of LDL cholesterol and non-HDL cholesterol than those in Non-E group over time. The reduction in MDA-LDL level was maintained at 1, 3, 6, 12 months, respectively. The 18-month AFS rate in the E-group was significantly higher than those in the Non-E group (log-rank p=0.02). The patients receiving evolocumab had a lower hazard regarding AFS (hazard ratio, 0.12; 95% confidence interval, 0.02–0.94; P=0.043) and a higher proportion of wound-free limb salvage at 12 months (E group [92%] vs Non-E group [57%], P=0.034) and 18 months (92% vs 52%, P=0.03). Otherwise, evolocumab administration was not associated with 18-month OS (log-rank p=0.053).

Conclusions

Evolocumab administration may be associated with the favorable outcome of 18-month AFS in the patients with CLI. Additionally, long-term administration of evolocumab over 12 months may improve wound-free limb salvage.

Effects of evolocumab on limb outcomes

Funding Acknowledgement

Type of funding source: None

Assessment of transporter-mediated efflux of nintedanib using in vitro cell line models of idiopathic pulmonary fibrosis

Objective: We aimed to investigate the involvement of efflux transporters, including multidrug resistant protein 1 (MDR1), multidrug resistance-associated protein 1 (MRP1), MRP2, and breast cancer resistance protein (BCRP), in the intracellular accumulation of the antifibrotic agent nintedanib in fibrotic lung cells. Methods: We used transforming growth factor-β₁ (TGF-β₁)-treated human lung fibroblasts (WI-38) and alveolar epithelial cells (A549) as in vitro models. The expression and activities of efflux transporters in TGF-β₁-treated WI-38 and A549 cells were evaluated using immunoblotting and flow cytometry. Cells were treated with nintedanib and then incubated with inhibitors of these transporters. The intracellular concentration of nintedanib was determined. Results: MDR1, MRP1, MRP2, and BCRP were found to be expressed in WI-38 and A549 cells with or without TGF-β₁ stimulation, with the exception of MRP2 in WI-38 cells. The efflux activities of these transporters were observed in these cells. MDR1 inhibitors significantly increased the intracellular accumulation of nintedanib, whereas MRP inhibitors did not show an effect. The BCRP inhibitor significantly increased the transporter activity in A549 cells but not in WI-38 cells. Conclusion: This study suggests that the efflux via MDR1 and BCRP is involved in the intracellular accumulation of nintedanib in fibrotic lung cells.

P6201Beneficial effect of ezetimibe-atorvastatin combination therapy in patients with a mutation in ABCG5 or ABCG8 gene

Background

Use of ezetimibe on top of statin therapy has been shown to be effective to reduce LDL cholesterol level in hypercholesterolemic patients. However, little is known regarding the individual variety of the effectiveness of ezetimibe. We hypothesized that hypercholesterolemic patients with a mutation in ABCG5 or ABCG8 gene exhibit better response to ezetimibe that those without, based on the fact that ezetimibe is hyper-effective for in patients with sitosterolemia caused by ABCG5 or ABCG8 genetic mutations.

Methods

Electronical medical record were reviewed in a total of 321 hypercholesterolemic patients (baseline LDL cholesterol = 192±46 mg/dl) prescribed ezetimibe 10 mg daily on top of atorvastatin 10mg daily who had undergone genetic analysis of ABCG5 or ABCG8 gene in our institute since 2006 to 2017. Pathogenicity of the variants were determined using standard variant filtering schema, including minor allele frequency, in silico annotation tools. Patients were divided into 2 groups based on the presence of ABCG5 or ABCG8 mutation. We compared the percent reduction of LDL cholesterol as well as the achieved LDL cholesterol levels between these 2 groups.

Results

We found 26 (8%) individuals who exhibit deleterious mutations in ABCG5 or ABCG8 gene. Baseline characteristics under the atorvastatin 10mg therapy were comparable in age, gender, and LDL cholesterol level between 2 groups. Under these conditions, percent reduction of LDL cholesterol in mutation positive group was significantly larger than that of mutation negative group (28±16% vs. 39±21%, p<0.05). As a result, the achieved LDL cholesterol level in mutation positive group was significantly lower than that of mutation negative group (87±29 mg/dl vs. 72±26% mg/dl, p<0.05).

Conclusion

These results suggest that ezetimibe-atorvastatin combination therapy might be more beneficial in hypercholesterolemic patients with a mutation in ABCG5 or ABCG8 gene.

3073Leveraging transcriptome sequencing for detecting novel disease-related pathways using human cardiac sarcoidosis myocardium biopsies

Background/Introduction

Cardiac sarcoidosis (CS) is one of the main causes of poor outcomes in patients with sarcoidosis, a systemic granulomatous disorder of complex etiology including a genetically susceptible host and specific exposure to disease-triggering antigens. Recently, transcriptome analysis using sarcoidosis peripheral monocytes was reported to be useful for exploring genetic susceptibility and novel disease-causing pathways. However, transcriptome sequencing has not been used to explore disease-related genes and pathways directly using human CS myocardial biopsies.

Purpose

This study aimed to identify transcriptome profiles and novel disease-related pathways of CS by comparing human CS myocardial biopsies with control samples using ribonucleic acid (RNA) sequencing (RNA-Seq).

Methods

We assessed 30 patients with suspected myocardial disorders who underwent transcatheter endomyocardial biopsies at our University Hospital, Japan. Of those, 7 were clinically diagnosed with CS, 9 with hypertrophic cardiomyopathy (HCM), and 14 with dilated cardiomyopathy (DCM). Messenger RNAs were extracted from cardiac muscle biopsies using the Ovation SoLo RNA-Seq System (NuGEN Technologies), according to the manufacturer's instructions. Sequencing was performed with coverage of approximately 20 million reads per sample using Illumina HiSeq 2000. Sequencing reads were mapped using the STAR 2-pass method with GRCh37 as the reference. The DESeq2 R package (version 3.8) was used for further analyses. Principal component analysis (PCA) on gene expression was conducted for detecting outliers such as non-muscular samples. Differential gene expression analysis was performed between the 7 patients with CS and 23 patients with cardiomyopathy (HCM and DCM, non-CS). Gene Ontology (GO) enrichment analysis was conducted to estimate possible disease-related pathways.

Results

We successfully sequenced 60 myocardial biopsy samples (original and biological duplicates) from 30 CS patients. Of these, 2 outlier samples shown by the PCA plot were removed, and 58 were used for further analyses. We found 243 genes that were differentially expressed between CS patients and non-CS patients. Top-rated genes were RP11–366M4.8, RELN, S100A6, WASF3and UCHL1. Pathway analysis using GO demonstrated enrichment oflymphocyte activation (P=4.8x10–16), organelle fission (P=6.1x10–14), the M phase of the mitotic cell cycle (P=2.2x10–13), nuclear division (P=2.4x10–13), mitosis (P=2.4x10–13) and T-cell activation pathways (P=1.2x10–12).

Conclusions

Our differential gene expression and pathway analysis results using human CS myocardial biopsies suggested that lymphocyte activation, specifically the T-cell activation pathway, is linked to CS pathogenesis. Further studies are needed to decipher the role of specific genes related to genetic susceptibility and/or pathways associated with CS occurrence.

P6202Serum sitosterol levels and ABCG5 and ABCG8 genetic mutations among Japanese dyslipidemic subjects

Background

Sitosterolemia, which is caused by ABCG5 or ABCG8 genetic mutations, is involved with marked increased concentrations of cholesterol as well as non-cholesterol plant sterols including sitosterol. Assessments of serum sitosterol level is critical to discriminate this disease from familial hypercholesterolemia (FH), which exhibits similar phenotypes except for elevated sitosterol levels. However, no prior data exist regarding the optimal cutoff value of serum sitosterol predicting the presence of sitosterolemia with double pathogenic mutations in ABCG5 or ABCG8 genes.

Methods

We retrospectively investigated consecutive 253 Japanese dyslipidemic subjects (mean age = 47.02 yr, male = 48.6%) with the assessments of serum sitosterol level as well as the presence of ABCG5 or ABCG8 genetic mutations in our institute since 2009 to 2018. Exome lesions of those 2 genes were sequenced, and pathogenicity of the identified genetic variants were determined using standard variant filtering schema, including minor allele frequency, in silico annotation tools. We divided the subjects into 3 groups based on the number of pathogenic mutations in ABCG5 or ABCG8 genes. We compared serum lipid values, including LDL cholesterol as well as serum sitosterol among those groups, and tried to determine the optimal cutoff value discriminating patients of sitosterolemia with double mutations from others.

Results

We identified 11 individuals with sitosterolemia with double mutations, 27 individuals with a single mutation, and 215 individuals without any mutations. Distribution of serum sitosterol exhibited skewed to the right (Figure). There was no significant correlation between serum sitosterol and other lipids, including LDL cholesterol. As expected, serum sitosterol level of patients with sitosterolemia exhibited significantly higher than those of any other groups (52.0 vs. 7.9 μg/ml, p=2.22×10–6, 52.0 vs. 2.8 μg/ml, p=2.275×10–8). 15 μg/ml was the optimal cut-off value, the sensitivity and specificity of which were 100%, and 99.6%, respectively.

Histgram of serum sitosterol

Conclusion

We suggest the cutoff sitosterol value of 15 μg/ml predicting the presence of sitosterolemia with double pathogenic ABCG5 or ABCG8 genetic mutations.

P5641Impact of lethal arrhythmias on medical castration in patients with prostate cancer

Background

Prostate cancer is the most common non-cutaneous malignancy in men and has been steadily rising in an aging society. Medical castration had been widely applied as a treatment for prostate cancer. Sex steroid hormones regulate cardiac ion channels. However, the proarrhythmic properties of medical castration have not been reported.

Methods

This prospective observational study consisted of 149 patients (75±6 years) who underwent hormonal therapy using gonadotropin-releasing hormone with or without anti-androgen for prostate cancer. The changes of electrocardiogram (ECG) findings during the therapy and the associations of ECG findings with lethal arrhythmias were studied.

Results

QT (394±32 to 406±39 ms, p<0.001) and QTc intervals (416±27 to 439±31 ms, p<0.001) significantly prolonged during the therapy as compared to baseline. Heart rate significantly increased during the therapy as compared to baseline (68±11 to 71±14 / min, p=0.006). PQ interval and QRS duration were similar before and during the therapy. During the hormonal therapy, 2 patients (1.3%) presented with torsades de pointes and ventricular fibrillation. The first patient was 71 year-old and the second patient was 70 year-old. The period of the therapy was 6 and 45 months, respectively. Both patients had no structural heart disease. The magnitude of QTc interval change during the therapy as compared to baseline (Δ QTc interval) was significantly greater in patients with VF than those without (p<0.001), however the magnitude of Δ heart rate, Δ PQ interval, and Δ QRS duration were similar between the 2 groups.

Conclusions

Medical castration significantly prolonged QT/QTc interval and could be a trigger of lethal arrhythmias in patients with prostate cancer.

P649Validation of clinical diagnostic criteria of familial hypercholesterolemia in Japan: evidence from a comprehensive genetic analysis

Background

Although awareness of familial hypercholesterolemia (FH) is increasing, this common, potentially fatal, treatable condition remains underdiagnosed. Japanese clinical diagnostic criteria of FH include LDL cholesterol level ≥180 mg/dl, Achilles tendon thickness (ATT) ≥9.0 mm, and family history of FH or premature coronary disease. Despite FH being a genetic disorder, genetic testing is rarely used, few data exist regarding the validation of those criteria, especially, by studies using comprehensive genetic analyses.

Methods

This study included 680 subjects (344 men, mean LDL cholesterol = 175 mg/dl) who underwent the full assessments for FH, including LDL cholesterol measurement, Achilles tendon X-ray, investigations for family history, and comprehensive genetic analyses on FH-associated genes (LDL receptor, PCSK9, APOB, and LDLRAP1) in our University Hospital since 2006 to 2018. The area under curve (AUCs) of receiver-operating characteristic (ROC) curve analyses predicting FH-mutation positive were compared among those determined by each component.

Results

ROC analyses revealed the optimal cutoff LDL cholesterol value for predicting the presence of FH-mutation was 181 mg/dl, and that of ATT was ≥7.0 mm. AUCs of each component (ATT, LDL cholesterol, and family history) were 0.827, 0.889, and 0.906, respectively, and the combination of all components increased it to 0.975. When adopting ATT ≥7.0 mm as one of the clinical diagnostic criteria, 13 individuals (2%) were newly classified as true-FH, whereas, 27 (4%) individuals were newly misclassified as FH.

Conclusion

The current Japanese clinical diagnostic criteria of FH were pretty well validated in our independent cohort. However, the threshold of ATT could be lowered to 7.0 mm to raise the sensitivity of its criteria.

P6339Sequential organ failure assessment score on admission predicts long-time mortality of the patients with acute heart failure

Background

Despite the remarkable advances in the treatment options of acute heart failure (HF), prognosis assessment remains an ongoing challenge. Previous studies revealed only a moderate accuracy of models predicting mortality. Sequential Organ Failure Assessment (SOFA) Score are widely used in the intensive care unit (ICU) to predict outcome and predicted higher long-time mortality in unselected patients in cardiac ICU. In addition, the American Heart Association Get With the Guidelines–Heart Failure (GWTG-HF) risk score allows for risk stratification of 30-day outcome for patients hospitalized with HF. The purpose of this study was to evaluate whether SOFA score on admission is useful for long-time mortality prediction in acute HF patients and also to assess the discriminative performance as compared with GWTG-HF risk score.

Methods

This was a single-centre, retrospective cohort study. Between January 2007 and December 2016, we screened eligible 661 consecutive patients with acute HF administered at our hospital. SOFA score on admission of 294 patients was able to calculate retrospectively. We enrolled 269 patients who could complete follow up evaluation for more than 1 year. Endpoint was all-cause mortality after admission. Additive information of SOFA score was evaluated by area under the curve (AUC), net reclassification improvement (NRI), integrated discrimination improvement (IDI) and decision curve analysis (DCA).

Results

The 269 patients were included in this study (78.5±10.9 years; 136 men; left ventricular ejection fraction [EF], 49.8±16.6%) during a mean follow-up of 32.1±22.3 months. Patients with all-cause death had higher SOFA score (4.2±2.3 versus 2.8±1.8, p<0.001; AUC, 0.689) and GWTG-HF risk score (44.0±7.6 versus 38.1±7.9, P<0.001, AUC, 0.692).

Kaplan-Meier survival analysis demonstrated higher SOFA scores (P<0.001) and GWTG-HF risk scores (P<0.001) appears to be related to increase probabilities of all cause death. A multivariate Cox proportional hazard model were made with adjustment for SOFA score, GWTG-HF risk score, age, gender and ejection fraction. As a result, SOFA score (hazard ratio [HR] 1.227; 95% confidence interval [CI], 1.130 to 1.326; P<0.001), GWTG-HF (HR, 1.054; 95% CI, 1.029 to 1.078; P<0.001) and age (HR, 1.069; 95% CI 1.048 to 1.092; P<0.001) were independent predictors of all cause death and HR of SOFA score was the highest in these parameters. Incorporating SOFA score into GWTG-HF score yielded a significant NRI (0.528 (95% CI 0.291 to 0.765) and IDI (0.046 (95% CI 0.020 to 0.072). In DCA, compared with the reference model, the net benefit for SOFA score model was greater across the range of threshold probabilities.

Conclusions

The SOFA score, simple and validated mortality risk score can predict long-term all-cause mortality in patients with acute HF. Discriminative performance metrics such as NRI, IDI and DCA were improved on incorporation of the SOFA score for prediction of mortality.

P6199Lipoprotein(a) and risk of chronic kidney disease among 4,235 Japanese hospitalized patients

Background

Lipoprotein (a) [Lp(a)] has been shown to be associated with the development of chronic kidney disease (CKD) among various ethnicities. In addition, recent Mendelian randomization studies have suggested that Lp(a) seems to be causally associated with CKD. However, few data exist regarding this issue among Japanese population.

Purpose

We aimed to investigate the association between serum Lp(a) and the CKD among Japanese population.

Methods

We retrospectively investigated 6,130 subjects whose serum Lp(a) had been measured for any reason (e.g. any operations which needs bed rest for a long duration, risk factors for atherosclerosis such as hypertension or diabetes) at our University Hospital from April 2004 to March 2014. We excluded 1,895 subjects due to the lack clinical data. We assessed their Lp(a), LDL cholesterol, HDL cholesterol, triglycerides, presence of hypertension, diabetes, chronic kidney disease, smoking, body mass index, presence of coronary artery disease (CAD), and presence of CKD (stage 3 or greater).

Results

When the study subjects were divided into 5 groups based on their CKD stage, there was a significant trend among their serum Lp(a) levels (P-trend = 2.7×10–13). Under these conditions, multiple regression analysis showed that Lp(a) was significantly associated with CKD [odds ratio (OR): 1.12, 95% confidence interval (CI): 1.08–1.17; p=1.3×10–7: per 10mg/dL)., independent of other classical risk factors, including age, gender, body mass index, hypertension, diabetes, smoking, LDL cholesterol and triglycerides. Under these conditions, Lp(a) was significantly associated with CAD [OR: 1.11, 95% CI: 1.06–1.16; p=1.7×10–6: per 10mg/dL), independent of the presence of CKD.

Conclusion

Serum Lp(a) was associated with the development of CKD independent of other classical risk factors among Japanese population as well.

P1535Clinical impact of carotid plaque score rather than carotid intima-media thickness on atherosclerotic cardiovascular disease

Background

Carotid intima-media thickness (cIMT) assessed by ultrasound has been widely accepted as a surrogate marker of atherosclerotic cardiovascular disease. On the other hand, carotid plaque score (cPS) reflecting throughout the carotid artery plaque burden may be better marker.

Methods

We retrospectively examined 2,035 patients who underwent carotid ultrasonography between January 2006 and December 2015 at our University Hospital. Median follow-up period was 4 years. We used Cox models that adjusted for established risk factors of ASCVD, including age, gender, hypertension, diabetes, smoking, and serum lipids to assess the association of cIMT as well as cPS with major adverse cardiac events (MACE). MACE was defined as all-cause mortality or rehospitalization for a cardiovascular-related illness

Results

During follow-up, 243 participants experienced MACE. After adjustment for established risk factors, cPS was associated with MACE (hazard ratio [HR] = 3.38 for top quintile vs. bottom quintile of cPS; 95% confidence interval [CI] 1.82 to 6.27; P-trend = 1.4×10–8), while cIMT was not (HR = 0.88, P=0.57). Addition of the cPS to established risk factors significantly improved risk discrimination (C-index 0.726 vs. 0.746; P=0.017)

Conclusion

As a marker, cPS, rather than cIMT can identify 20% of individuals who are at more than three-fold increased risk for MACE. Targeting diagnostic or therapeutic interventions to this subset may prove clinically useful.

Augmentation of Lipopolysaccharide-Induced Production of IL-1α and IL-1β in Mice Given Intravenous Zoledronate (a Nitrogen-Containing Bisphosphonate) and Its Prevention by Clodronate (a Non-nitrogen-containing Bisphosphonate)

Bisphosphonates (BPs) bind strongly to bone and exhibit long-acting anti-bone-resorptive effects. Among BPs, nitrogen-containing BPs (N-BPs) have far stronger anti-bone-resorptive effects than non-N-BPs. However, N-BPs induce acute inflammatory reactions (fever, arthralgia and myalgia, etc.) after their first injection. The mechanisms underlying these side effects remain unclear. Zoledronate (one of the most potent N-BPs) is given intravenously to patients, and the side-effect incidence is reportedly the highest among N-BPs. Our murine experiments have clarified that (a) intraperitoneally injected N-BPs induce various inflammatory reactions, including a production of interleukin-1 (IL-1) (a typical inflammatory cytokine), and these inflammatory reactions are weak in IL-1-deficient mice, (b) subcutaneously injected N-BPs induce inflammation/necrosis at the injection site, (c) lipopolysaccharide (LPS; a cell-wall component of Gram-negative bacteria) and N-BPs mutually augment their inflammatory/necrotic effects, (d) the non-N-BP clodronate can reduce N-BPs' inflammatory/necrotic effects. However, there are few animal studies on the side effects of intravenously injected N-BPs. Here, we found in mice that (i) intravenous zoledronate exhibited weaker inflammatory effects than intraperitoneal zoledronate, (ii) in mice given intravenous zoledronate, LPS-induced production of IL-1α and IL-1β was augmented in various tissues, including bone, resulting in them increasing in serum, and (iii) clodronate (given together with zoledronate) prevented such augmentation and enhanced, slightly but significantly, zoledronate's anti-bone-resorptive effect. These results suggest that infection may be a factor promoting the acute inflammatory side effects of N-BPs via augmented production of IL-1 in various tissues (including bone), and that clodronate may be useful to reduce or prevent such side effects.

Cyclic Stretch Force Induces Periodontal Ligament Cells to Secrete Exosomes That Suppress IL-1β Production Through the Inhibition of the NF-κB Signaling Pathway in Macrophages

In the oral mechanical environment, periodontal ligament cells (PDL cells) contribute to maintaining periodontal tissue homeostasis. Recent studies showed that exosomes, which are small vesicles secreted by various types of cells, play a pivotal role in cell-to-cell communication in biological processes. We examined the secretion of exosomes from PDL cells stimulated with cyclic stretch and their role in the inflammatory response of macrophages using the human macrophage cell line THP-1 and human primary monocytes/macrophages. We prepared supernatants from human PDL cells (PDL-sup) stimulated with cyclic stretch. The treatment of macrophages with PDL-sup, but not PDL-sup from unstimulated PDL cells, inhibited the production of IL-1β in LPS/nigericin-stimulated macrophages. The pretreatment of PDL cells with GW4869, an inhibitor of exosome secretion, or siRNA for Rab27B, which controls exosome secretion, abrogated the inhibitory effects of PDL-sup. A transmission electron microscopy analysis demonstrated the existence of exosomes with diameters ranging between 30 and 100 nm in PDL-sup, suggesting that exosomes in PDL-sup contribute to this inhibition. An immunofluorescence microscopy analysis revealed that exosomes labeled with PKH67, a fluorescent dye, were incorporated by macrophages as early as 2 h after the addition of exosomes. Purified exosomes inhibited IL-1β production in LPS/nigericin-stimulated macrophages and the nuclear translocation of NF-κB as well as NF-κB p65 DNA-binding activity in LPS-stimulated macrophages, suggesting that exosomes suppress IL-1β production by inhibiting the NF-κB signaling pathway. Our results indicate that PDL cells in mechanical environments contribute to the maintenance of periodontal immune/inflammatory homeostasis by releasing exosomes.

Abstract OT2-07-05: A phase III trial to compare eribulin mesylate + trastuzumab (H) + pertuzumab (P) with paclitaxel or docetaxel + HP for HER2-positive advanced or metastatic breast cancer (JBCRG-M06/ EMERALD)

Background: Docetaxel + Trastuzumab (H) + Pertuzumab (P) provided progression-free survival (PFS) and overall survival (OS) benefits in HER2-positive advanced or metastatic breast cancer (AMBC) in the CLEOPATRA study as a first-line therapy. However, long-term administration of docetaxel at a dose of 75 mg/m2 every 3 weeks in AMBC patients (pts) is difficult due to the toxicities. Eribulin mesylate (E) is a well-tolerated microtubule inhibitor, and we have reported the efficacy and safety of EHP regimen as first- and second-line therapy for AMBC in a multicenter, phase II study (JBCRG-M03/UMIN000012232). In this M06 study, we address the clinical question as to which is the better chemotherapy partner for HP as first line regimen, in terms of efficacy, toxicity and QOL.

Methods: JBCRG-M06 is a multicenter open-label randomized phase III study for HER2-positive AMBC pts who have received no prior chemotherapy except for the HER2- Antibody-Drug Conjugate (ADC). Pts will be randomized 1:1 to E (1.4mg/m2 on day 1 and 8) + H (8 mg/kg loading dose followed by 6 mg/kg) +P (840 mg loading dose followed by 420 mg) q3wks or standard taxanes (docetaxel 75mg/m2 on day1 or paclitaxel 80mg/m2 on day 1, 8 and 15) + HP q3wks. Stratification factors for randomization are; presence of visceral metastases, number of prior taxanes on perioperative adjuvant treatment, and treatment with prior anti-HER2-ADC. Primary endpoint is PFS and secondary endpoints include overall response rate, duration of response, OS, patient-reported outcomes (PRO) relating to QOL and peripheral neuropathy, new-metastases free survival, and safety. Translational research to search for biomarker for individual precision therapy will be performed. Main eligibility criteria are as follows: pts with HER2-positive AMBC, female aged 20-70 years old, ECOG PS of 0-1, LVEF ≥ 50% at baseline and adequate organ function. Pts who had progressive MBC within 6 months after the end of primary adjuvant systemic chemotherapy are excluded. The sample size was calculated by type1 error (2-sided) of 0.05 and 80% power to estimate the noninferiority margin 1.33 with an expected median PFS of 14.2 months. The target number of pts is 480 recruited over the duration of 3-years. The first patient in was achieved on August 2017. (ClinicalTrials.gov Identifier:NCT03264547).

Citation Format: Masuda N, Yamashita T, Saji S, Araki K, Ito Y, Takano T, Takahashi M, Tsurutani J, Koizumi K, Kitada M, Kojima Y, Sagara Y, Tada H, Iwasa T, Kadoya T, Iwatani T, Hasegawa H, Morita S, Ohno S. A phase III trial to compare eribulin mesylate + trastuzumab (H) + pertuzumab (P) with paclitaxel or docetaxel + HP for HER2-positive advanced or metastatic breast cancer (JBCRG-M06/ EMERALD) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-07-05.

Nicotine exposure induces the proliferation of oral cancer cells through the α7 subunit of the nicotinic acetylcholine receptor

Oral cancer and smoking are closely related, because the oral cavity, which is the route of ingestion of tobacco smoke, is in direct contact with the oral mucosa. Nicotine, one of the components of tobacco, can diffuse rapidly to the central nervous system and is responsible for tobacco addiction. Nicotine is present in high concentrations in the bloodstream of smokers; while the addictive effects of this alkaloid have extensively been studied, its effect on tumorigenesis is not clear yet. Therefore, in this study, we examined the effect of nicotine on cell proliferation and the signaling pathways it activates. The human oral squamous cell carcinoma cell line HSC-2 was used as a model system. We demonstrated the correlation between nicotine and epidermal growth factor receptor (EGFR) signaling. Nicotine treatment induced HSC-2 cell proliferation and migration and the phosphorylation of EGFR. Furthermore, nicotine treatment activated the EGFR downstream effectors phosphatidylinositol-3 kinase/AKT and p44/42 mitogen-activated protein kinases (ERK), which, in turn, promoted cell proliferation. Overall, our study suggests that nicotine promotes cell growth and migration through epidermal growth factor (EGF) signaling and plays an important role in oral cancer progression.

Dectin-2-Mediated Signaling Leads to Delayed Skin Wound Healing through Enhanced Neutrophilic Inflammatory Response and Neutrophil Extracellular Trap Formation

Dendritic cell-associated C-type lectin-2 (i.e., dectin-2) recognizes fungal polysaccharides, including α-mannan. Dectin-2-mediated recognition of fungi, such as Candida albicans, leads to NF-κB activation, which induces production of inflammatory cytokines. However, the role of dectin-2 in skin wound healing remains unclear. In this study, we sought to determine how dectin-2 deficiency and the administration of α-mannan affected the wound healing process. Full-thickness wounds were created on the backs of wild type C57BL/6 and dectin-2-deficient mice. We analyzed wound closure, histological findings, and re-epithelialization. We also examined the neutrophilic inflammatory responses and neutrophil extracellular trap (NET)-osis at the wound sites after administration of α-mannan. The percent wound closure and re-epithelialization was significantly accelerated in dectin-2-knockout mice compared with wild-type mice on days 3 and 5 after wounding. In contrast, administration of α-mannan delayed wound closure in wild-type mice, and these responses were canceled in dectin-2-knockout mice. Furthermore, mice administered α-mannan, neutrophil infiltration was prolonged, and the expression of citrullinated histone, an indicator of NETosis, at the wound sites was accelerated. Administration of a neutrophil elastase inhibitor significantly improved the delayed wound healing caused by α-mannan. These results suggest that dectin-2 may have a deep impact on the skin wound healing process through regulation of neutrophilic responses.

MrgX2‑mediated internalization of LL‑37 and degranulation of human LAD2 mast cells

LL‑37 is the sole antimicrobial peptide of human cathelicidin comprising 37 amino acids, which is expressed mainly in epithelial cells and neutrophils, and activates mast cells. In the present study, in order to elucidate the mechanism of mast cell activation by LL‑37, the associations between the internalization of LL‑37 and Mas‑related gene X2 (MrgX2)‑mediated mast cell activation (degranulation) was investigated using the human mast cell line, LAD2. LL‑37 was rapidly internalized into the cells, and induced degranulation, as assessed by the extracellular release of β‑hexosaminidase. Pertussis toxin, a G‑protein inhibitor, significantly suppressed the internalization of LL‑37 and the degranulation of LAD2 cells. Furthermore, small interfering (si)‑RNA‑mediated knockdown of MrgX2, a putative G protein‑coupled receptor for LL‑37, inhibited the internalization of LL‑37 and degranulation of LAD2 cells. Notably, LL‑37 internalization was enhanced by the stable expression of MrgX2 in HMC‑1 and 293 cells. In addition, the internalized LL‑37 mainly colocalized with MrgX2 in the perinuclear region of LAD2 cells. Furthermore, neuraminidase treatment, which removes negatively charged sialic acid from the cell surface, markedly reduced the internalization of LL‑37 and degranulation of LAD2 cells, and clathrin‑mediated endocytosis inhibitors (dynasore and chlorpromazine) inhibited the internalization and degranulation of LAD2 cells. Taken together, these observations indicated that LL‑37 may bind the negatively charged cell surface molecules, rapidly internalize into the cells via clathrin‑mediated endocytosis and interact with MrgX2 to activate mast cells (LAD2 cells).

Cyclic Stretch Negatively Regulates IL-1β Secretion Through the Inhibition of NLRP3 Inflammasome Activation by Attenuating the AMP Kinase Pathway

Macrophages are immune cells of hematopoietic origin that play diverse roles in host defenses and tissue homeostasis. In mechanical microenvironments, macrophages receive mechanical signals that regulate various cellular functions. However, the mechanisms by which mechanical signals influence the phenotype and function of macrophages in the process of inflammation have not yet been elucidated in detail. We herein examined the effects of cyclic stretch (CS) on NLR family, pyrin domain-containing 3 (NLRP3) inflammasome activation in J774.1, a murine macrophage cell line, and mouse primary bone marrow-derived macrophages. We showed that cyclic stretch inhibited adenosine triphosphate (ATP)-stimulated interleukin (IL)-1β secretion in lipopolysaccharide (LPS)-primed macrophages using ELISA and Western blot analyses. Cyclic stretch did not affect the degradation of the Inhibitor of κB or the nuclear translocation/transcriptional activity of nuclear factor (NF)-κB, suggesting that cyclic stretch-mediated inhibition was independent of the NF-κB signaling pathway. Consistent with these results, cyclic stretch did not affect the LPS-induced expression of inflammasome components, such as pro-IL-1β and NLRP3, which is known to require the activation of NF-κB signaling. We showed that the cyclic stretch-mediated inhibition of IL-1β secretion was caused by the suppression of caspase-1 activity. The addition of compound C, a specific inhibitor of adenosine monophosphate-activated protein kinase (AMPK), to LPS-primed macrophages inhibited IL-1β secretion as well as caspase-1 activation, suggesting that AMPK signaling is involved in ATP-triggered IL-1β secretion. Furthermore, the phosphorylation of AMPK induced by ATP in LPS-primed macrophages was significantly suppressed by cyclic stretch, indicating that cyclic stretch negatively regulates IL-1β secretion through the inhibition of caspase-1 activity by attenuating the AMPK pathway. Our results suggest that mechanical stress functions to maintain homeostasis through the prevention of excessive inflammasome activation in macrophages in mechanical microenvironments.

[A Case of Intraductal Pancreatic Mallignant Tumor with Difficulty in Differentiating between IPMN and ITPN]

The patient was a male in his early 60s. Diabetes had aggravated 6 months earlier, and the patient was referred to our hospital for close examination. On contrast CT, enhanced mass shadows filling the lumen of the main pancreatic duct, which was dilated throughout the pancreas, were observed, and the mass was diagnosed as an adenocarcinoma on EUS-FNA. Based on these findings, main-duct IPMN was suspected and total pancreatectomy was performed. On macroscopic observation of the resected specimen, outgrowth of a solid tumor was observed in the main pancreatic duct, whereas only low-level mucus retention was noted in the pancreatic duct. Histopathological examination revealed a papillary/tubular tumor growth, suggesting interstitial infiltration throughout the pancreas. On immunostaining, the tumor was partially positive for MUC5AC, based on which the patient was diagnosed with an intraductal pancreatic mallignant tumor, with difficulty in differentiating between IPMC and ITPC. Clinicopathologically, many aspects regarding ITPN remain unclear. Further accumulation of such cases and investigation of the tumor pathology are necessary.