Enhanced inhibitory activity of compounds containing purine scaffolds compared to protein kinase CK2α considering crystalline water

We recently reported novel purine-based CK2α inhibitors using the solvent ordering-based method as virtual screening. Among these, the X-ray crystal structure of a complex with CK2α was determined. The results showed that the crystalline water molecules observed in many previously reported complex structures of CK2α and its inhibitors had been eliminated. We then proposed a structure-based drug design. Since the removal of water molecules would be detrimental to inhibitor binding, new groups of compounds were designed by changing the position of the carboxy group located at the point where a water molecule would be present so as not to eliminate it. Compounds with (E)-2-carboxyethenyl and 3-carboxyphenyl substituted at the 2-position on the purine scaffold showed much higher inhibitory potency than 4-carboxyphenyl derivatives. Furthermore, in the presence of a 4-fluorophenyl group at the 9-position on the purine scaffold, the inhibitory activity of the 3-carboxyphenyl derivative against CK2α was 0.18 μM, a 167-fold improvement compared to the 4-carboxyphenyl derivative. The strategy of leaving crystalline water can significantly increase inhibitory activity.

Distinct binding modes of a benzothiazole derivative confer structural bases for increasing ERK2 or p38α MAPK selectivity

Mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase 2 (ERK2) and p38α MAP kinase (p38α MAPK), regulate various cellular responses. ERK2 is a drug target for treating many diseases, such as cancer, whereas p38α has attracted much attention as a promising drug target for treating inflammatory disorders. ERK2 is a critical off-target for p38α MAPK and vice versa. In this study, an allosteric ERK2 inhibitor with a benzothiazole moiety (compound 1) displayed comparable inhibitory activity against p38α MAPK. Crystal structures of these MAPKs showed that compound 1 bound to the allosteric site of ERK2 and p38α MAPK in distinct manners. Compound 1 formed a covalent bond with Cys162 of p38α MAPK, whereas this covalent bond was absent in the ERK2 complex even though the corresponding cysteine is conserved in ERK2. Structural dissection combined with computational simulations indicated that an amino acid difference in the allosteric site is responsible for the distinct binding modes of compound 1 with ERK2 and p38α MAPK. These structural insights underline the feasibility of developing highly selective and potent ERK2 and p38α MAPK inhibitors.

Erratum: Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande [Phys. Rev. Lett. 130, 031802 (2023)]

This corrects the article DOI: 10.1103/PhysRevLett.130.031802.

Dosimetric Comparison of Nodal Clinical Target Volume for Locally Advanced Non-Small Cell Lung Cancer: Options for Geometric Expansion vs. Lymph Node Stations

PURPOSE/OBJECTIVE(S)

We investigated whether dosimetric differences existed in nodal clinical target volume (CTV) using options for geometric expansion and lymph node stations based on the European Society for Radiotherapy and Oncology (ESTRO) guideline for locally advanced non-small cell lung cancer (NSCLC).

MATERIALS/METHODS

With treatment planning computed tomographic images in 17 patients who underwent radiotherapy for cT4N2M0 NSCLC from 2017 to 2022 at our institution, we retrospectively contoured nodal CTVs based on the guideline's options of: (1) geometric expansion, CTV including the nodal gross tumor volume plus 5 mm margin: (2) lymph node stations, CTV including the affected lymph node stations. The 5 mm margins for planning target volume (PTV) were added to the nodal and primary tumors' CTVs. Treatment planning of 60 Gy in 30 fractions to the PTV D50% was performed using volumetric modulated arc therapy; Dn% was irradiated dose to n% of volume of the structure; VnGy was percentage of volume of the structure at least irradiated n Gy. We compared dose-volume parameters between the two options using Wilcoxon rank sum test.

RESULTS

Primary tumors were located in the right and left lobes in 12 and five patients, and in the upper and lower lobes in 13 and four patients, respectively. Median PTV size/D95% of the options for geometric expansion and lymph node stations were 569 cc (range, 149-2005 cc)/58.2 Gy (range, 57.5-58.7 Gy) and 635 cc (range, 184-2109 cc)/58.1 Gy (range, 57.5-58.7 Gy), respectively. Median mean dose of the esophagus/heart in the two options were 12.2 Gy (range, 6.6-24.9 Gy)/3.3 Gy (range, 0.6-19.1 Gy) and 16.1 Gy (range, 13.6-30.5 Gy)/4.6 Gy (range, 0.7-18.9 Gy), respectively. Median V20 Gy/mean dose of the lungs in the options for geometric expansion and lymph node stations were 20.5% (range, 14.8-33.9%)/12.2 Gy (range, 8.7-18.4 Gy) and 24.0% (range, 15.1-36.7%)/13.5 Gy (range, 9.5-19.4 Gy), respectively. In the eight patients (47%) with lymph node metastases in stations 2 or 3, a significant dosimetric difference between the two options existed on V20 Gy of the lungs; median values of the difference were 2.8% and 0.5% with and without lymph node metastases in stations 2 or 3, respectively (p = 0.027).

CONCLUSION

Of the ESTRO guideline for the nodal CTV, using the option for geometric expansion might be able to reduce V20 Gy of the lungs in patients with lymph node metastases in stations 2 or 3.

Low entropic cost of binding confers high selectivity on an allosteric ERK2 inhibitor

Extracellular signal-regulated kinase 2 (ERK2), a mitogen-activated protein kinase (MAPK), plays an essential role in physiological cellular processes and is a drug target for treating cancers and type 2 diabetes. A previous in silico screening study focusing on an allosteric site that plays a crucial role in substrate anchoring conferred an ERK2 inhibitor (compound 1). In this report, compound 1 was found to show high selectivity toward ERK2 compared with the nearest off-target p38α MAPK, and the crystal structure revealed that compound 1 binds to the allosteric site of ERK2. Fragment molecular orbital calculations based upon this crystal structure provided the structural basis to improve potency of compound 1 derivatives. Further computational studies uncovered that the low entropic cost of binding conferred the high selectivity of compound 1 toward ERK2 over p38α MAPK. These findings demonstrate the feasibility of developing potent and selective ERK2 inhibitors.

Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande

We report a search for cosmic-ray boosted dark matter with protons using the 0.37  megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1  MeV/c^{2} to 300  MeV/c^{2}.

Design, Synthesis and Structure-Activity Relationship Studies of Protein Kinase CK2 Inhibitors Containing a Purine Scaffold

Protein kinase CK2 (CK2) is involved in the suppression of gene expression, protein synthesis, cell proliferation, and apoptosis, thus making it a target protein for the development of therapeutics toward cancer, nephritis, and coronavirus disease 2019. Using the solvent dipole ordering-based method for virtual screening, we identified and designed new candidate CK2α inhibitors containing purine scaffolds. Virtual docking experiments supported by experimental structure-activity relationship studies identified the importance of the 4-carboxyphenyl group at the 2-position, a carboxamide group at the 6-position, and an electron-rich phenyl group at the 9-position of the purine scaffold. Docking studies based on the crystal structures of CK2α and inhibitor (PDBID: 5B0X) successfully predicted the binding mode of 4-(6-carbamoyl-8-oxo-9-phenyl-8,9-dihydro-7H-purin-2-yl) benzoic acid (11), and the results were used to design stronger small molecule targets for CK2α inhibition. Interaction energy analysis suggested that 11 bound around the hinge region without the water molecule (W1) near Trp176 and Glu81 that is frequently reported in crystal structures of CK2α inhibitor complexes. X-ray crystallographic data for 11 bound to CK2α was in very good agreement with the docking experiments, and consistent with activity. From the structure-activity relationship (SAR) studies presented here, 4-(6-Carbamoyl-9-(4-(dimethylamino)phenyl)-8-oxo-8,9-dihydro-7H-purin-2-yl) benzoic acid (12) was identified as an improved active purine-based CK2α inhibitor with an IC₅₀ of 4.3 µM. These active compounds with an unusual binding mode are expected to inspire new CK2α inhibitors and the development of therapeutics targeting CK2 inhibition.

Bivalent binding mode of an amino-pyrazole inhibitor indicates the potentials for CK2α1-selective inhibitors

Casein kinase 2 (CK2) is a vital protein kinase that consists of two catalytic subunits (CK2α1 and/or CK2α2) and two regulatory subunits (CK2β). CK2α1 is a drug target for nephritis and cancers, while CK2α2 is a serious off-target because its inhibition causes testicular toxicity. High similarity between the isozymes CK2α1 and CK2α2 make it difficult to design CK2α1-specific inhibitors. Herein, the crystal structures of CK2α1 and CK2α2 complexed with a 3-amino-pyrazole inhibitor revealed the remarkable differences in the protein-inhibitor interaction modes. This inhibitor bound to the ATP binding sites of both isozymes in apparently distinct orientations. In addition, another molecule of this inhibitor bound to CK2α1, but not to CK2α2, at the CK2β protein-protein interface. Binding energy calculations and biochemical experiments suggested that this inhibitor possesses the conventional ATP-competitive characteristics with moderate allosteric function in a molecular glue mechanism. These results will assist the potential design of potent and selective CK2α1 inhibitors.

Turbulence Spreading into an Edge Stochastic Magnetic Layer Induced by Magnetic Fluctuation and Its Impact on Divertor Heat Load

Turbulence spreading into the edge stochastic magnetic layer induced by magnetic fluctuation is observed at the sharp boundary region in the large helical device. The density fluctuation excited at the sharp boundary region with a large pressure gradient does not propagate into the boundary region due to the blocking of turbulence spreading by the large second derivative of the pressure gradient. Once the magnetic fluctuation appears at the boundary, the density fluctuation begins to penetrate the edge stochastic layer and the second derivative of the pressure gradient also decreases. The increase of density fluctuation in this layer results in the broadening and reduction of the peak divertor heat load. It is demonstrated that magnetic fluctuation plays a key role in controlling the turbulence spreading at the boundary of plasma which contributes to the reduction of divertor heat load.

Significance of mitral L wave to predict late recurrence of atrial fibrillation after radiofrequency catheter ablation

Background

Mitral L wave, prominent mid-diastolic filling wave in echocardiographic examinations, is associated with severe left ventricular diastolic dysfunction, and that has been reported to predict recurrent atrial fibrillation (AF) after cardioversion. However, association between mitral L wave and the outcome of AF after radiofrequency catheter ablation (RFCA) has not been established.

Objective

The aim of this study is to evaluate the predictive value of mitral L wave on AF recurrence after RFCA.

Methods

250 patients including 164 paroxysmal AF (65.6%) and 86 non-paroxysmal AF (34.4%) who received RFCA in single center from January 2015 to December 2016 were enrolled consecutively. Echocardiographic examinations before RFCA were recorded, and the mitral L wave was defined as a distinct mid-diastolic flow velocity with a peak velocity ≥20 cm/s following the E wave. Systematic follow-up was conducted after RFCA. Univariate and multivariate analyses were carried out to determine the factors predicting late recurrence of AF (LRAF) which means AF recurrence after 3 months. Enrolled patients were divided into groups with the L wave (L-group; n=57) or without the L wave (NL-group; n=193) based on the findings of echocardiographic examinations.

Results

During a follow-up of 35.0±17.6 months, the ratio of LRAF in the L-group was significantly higher than that in the NL-group (32 (56.1%) vs. 41 (21.2%), Hazard ratio [HR]: 3.55, 95% confidence interval [CI]: 2.33 - 5.42, p<0.001). Among the clinical factors, presence of mitral L wave, BNP value, non-paroxysmal AF and moderate-severe mitral regurgitation were related to LRAF. A multivariate analysis using a Cox proportional hazard model found that presence of mitral L wave (HR: 2.67, 95% CI: 1.30 - 5.48, p=0.007) was significantly associated with LRAF.

Conclusion

This study revealed that mitral L wave predicts late recurrence of AF after RFCA.

Funding Acknowledgement

Type of funding sources: None.

Identification of an allosteric and Smad3-selective inhibitor of p38αMAPK using a substrate-based approach

p38α mitogen activated protein kinase (MAPK) plays important roles in multiple cellular functions by phosphorylating a wide variety of substrates, and therefore, p38α MAPK has been considered as an important drug target. In this study, we designed peptide-based inhibitors for p38α MAPK, which can only inhibit the Smad3 phosphorylation specifically, by targeting the KIM binding site of p38α MAPK. Peptide 6 showed a significant inhibitory potency for the Smad3 phosphorylation by p38α MAPK. Peptide 6 showed no ATP dependency, and did not inhibit the phosphorylation of other substrates by p38α MAPK. The discovery of peptide 6 by targeting the KIM binding site likely provide an opportunity for the discovery of a novel class of allosteric and substrate-specific p38α MAPK inhibitors.

Structural basis for producing selective MAP2K7 inhibitors

Mitogen-activated protein kinase kinase 7 (MAP2K7) in the c-Jun N-terminal kinase signal cascade is an attractive drug target for a variety of diseases. The selectivity of MAP2K7 inhibitors against off-target kinases is a major barrier in drug development. We report a crystal structure of MAP2K7 complexed with a potent covalent inhibitor bearing an acrylamide moiety as an electrophile, which discloses a structural basis for producing selective and potent MAP2K7 inhibitors.

Electrocardiographic evaluation of depolarization and repolarization abnormalities in breast cancer patients with HER2-inhibitor related cardiac dysfunction

Background

The arrhythmic substrates of the myocardium such as depolarization and repolarization abnormalities are thought to reflect cardiac dysfunction prior to the morphologic left ventricular dysfunction. Activation time (AT), recovery time (RT) and T wave peek-end interval dispersion (Tpe-dispersion) are useful indicators of the arrhythmic substrate. We examined the appearance of depolarization and repolarization abnormalities in patients with cancer therapeutics-related cardiac dysfunction (CTRCD) using AT, RT and Tpe-dispersion.

Methods

We conducted a standardized case-control study of CTRCD with 40 patients who developed breast cancer and treated with trastuzumab (13 cases and 27 controls). We assessed the relation between electrocardiographic indexes, including AT, RT and corrected Tpe-dispersion, and CTRCD. QT intervals were measured by Fridericia method, and QT observer 3 software were used for the measurement of all electrocardiographic indexes.

Results

LVEF in case and control group were 45.7±8% and 69.2±6%, respectively. AT in aVR lead was significantly higher in case group compared with control (28.8±7ms vs 22.8±5ms, P=0.02). corrected Tpe-dispersion tended to be higher in case group than that of control group (43.2±19ms vs 31.9±10ms, P=0.06). QT dispersion and RT dispersion were not different between case and control group.

Conclusions

Our study demonstrated that AT in aVR may predict cardiac dysfunction in breast cancer patients with HER2-inhibitor related cardiac dysfunction. More detailed studies using other modalities which can detect depolarization and repolarization abnormalities, including ventricular late potentials and T wave alternans, are needed.

Funding Acknowledgement

Type of funding source: None

Bifidobacterium Breve A1 Supplementation Improved Cognitive Decline in Older Adults with Mild Cognitive Impairment: An Open-Label, Single-Arm Study

OBJECTIVES

We previously reported the therapeutic potential of Bifidobacterium breve A1 (B. breve A1) for preventing cognitive impairment in Alzheimer's disease model mice, which suggested that supplementation of the probiotics could be an effective therapeutic strategy for managing cognitive function in mild cognitive impairment (MCI).

DESIGN AND SETTINGS

We conducted an open-label, single-arm study to examine the effects of 24-week supplementation of B. breve A1 on elderly with MCI in Aki Orthopedics Rehabilitation Clinic in Japan.

PARTICIPANTS

27 participants were screened by their Mini Mental State Examination (MMSE) scores.

MEASUREMENTS

Cognitive function was assessed using MMSE and Digit Symbol Substitution Test (DSST) at baseline and every 8 weeks. Mental condition and quality of life for gastrointestinal symptoms were measured using the Profile of Mood States 2nd Edition (POMS2), and the Gastrointestinal Symptom Rating Scale (GSRS).

RESULTS

Of the 27 participants enrolled, 19 completed the study. MMSE scores were significantly increased during the intervention by mixed model Dunnett's test and Wilcoxon signed-rank tests (+1.7, P < 0.01). POMS2 and GSRS scores were significantly improved during intervention when analyzed by Wilcoxon signed-rank tests.

CONCLUSION

The present study showed that oral supplementation of B. breve A1 in participants with MCI improved cognitive function, thus suggesting the potential of B. breve A1 for improving cognitive function and maintaining quality of life of the elderly. Further randomized, double-blind placebo-controlled studies are worth conducting to examine the beneficial effect of B. breve A1.

Building a setup capable of characterizing large and low-loss optics: "STAR"

We have built a setup called STAR that is capable of characterizing large and very low-loss optics. STAR stands for scattering, transmittance, absorption, and reflectance of the setup's measurement items using 1064 nm laser light, a wavelength in which we are currently interested. Thanks to the design concept in which most of the optical components are shared by each measurement, the system is reasonably compact and can be quickly switched from one measurement setting to another with only minor modification and without offloading the piece to be measured from the setup. The instrument is capable of scanning large areas of 500 mm diameter or larger and can be used for both coated and uncoated optics. It is described here in detail, and the results of some measurements are presented.

Gastrectomy with or without omentectomy for cT3–4 gastric cancer: a multicentre cohort study

Background

Omentectomy is performed widely for locally advanced gastric cancer to prevent disease recurrence. However, its clinical benefit is unknown.

Methods

This retrospective cohort study compared the outcome of gastrectomy with preservation of the omentum (GPO) and gastrectomy with resection of the omentum (GRO) among patients with cT3–T4 gastric cancer who underwent gastrectomy between 2006 and 2012 in one of five participating institutions. A consensus conference identified 28 variables potentially associated with outcome after gastrectomy for the estimation of propensity scores, and propensity score matching (PSM) was undertaken to control for possible confounders. Postoperative surgical outcomes, overall survival and disease recurrence were compared between GPO and GRO.

Results

A total of 1758 patients were identified, of whom 526 remained after PSM, 263 in each group. Median follow-up was 4·9 (i.q.r. 3·1–5·9) years in the GRO group and 5·0 (2·5–6·8) years in the GPO group. The incidence of postoperative complications of Clavien–Dindo grade III or more was significantly higher in the GRO group (17·5 versus 10·3 per cent; P = 0·016). Five-year overall survival rates were 77·1 per cent in the GRO group and 79·4 per cent in the GPO group (P = 0·749). There were no significant differences in recurrence rate or pattern of recurrence between the groups.

Conclusion

Overall survival and disease recurrence were comparable in patients with cT3–4 gastric cancer who underwent GPO or GRO.

P93 The usefulness of dual cardiac autonomic nervous modulation assessment for prediction of mortality in patients with relatively preserved left ventricular ejection fraction

Background

Recent guidelines have stated that reduced left ventricular ejection fraction (LVEF) is the gold standard marker for identifying patients at risk for cardiac mortality. Although reduced LVEF identifies patients at an increased risk of cardiac arrest, sudden cardiac deaths (SCDs) occur considerably more often in patients with relatively preserved LVEF. Current guidelines on SCDs risk stratification do not adequately cover this general population pool. Heart rate variability (HRV) and heart rate turbulence (HRT) are non-invasive electrocardiography (ECG)-based techniques capable of providing relevant information on the cardiac autonomic nervous modulation. Although a large body of evidence about autonomic nervous modulation markers has been reported, the usefulness of HRV and HRT parameters for risk stratification in such patients with relatively preserved LVEF has not yet been elucidated.

Purpose

This study aimed to evaluate HRV and HRT parameters for predicting cardiac mortality in patients with structural heart disease (SHD), including ischemic heart disease, dilated cardiomyopathy and valvular heart disease, who have mid-range left ventricular dysfunction (LVD).

Methods

We prospectively enrolled 229 patients (187 men, age 63 ± 13 years) with SHD who have mid-range LVD (LVEF &gt; 40%). HRV and HRT parameters based on 24-hour ambulatory ECG recordings (Fukuda Denshi Co., Ltd., Tokyo, Japan) were evaluated as follows; SDNN, triangular index, high and low frequency HRV, turbulence onset and slope. The primary endpoint was all-cause mortality. Univariate and multivariate Cox regression analysis were used to assess the association between these cardiac autonomic nervous modulation and mortality.

Results

During a mean follow-up of 21 ± 11 months, all-cause mortality was seen in 11 (4.8%) patients. Univariate Cox regression analysis showed that reduced SDNN (&lt;50ms), reduced triangular index (&lt;20ms) and HRT category 2 were significantly associated with the primary endpoint (P &lt; 0.05). When HRT category 2 combined with reduced SDNN, Multivariate Cox regression analysis revealed that this combination more strongly associates with the primary endpoint (hazard ratio =7.91, 95%CI, 1.82-34.2; P = 0.006).

Conclusion

Dual cardiac autonomic nervous modulation assessment which combined HRT and HRV could be a superior technique to predict mortality in patients with relatively preserved LVEF.

Structural insights for producing CK2α1-specific inhibitors

Casein kinase 2 catalytic subunit (CK2α) is classified into two subtypes CK2α1 and CK2α2. CK2α1 is a drug discovery target, whereas CK2α2 is an off-target of CK2α1 inhibitors. High amino acid sequence homology between these subtypes hampers efforts to produce ATP competitive inhibitors that are highly selective to CK2α1. Hematein was identified previously as a non-ATP-competitive inhibitor for CK2α1, whereas this compound acts as an ATP competitive CK2α2 inhibitor. Crystal structures of CK2α1 and CK2α2 in complex with hematein revealed distinct binding features that provide structural insights for producing CK2α1-selective inhibitors.

Protein Allostery in Rational Drug Design

This chapter focuses on protein kinases that transfer the phosphate group of ATP to the hydroxyl group of a substrate protein. Five hundred eighteen human protein kinases are classified into serine/threonine kinases and tyrosine kinases and individually or synergistically transduce physiologic stimuli into cell to promote cell proliferation or apoptosis, etc. Protein kinases are identified as drug targets because dysfunction of kinases leads to severe diseases such as cancers and autoimmune diseases. A large number of the crystal structures of the protein kinase inhibitor complex are available in Protein Data Bank and facilitated the drug discovery targeting protein kinases. The protein kinase inhibitors are classified into categories, Type-I, Type-II, Type-III, Type-IV, and Type-V, and as a separate class, covalent-type inhibitors. In any type, a protein kinase inhibitor bound to the allosteric region is advantageous in terms of selectivity compared to the traditional ATP-competitive one. In the following sections, the successful and promising examples of the partially or fully allosteric protein kinase inhibitors are illustrated in the following pages.

Ensemble structural analyses depict the regulatory mechanism of non-phosphorylated human MAP2K4

Mitogen-activated protein kinase kinase 4 (MAP2K4) plays a critical role in regulating the stress-activated protein kinase signaling cascade. A small angle X-ray scattering experiment, a powerful technique for analyzing a solution structure cleared from the structural artifacts due to crystal packing, provided the ensemble structures of human non-phosphorylated MAP2K4 in three states involving the apo form, the binary complex with an ATP analogue, and the ternary complex with the ATP analogue and substrate peptide. These ensemble structures provided more detailed mechanisms for regulating MAP2K4 in addition to those delineated only by the crystal structures in three states.

P5639Risk stratification for mortality using electrocardiographic markers based on 24-hour holter recordings: the JANIES-SHD study

Background

Recent guidelines have stated that reduced left ventricular ejection fraction (LVEF) is the gold standard marker for identifying patients at risk for cardiac mortality. Although reduced LVEF identifies patients at an increased risk of cardiac arrest, sudden cardiac deaths (SCDs) occur considerably more often in patients with relatively preserved LVEF. Current guidelines on SCD risk stratification do not adequately cover this general population pool. Several noninvasive electrocardiographic (ECG) risk stratifiers that reflect depolarization abnormality, repolarization abnormality, and autonomic imbalance have been evaluated so far. With current therapeutic advances using new medicines or devices, an LVEF is often preserved in patients with structural heart disease (SHD). However, the usefulness of noninvasive ECG markers for risk stratification in such a patient population has not yet been elucidated.

Purpose

This study aimed to assess clinical indices and ECG markers based on 24-hour Holter ECG recordings for predicting cardiac mortality in patients with SHD who have left ventricular dysfunction (LVD) but relatively preserved LVEF.

Methods

In total, 1,829 patients were enrolled into the Japanese Multicenter Observational Prospective Study (JANIES study). In this study, we analyzed data of 719 patients (569 men, age 64±13 years) with SHD including mainly ischemic heart disease (65.8%). As ECG markers based on 24-hour Holter recordings, nonsustained ventricular tachycardia (NSVT), ventricular late potentials, and heart rate turbulence (HRT) were assessed. The primary endpoint was all-cause mortality, and the secondary endpoint was fatal arrhythmic events.

Results

During a mean follow-up of 21±11 months, all-cause mortality was eventually observed in 39 patients (5.4%). Among those patients, 32 patients (82%) suffered from cardiac causes such as heart failure and arrhythmia. Multivariate Cox regression analysis showed that after adjustment for age and LVEF, documented NSVT (hazard ratio=2.82, 95% confidence interval [CI]: 1.38–5.76, P=0.005) and abnormal HRT (hazard ratio=2.31, 95% CI: 1.15–4.65, P=0.02) were significantly associated with the primary endpoint. These two ECG markers also had significant predictive values with the secondary endpoint. The combined assessment documented NSVT and abnormal HRT improved predictive accuracy.

Conclusion

This study demonstrated that combined assessment of documented NSVT and abnormal HRT based on 24-hour Holter ECG recordings are recommended for predicting future serious events in SHD patients who have relatively preserved LVEF.

Acknowledgement/Funding

Grants-in-Aid (21590909, 24591074, and 15K09103 to T.I.) for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technol

P3754Comparison of the transdermal bisoprolol patch with the oral bisoprolol fumarate administration as a therapeutic agent for idiopathic frequent premature ventricular contractions

Background

The transdermal bisoprolol patch (TB) was designed to maintain a sustained concentration of bisoprolol in plasma by higher trough concentration than the oral bisoporolol fumarate administration (OB). It is unclear whether the TB is as effective in treating idiopathic premature ventricular contractions (PVCs) as the OB.

Purpose

We compared the efficacy between the TB and OB in treating idiopathic PVCs while considering their duration of action.

Methods

Among 198 patients with a PVC count of ≥3,000 beats/24 hours, 84 patients were divided into groups treated with TB 4mg (n=50) or OB 2.5mg (n=34). The PVCs were divided into positive heart rate (HR)-dependent PVCs (P-PVCs) and non-positive HR-dependent PVCs (NP-PVCs) based on the relationship between the hourly PVCs density and hourly mean HR. To evaluate the efficacy, PVC counts by 24-hour Holter electrocardiograms were measured at baseline and at 1 month after the initiation of the therapy.

Results

There were no significant between-group differences for the mean HR, PVC count, or type of PVCs. Both the TB (from 16,692±9,737 to 10,442±10,711 beats/24 hours, P<0.001) and OB (from 19,633±16,298 to 9,235±12,124 beats/24 hours, P<0.001) significantly decreased the total PVC count after the initiation of therapy, and a comparison between the two drugs showed no significant difference (P=0.46). In the P-PVC group, both the TB and OB significantly decreased the total PVC count (P<0.001, P=0.022 respectively), PVC count during the day-time (P<0.001, P=0.030 respectively), and PVC count during the night-time (P=0.0038, P=0.022 respectively). In contrast, in the NP-PVC group, neither the TB nor OB made any significantly change in the total PVC count (P=0.079, P=0.10 respectively), PVC count during the day-time (P=0.35, P=0.12 respectively), or PVC count during the night-time (P=0.11, P=0.12 respectively). The TB exhibited a significant reduction during each time period regarding the changes within 24-hours in the P-PVC count from baseline, while the OB did not significantly reduce the P-PVC count from baseline during each time period between 0 and 5 o'clock.

Conclusions

Compared with the OB, the TB could be used with the same efficacy for reducing the PVC count. The TB could be a more useful therapeutic agent for idiopathic P-PVCs during a 24-hour period than the OB.

P6559Long-term follow-up and outcomes of patients with discontinuation of oral anticoagulant therapy after successful ablation procedures for atrial fibrillation

Background

Oral anticoagulant therapy (OAT) is effective for preventing strokes in atrial fibrillation (AF) patients. Currently, there is controversy regarding the discontinuation of OATs in patients with ablation procedures to eliminate AF.

Aim

We investigated the incidence of major bleeding and ischemic strokes/systemic embolisms in low-risk patients that discontinued OATs after successful AF ablation procedures.

Methods

Of 330 consecutive patients that underwent AF ablation procedures and were prescribed one of the direct oral anticoagulants or warfarin, 207 AF patients (158 men, mean age 61±11 years) who discontinued OATs three months after the procedure were enrolled. The average CHADS2 and HAS-BLED scores were 1.0±0.9 and 1.2±1.0, respectively, which meant that most patients had a low risk for strokes.

Results

During follow-up, 31 patients (15%) had recurrences of AF. Those patients underwent a re-ablation procedure and then re-discontinued their OATs three months after the session. During a 60±13 months follow-up, major bleeding was observed in five patients (2.4%) and was associated with a higher HAS-BLED score (2.2±0.4 vs. 1.1±1.0, P=0.027). In contrast, none of the patients experienced ischemic strokes/systemic embolisms.

Conclusions

This prospective study demonstrated that in patients with successful ablation procedures and low risk scores for AF management, OATs could be discontinued three months after the procedure. Unnecessary continuation of OATs may increase the incidence of major bleeding during the follow-up.

Association between blood omega-3 polyunsaturated fatty acids and the gut microbiota among breast cancer survivors

Omega-3 polyunsaturated fatty acids (PUFAs) are essential nutrients demonstrated to have health benefits, such as decreasing the risk of coronary heart disease, improving parameters associated with metabolic syndrome, and decreasing anxiety symptoms and depression risk. Previous intervention studies indicated the association between blood or tissue PUFA levels and the gut microbiota; however, the details remain incompletely elucidated. We conducted a cross-sectional study to examine the association between PUFAs and the gut microbiota among breast cancer survivors. Adults who had been diagnosed with invasive breast cancer more than one year ago and were not currently undergoing chemotherapy were enrolled. Capillary blood and faecal samples were obtained to assess the blood PUFA levels and gut microbiota compositions. The mean age (n=124) was 58.7 years, and 46% of the participants had a history of chemotherapy. Multiple regression analysis controlling for possible confounders indicated that an increased relative abundance of Actinobacteria was significantly associated with increased levels of docosahexaenoic acid (DHA, beta=0.304, q<0.01). At the genus level, the abundance of Bifidobacterium was positively associated with the level of DHA (beta=0.307, q<0.01). No significant association between omega-6 PUFAs and the relative abundances of gut microbiota members was observed. In addition, analyses stratified by the history of chemotherapy indicated significant associations of PUFA levels with the abundance of some bacterial taxa, including the phylum Actinobacteria (DHA, beta=0.365, q<0.01) and Bacteroidetes (EPA, beta=-0.339, q<0.01) and the genus Bifidobacterium (DHA, beta=0.368, q<0.01) only among participants without a history of chemotherapy. These findings provide the first evidence of positive associations between the abundances of Bifidobacterium among the gut microbiota and the levels of omega-3 PUFAs in the blood. Further studies are required to gain additional insight into these associations in healthy subjects as well as into the causality of the relationship.

Asymmetric Phosphorus Incorporation in Homoepitaxial P-Doped (111) Diamond Revealed by Photoelectron Holography

Diamond has two crystallographically inequivalent sites in the unit cell. In doped diamond, dopant occupation in the two sites is expected to be equal. Nevertheless, preferential dopant occupation during growth under nonequilibrium conditions is of fundamental importance, for example, to enhance the properties of nitrogen-vacancy (N-V) centers; therefore, this is a promising candidate for a qubit. However, the lack of suitable experimental techniques has made it difficult to study the crystal- and chemical-site-resolved local structures of dopants. Here, we confirm the identity of two chemical sites with asymmetric dopant incorporation in the diamond structure, via the photoelectron holography (PEH) of heavily phosphorus (P)-doped diamond prepared by chemical vapor deposition. One is substitutionally incorporated P with preferential site occupations and the other can be attributed to a PV split vacancy complex with preferential orientation. The present study shows that PEH is a valuable technique to study the local structures around dopants with a resolution of crystallographically inequivalent but energetically equivalent sites/orientations. Such information provides strategies to improve the properties of dopant related-complexes in which alignment is crucial for sensing of magnetic field or quantum spin register using N-V centers in diamond.

A promiscuous kinase inhibitor delineates the conspicuous structural features of protein kinase CK2a1

Protein kinase CK2a1 is a serine/threonine kinase that plays a crucial role in the growth, proliferation and survival of cells and is a well known target for tumour and glomerulonephritis therapies. Here, the crystal structure of the kinase domain of CK2a1 complexed with 5-iodotubercidin (5IOD), an ATP-mimetic inhibitor, was determined at 1.78 Å resolution. The structure shows distinct structural features and, in combination with a comparison of the crystal structures of five off-target kinases complexed with 5IOD, provides valuable information for the development of highly selective inhibitors.

Two Cases of Equine Multinodular Pulmonary Fibrosis in Japan

Equine multinodular pulmonary fibrosis (EMPF) is a recently described form of interstitial pneumonia associated with equine herpesvirus type 5 (EHV-5). This disease has been reported in North and South America, Europe and Oceania but not, to our knowledge, in horses in Japan. We diagnosed EMPF in two Thoroughbred horses in Japan on the basis of gross and histopathological findings. In both cases, significant gross lesions, restricted to the lungs, consisted of numerous firm and coalescing nodules widely distributed throughout the lung. The nodules were <3 cm in diameter and pale white to tan in colour. Microscopically, they showed severe interstitial fibrosis and infiltration of macrophages, neutrophils, lymphocytes and a few eosinophils. The residual alveoli were lined by cuboidal epithelial cells (type II pneumocytes) and filled with many macrophages, which rarely displayed oval eosinophilic to amphophilic intranuclear inclusion bodies. Polymerase chain reaction and sequence analyses identified the glycoprotein H gene of EHV-5, and in-situ hybridization detected EHV-5 in the alveolar macrophages in the lesions. In one case, electron microscopy revealed herpesvirus-like particles and EHV-5 was isolated from pulmonary lesions.

Precision Analysis of the ^{136}Xe Two-Neutrino ββ Spectrum in KamLAND-Zen and Its Impact on the Quenching of Nuclear Matrix Elements

We present a precision analysis of the ^{136}Xe two-neutrino ββ electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ββ rate allows us to measure the ratio of the leading and subleading 2νββ nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ββ decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ββ NMEs.

Abstract OT2-01-05: A randomized controlled trial comparing post-operative intensive follow-up with standard follow-up in high-risk breast cancer patients (JCOG1204: INSPIRE)

Background: The standard follow-up after surgery for breast cancer includes periodic interviews, clinical examinations, and mammography, but many institutions are conducting intensive follow-up including periodic computed tomography(CT), magnetic resonance imaging(MRI), and bone scintigraphy in the world, despite the lack of evidence to support this approach. While intensive follow-up may contribute to prolonged survival through earlier diagnosis and treatment of relapse, it has the disadvantages of high effort and costs placed on patients(pts) and healthcare workers, radiation exposure for imaging examinations, and overtreatment owing to false-positive results. Although past two randomized trials could not show significant difference in overall survival (OS), as imaging methods have remarkably improved, leading to the earlier detection of relapse, and medical therapies have remarkably improved in recent years, randomized controlled trials are needed to confirm whether intensive follow-up can really prolong survival sufficiently to offset these disadvantages in high-risk breast cancer pts.

Trial design: This study is a multi-institutional two-arm open label randomized controlled phase III trial being conducted with the participation of 42 hospitals belonging to the Breast Cancer Study Group of Japan Clinical Oncology Group. Eligible pts are randomized either to the intensive follow-up group or to the standard follow-up group; the former will undergo physical examination, bone scintigraphy, chest and abdominal CT, brain MRI/CT and frequent tumor markers, whereas the latter will undergo physical examination at the same frequency and tumor markers will be evaluated once a year. Mammography once a year is planned for both groups. This trial has been registered at the UMIN Clinical Trials Registry as UMIN000012429.

Eligibility criteria: High-risk breast cancer pts, who are expected to have recurrence rates of over 30% within 5 years after surgery. The main inclusion criteria are as follows: four or more axillary nodal metastases in the estrogen receptor (ER) positive pts without neoadjuvant chemotherapy(NC)., axillary node metastases in ER-negative pts without NC, axillary nodal metastases in ER-positive pts with NC, histologically proven residual invasive cancer in the breast or axilla in ER-negative with NC.

Specific Aims: The primary endpoint is OS, and secondary endpoints are disease-free survival, relapse-free survival, distant metastasis–free survival, OS in intrinsic subtypes, actual number of implemented examinations, compliance with pre-specified examinations, and adverse events.

Statistical methods: The primary endpoint will require a total of 538 events to be assessed in order to obtain a statistical power of 80% with a one-sided significance level of 0.05. Thus, the planned sample size to compare the two survival curves is set at 1500 pts, assuming an accrual time of 6 years and a follow-up time of 7 years according to the Schoenfeld and Richter's method.

Present accrual and target accrual: The trial was activated in November 2013. 773 pts have been enrolled by the end of June 2018.

Contact: Principal investigator Takashi Hojo MD tahojo@east.ncc.go.jp

Citation Format: Hojo T, Masuda N, Shibata T, Mizutani T, Shien T, Kinoshita T, Iwatani T, Kanbayashi C, Kitagawa D, Tsuneizumi M, Iwata H. A randomized controlled trial comparing post-operative intensive follow-up with standard follow-up in high-risk breast cancer patients (JCOG1204: INSPIRE) [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 OT2-01-05.

Cell-based screen identifies a new potent and highly selective CK2 inhibitor for modulation of circadian rhythms and cancer cell growth

Compounds targeting the circadian clock have been identified as potential treatments for clock-related diseases, including cancer. Our cell-based phenotypic screen revealed uncharacterized clock-modulating compounds. Through affinity-based target deconvolution, we identified GO289, which strongly lengthened circadian period, as a potent and selective inhibitor of CK2. Phosphoproteomics identified multiple phosphorylation sites inhibited by GO289 on clock proteins, including PER2 S693. Furthermore, GO289 exhibited cell type-dependent inhibition of cancer cell growth that correlated with cellular clock function. The x-ray crystal structure of the CK2α-GO289 complex revealed critical interactions between GO289 and CK2-specific residues and no direct interaction of GO289 with the hinge region that is highly conserved among kinases. The discovery of GO289 provides a direct link between the circadian clock and cancer regulation and reveals unique design principles underlying kinase selectivity.