Evaluation of anorectal function using real-time tissue elastography before and after preoperative chemoradiotherapy

PURPOSE

This study aimed to clarify the relationship between changes in elasticity and anorectal function before and after chemoradiotherapy.

METHODS

This is a single-center prospective cohort study (Department of Surgical Oncology, The University of Tokyo). We established a technique to quantify internal anal sphincter hardness as elasticity using transanal ultrasonography with real-time tissue elastography. Twenty-seven patients with post-chemoradiotherapy rectal cancer during 2019-2022 were included. Real-time tissue elastography with transanal ultrasonography was performed before and after chemoradiotherapy to measure internal anal sphincter hardness as "elasticity" (hardest (0) to softest (255); decreased elasticity indicated sclerotic changes). The relationship between the increase or decrease in elasticity pre- and post-chemoradiotherapy and the maximum resting pressure, maximum squeeze pressure, and Wexner score were the outcome measures.

RESULTS

A decrease in elasticity was observed in 16/27 (59.3%) patients after chemoradiotherapy. Patients with and without elasticity decrease after chemoradiotherapy comprised the internal anal sphincter sclerosis and non-sclerosis groups, respectively. The maximum resting pressure post-chemoradiotherapy was significantly high in the internal anal sphincter sclerosis group (63.0 mmHg vs. 47.0 mmHg), and a majority had a worsening Wexner score (60.0% vs. 18.2%) compared with that of the non-sclerosis group. Decreasing elasticity (internal anal sphincter sclerosis) correlated with a higher maximum resting pressure (r = 0.36); no correlation was observed between the degree of elasticity change and maximum squeeze pressure.

CONCLUSION

Internal anal sphincter sclerosis due to chemoradiotherapy may correlate to anorectal dysfunction.

The Cavin-1/Caveolin-1 interaction attenuates BMP/Smad signaling in pulmonary hypertension by interfering with BMPR2/Caveolin-1 binding

Caveolin-1 (CAV1) and Cavin-1 are components of caveolae, both of which interact with and influence the composition and stabilization of caveolae. CAV1 is associated with pulmonary arterial hypertension (PAH). Bone morphogenetic protein (BMP) type 2 receptor (BMPR2) is localized in caveolae associated with CAV1 and is commonly mutated in PAH. Here, we show that BMP/Smad signaling is suppressed in pulmonary microvascular endothelial cells of CAV1 knockout mice. Moreover, hypoxia enhances the CAV1/Cavin-1 interaction but attenuates the CAV1/BMPR2 interaction and BMPR2 membrane localization in pulmonary artery endothelial cells (PAECs). Both Cavin-1 and BMPR2 are associated with the CAV1 scaffolding domain. Cavin-1 decreases BMPR2 membrane localization by inhibiting the interaction of BMPR2 with CAV1 and reduces Smad signal transduction in PAECs. Furthermore, Cavin-1 knockdown is resistant to CAV1-induced pulmonary hypertension in vivo. We demonstrate that the Cavin-1/Caveolin-1 interaction attenuates BMP/Smad signaling and is a promising target for the treatment of PAH.

Development of an Iron(II) Complex Exhibiting Thermal- and Photoinduced Double Proton-Transfer-Coupled Spin Transition in a Short Hydrogen Bond

Multiple proton transfer (PT) controllable by external stimuli plays a crucial role in fundamental chemistry, biological activity, and material science. However, in crystalline systems, controlling multiple PT, which results in a distinct protonation state, remains challenging. In this study, we developed a novel tridentate ligand and iron(II) complex with a short hydrogen bond (HB) that exhibits a PT-coupled spin transition (PCST). Single-crystal X-ray and neutron diffraction measurements revealed that the positions of the two protons in the complex can be controlled by temperature and photoirradiation based on the thermal- and photoinduced PCST. The obtained results suggest that designing molecules that form short HBs is a promising approach for developing multiple PT systems in crystals.

Photochromic dinuclear iridium(III) complexes having phenoxyl-imidazolyl radical complex derivatives

We demonstrate that the phenoxyl-imidazolyl radical complex (PIC), which is a rate-tunable fast photoswitch, can be used as a ligand that directly coordinates with iridium (III) ions. The iridium complexes show the characteristic photochromic reactions originating from the PIC moiety, whereas the behaviour of transient species is substantially different from that of the PIC.

Molecular Structures and Vibrational Spectra of trans- and cis-Polyacetylene and Their Oligoenes Revisited Using Density Functional Theory Calculations

Polyacetylene, the most representative synthetic conducting polymer, has attracted much attention because it exhibits high conductivity upon doping. In this paper, molecular structures, electronic excitation energies, and Raman and infrared spectra were calculated using density functional theory for trans- and cis-oligoenes with various chain lengths up to the number of C═C bonds (n) of 100 and trans- and cis-polyacetylenes under one-dimensional periodic boundary condition. The harmonic vibrational frequencies obtained at the B3LYP/6-311G(d,p) level were scaled by the scaling factors determined with respect to the anharmonic vibrational frequencies using the B2PLYP method, in which the coefficients of the functional were optimized for trans-oligoenes. The calculated infrared and Raman frequencies reproduce reasonably well the observed frequencies for trans- and cis-polyacetylene. Based on the chain-length dependence of the calculated Raman spectra of trans-oligoenes, we proposed the possibility of longer conjugated trans-segments observed in the resonance Raman spectra of trans-polyacetylene excited at longer wavelengths of 647.1 and 1064 nm. We also elucidated the origin of the excitation-wavelength dependence of the resonance Raman spectra of trans-polyacetylene and the structure of isomerization intermediates from cis-form to trans-form. In addition, the previous assignments of Raman and infrared spectra of trans- and cis-polyacetylene were reexamined in the present study based on the chain-length dependence of the spectra.

Energy conversion and storage via photoinduced polarization change in non-ferroelectric molecular [CoGa] crystals

To alleviate the energy and environmental crisis, in the last decades, energy harvesting by utilizing optical control has emerged as a promising solution. Here we report a polar crystal that exhibits photoenergy conversion and energy storage upon light irradiation. The polar crystal consists of dinuclear [CoGa] molecules, which are oriented in a uniform direction inside the crystal lattice. Irradiation with green light induces a directional intramolecular electron transfer from the ligand to a low-spin Co^III centre, and the resultant light-induced high-spin Co^II excited state is trapped at low temperature, realizing energy storage. Additionally, electric current release is observed during relaxation from the trapped light-induced metastable state to the ground state, because the intramolecular electron transfer in the relaxation process is accompanied with macroscopic polarization switching at the single-crystal level. It demonstrates that energy storage and conversion to electrical energy is realized in the [CoGa] crystals, which is different from typical polar pyroelectric compounds that exhibit the conversion of thermal energy into electricity.

Coxsackievirus A11 is an immunostimulatory oncolytic virus that induces complete tumor regression in a human non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality worldwide. Innovative treatment is required to improve overall survival rates for advanced NSCLC. Oncolytic virotherapy using enteroviruses has emerged as a promising anticancer strategy. To identify a novel, potent virotherapy with an improved safety profile, we assessed the oncolytic activity of 28 enteroviral strains and focused on coxsackievirus A11 (CVA11). CVA11 infection caused extensive oncolytic activity in all three of the examined human NSCLC cell lines, with high intercellular adhesion molecule-1 (ICAM-1) expression associated with greater CVA11-induced cytotoxicity. In vitro inhibition analysis using a pan-caspase inhibitor and western blot detection of cleaved poly (ADP-ribose) polymerase (PARP) indicated that apoptosis partly contributed to CVA11-driven cytotoxicity. CVA11 infection-induced immunogenic cell death in vitro was strongly suggested by substantial calreticulin expression and release of high mobility group box-1 protein (HMGB1). Moreover, in vivo treatment of human NSCLC xenografts with intratumoral CVA11 injection caused complete tumor regression in all treated mice, without significant weight loss. Our findings indicate that novel oncolytic virotherapy utilizing CVA11 may be less toxic and more effective than current treatments for human NSCLC, thus warranting further investigation in clinical trial settings, especially in combination with immunotherapy.

Temporal changes in functional outcomes of stapled and hand-sewn ileal pouch-anal anastomosis for ulcerative colitis and familial adenomatous polyposis

AIM

Little is known about how ileal pouch-anal anastomosis (IPAA) influences anorectal manometric data. This study aimed to clarify temporal changes in anorectal manometric data and faecal incontinence in IPAA.

METHODS

We examined 32 patients with ulcerative colitis (UC) or familial adenomatous polyposis (FAP) undergoing restorative proctocolectomy with stapled or hand-sewn IPAA. Maximum resting pressure (MRP) and maximum squeezing pressure (MSP) were analysed before and 1-3, 6-9, and 12-24 months after IPAA. Cleveland Clinic Florida-Faecal Incontinence Score (CCF-FIS) was measured 6-9 and 12-24 months after IPAA.

RESULTS

Fourteen patients underwent stapled IPAA and 18 patients underwent hand-sewn IPAA. MRP decreased 1-3 months after stapled IPAA (median: 42.3 mmHg vs. 60.0 mmHg at preoperative value, p = 0.039), but recovered afterwards. In hand-sewn IPAA, the median MRP decreased to 29.5 mmHg at 1-3 months after IPAA (baseline: 64.8 mmHg, p < 0.0001), and remained unchanged thereafter. Stapled IPAA did not affect MSP; however, hand-sewn IPAA caused a reduction in the median MSP from 191.3 mmHg to 141.3 mmHg at 1-3 months (p = 0.035), which gradually increased afterwards. The median CCFFIS was 5.5 points at 6-9 months and 2 points at 12-24 months after stapled IPAA. The score was high (11 points) at 6-9 months but decreased to 5 points at 12-24 months after hand-sewn IPAA (p = 0.022).

CONCLUSION

We present time trends in functional outcomes of IPAA. MRP showed a transient decrease after stapled IPAA, whereas it remained low after hand-sewn IPAA. CCFFIS was high only at 6-9 months after hand-sewn IPAA.

Polygenic risk score associates with atherosclerosis severity at autopsy

Background

Polygenic risk scores (PRS) for coronary artery disease (CAD) are emerging as a potential method to improve cardiovascular risk prediction. Questions remain about their applicability to diverse populations as well as their correlation with coronary histopathology.

Purpose

To assess whether high genetic risk associates with histopathologic coronary plaque morphology.

Methods

We assessed 122 known CAD risk loci in 954 Black and White subjects within our sudden death registry to generate a PRS. The cohort was divided into quintiles according to z-score-standardized PRS, both in a race-stratified fashion and in the pooled sample. Detailed histopathologic examination of the coronary arteries was performed in all subjects.

Results

Subjects in the highest PRS quintile exhibited more severe atherosclerosis compared to subjects in the lowest quintile, with greater mean cross-sectional luminal narrowing (71.5% (95% CI, 66.6%-76.5%) vs. 56.6% (95% CI, 51.1%-62.1%); adjusted p&lt;0.001; Figure 1) and a higher frequency of calcification (adjusted OR 2.19; 95% CI 1.31–3.68; p=0.003) after adjustment for the first 10 principal components, age, sex, and race. Higher z-score-standardized PRS was predictive for the finding of severe atherosclerosis (i.e., ≥75% cross-sectional luminal narrowing) even after additional controlling for traditional CAD risk factors including hypertension, smoking, diabetes mellitus, and hyperlipidemia (adjusted OR 1.39; 95% CI 1.19–1.63; p&lt;0.001; Figure 2). Among Black subjects, higher PRS was associated with higher odds of plaque rupture (adjusted OR 1.31; 95% CI 1.03–1.66; p=0.03) and predicted CAD-associated cause of death among subjects younger than 50 years old (adjusted OR 1.26; 95% CI 1.01–1.58; p=0.04).

Conclusions

This is the first autopsy study investigating associations between PRS and atherosclerotic plaque morphology at a histopathologic level. Our pathological analysis suggests PRS correlates with plaque burden and coronary artery calcification and may be useful as a method for CAD risk stratification, especially in younger subjects.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): R01 HL141425 Leducq Foundation Grant

Controlling Diradical Character of Photogenerated Colored Isomers of Phenoxyl-Imidazolyl Radical Complexes

We propose a rational method for evaluating the diradical character of the photochromic phenoxyl-imidazolyl radical complex (PIC) derivatives based on their radical-radical coupling reaction rates. PIC consists of an imidazole ring, a phenoxyl ring, and a bridging unit that structurally connects them. The C-N bond formed between the imidazole and phenoxyl rings can be dissociated photochemically in a homolytic manner. The photochromism of PIC differs significantly from other photochromic molecules in that the transient colored open-ring isomer has a diradical character. The colored open-ring isomer returns promptly to the initial colorless closed-ring isomer by the intramolecular radical recombination reaction. By changing the aromaticity and substitution position of the bridging unit, it is possible to control the degree of contribution of the open-shell diradical and closed-shell quinoidal structures to the open-ring isomer. Systematic investigation of the photochromic reactions of several PIC derivatives revealed that the half-life of the open-ring isomers reflects the diradical character. Thus, the radical recombination reaction rate of the open-ring isomer of the PIC derivatives is an excellent parameter of the diradical character.

Impact of Door-to-Balloon Time Reduction Depending on the Killip Classification in Patients with ST-Segment Elevation Myocardial Infarction Transported by Emergency Medical Services

The coronavirus disease 2019 pandemic occurred in several countries, making the conventional medical system difficult to maintain. Recent recommendations aim to prevent nosocomial infections and infections among health care workers. Therefore, establishing a cardiovascular medical system under an emergency for patients with ST-segment elevation myocardial infarction (STEMI) is desired. This study aimed to determine the relationship between prognosis and door-to-balloon time (DBT) shortening based on the severity on arrival.This retrospective, multi-center, observational study included 1,127 consecutive patients with STEMI. These patients were transported by emergency medical services and underwent primary percutaneous coronary intervention. Patients were stratified according to the Killip classification: Killip 1 (n = 738) and Killip ≥ 2 (n = 389) groups.Patients in the Killip ≥ 2 group were older, with more females, and more severity on arrival than those in the Killip 1 group. The 30-day mortality rate in the Killip 1 and Killip ≥ 2 groups was 2.2% and 18.0%, respectively. The Killip ≥ 2 group had a significant difference in the 30-day mortality between patients with DBT ≤ 90 minutes and those with DBT > 90 minutes; however, this did not occur in the Killip 1 group. Furthermore, multivariate analysis revealed that DBT ≤ 90 minutes was not a significant predictive factor in the Killip 1 group; however, it was an independent predictive factor in the Killip ≥ 2 group.DBT shortening affected the 30-day mortality in STEMI patients with Killip ≥ 2, although not those with Killip 1.

Excited-state dynamics of dipyrrolyldiketone difluoroboron complexes

Anion-responsive photofunctional materials have been extensively studied because anions are important for biotic activity and constitute the building blocks of elegant supramolecular architectures. A number of fluorescent anion receptors that can probe anions in their environments have been reported, but the excited states of many of these molecules remain elusive. Studies on excited-state dynamics provide fruitful information for optimizing the emission properties, minimizing the photodegradation and photorelease of anions, and exploring novel photofunctions. In this study, we investigated the excited-state dynamics of an aryl-substituted dipyrrolyldiketone difluoroboron complex, a π-conjugated anion receptor, by time-resolved visible and infrared absorption spectroscopy and emission decay measurements combined with quantum chemical calculations. Anion binding was found to alter the radiative and nonradiative rate constants and the excited-state absorption of the anion receptor. In contrast, the molecular structures and binding abilities were similar in the S₀ and S₁ states.

Requirement of Cavin-2 for the expression and stability of IRβ in adequate adipocyte differentiation

Objective

Adipogenesis plays an essential role in maintaining energy and hormonal balance. Cavin-2, one of the caveolae-related proteins, is abundant in adipocytes, the leading site of adipogenesis. However, the details of the roles of Cavin-2 in adipogenesis remain unknown. Here, we demonstrate the requirement of Cavin-2 for the expression and stability of IRβ in adequate adipocyte differentiation.

Methods

Cavin-2 knockout (Cavin-2 KO) and wild-type (WT) mice were fed with a high-fat diet (HFD) for 8 weeks. We evaluated body weight, food intake, and several tissues. Glucose homeostasis was assessed by glucose and insulin tolerance tests. Insulin signaling in epididymal white adipose tissue (eWAT) was determined by Akt phosphorylation. In vitro study, we evaluated adipocyte differentiation, adipogenesis-related genes, and insulin signaling to clarify the relationship between Cavin-2 and adipogenesis under the manipulation of Cavin-2 expression.

Results

Caveolae structure decreased in eWAT of Cavin-2 KO mice and Cavin-2 knockdown 3T3-L1 cells. Cavin-2 enhanced the stability of insulin receptor (IR) through direct association at the plasma membrane in adipocytes, resulting in accelerated insulin/IR/Akt signaling-induced adipogenic gene expression in insulin-containing solution-stimulated 3T3-L1 adipocytes. IR-mediated Akt activation also enhanced Cavin-2 and IR expression. Cavin-2 knockout mice showed insulin resistance with dyslipidemia and pathological hypertrophic adipocytes after a HFD.

Conclusions

Cavin-2 enhances IR stability through binding IR and regulates insulin signaling, promoting adequate adipocyte differentiation. Our findings highlight the pivotal role of Cavin-2 in adipogenesis and lipid metabolism, which may help to develop novel therapies for pathological obesity and adipogenic disorders.

•

Cavin-2 expression is increased progressively during adipocyte differentiation.

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Cavin-2 knockout shows little caveolae in 3T3L-1 adipocytes and eWAT of mice.

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Cavin-2 positively regulates adipogenesis through IR stabilization.

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Cavin-2 knockout mice with a high-fat diet show insulin resistance and dyslipidemia.

Energy-sparing by 2-methyl-2-thiazoline protects heart from ischaemia/reperfusion injury

AIMS

Cardiac ischaemia/reperfusion (I/R) injury remains a critical issue in the therapeutic management of ischaemic heart failure. Although mild hypothermia has a protective effect on cardiac I/R injury, more rapid and safe methods that can obtain similar results to hypothermia therapy are required. 2-Methyl-2-thiazoline (2MT), an innate fear inducer, causes mild hypothermia resulting in resistance to critical hypoxia in cutaneous or cerebral I/R injury. The aim of this study is to demonstrate the protective effect of systemically administered 2MT on cardiac I/R injury and to elucidate the mechanism underlying this effect.

METHODS AND RESULTS

A single subcutaneous injection of 2MT (50 mg/kg) was given prior to reperfusion of the I/R injured 10 week-old male mouse heart and its efficacy was evaluated 24 h after the ligation of the left anterior descending coronary artery. 2MT preserved left ventricular systolic function following I/R injury (ejection fraction, %: control 37.9 ± 6.7, 2MT 54.1 ± 6.4, P < 0.01). 2MT also decreased infarct size (infarct size/ischaemic area at risk, %: control 48.3 ± 12.1, 2MT 25.6 ± 4.2, P < 0.05) and serum cardiac troponin levels (ng/mL: control 8.9 ± 1.1, 2MT 1.9 ± 0.1, P < 0.01) after I/R. Moreover, 2MT reduced the oxidative stress-exposed area within the heart (%: control 25.3 ± 4.7, 2MT 10.8 ± 1.4, P < 0.01). These results were supported by microarray analysis of the mouse hearts. 2MT induced a transient, mild decrease in core body temperature (°C: -2.4 ± 1.4), which gradually recovered over several hours. Metabolome analysis of the mouse hearts suggested that 2MT minimized energy metabolism towards suppressing oxidative stress. Furthermore, 18F-fluorodeoxyglucose-positron emission tomography/computed tomography imaging revealed that 2MT reduced the activity of brown adipose tissue (standardized uptake value: control 24.3 ± 6.4, 2MT 18.4 ± 5.8, P < 0.05). 2MT also inhibited mitochondrial respiration and glycolysis in rat cardiomyoblasts.

CONCLUSIONS

We identified the cardioprotective effect of systemically administered 2MT on cardiac I/R injury by sparing energy metabolism with reversible hypothermia. Our results highlight the potential of drug-induced hypothermia therapy as an adjunct to coronary intervention in severe ischaemic heart disease.

Cavin-1 modulates BMP/Smad signaling through the interaction of Caveolin-1 with BMPRII in pulmonary artery endothelial cells

Background

Pulmonary hypertension (PH) is a progressive disease associated with poor outcomes. Caveolin-1 (Cav1) and Cavin-1 are components of caveolae, and Cav1 is identified as a related gene of pulmonary arterial hypertension (PAH). Gene mutations of bone morphogenetic protein type II receptor (BMPRII) is the most common cause of PAH. BMPRII is localized in caveolae and associates with Cav1. However, the role of the Caveolin-Cavin system on the BMP/Smad signaling and the PAH progression has not been well-known.

Purpose

Our study aims to investigate the relationship between Caveolin-Cavin system and BMP/Smad signaling pathway in pulmonary artery endothelial cells (PAECs). [Methods] Cav1 knockout mice were used to assess PH, and caveolae in PAECs were observed by electron microscope. After knocking down Cav1 and/or Cavin-1 in human PAECs (hPAECs) using siRNA, we evaluated the phosphorylation of Smad by Western blotting. Apoptosis was explored by flow cytometry. To assess the interaction between Cav1 and BMPRII, and the effect of Cavin-1 for this interaction and BMP/Smad signaling, we performed immunoprecipitation, Co-immunostaining, Proximal Ligation Assay (PLA), GST pulldown assay, and Western blotting.

Results

As in previous reports, Cav1 knockout mice exhibited PH with pulmonary vascular remodeling and right ventricular hypertrophy and PAECs isolated from Cav1 knockout mice showed caveolae disappearance. Cav1 knockdown in hPAECs reduced BMPRII at the plasma membrane and Smad 1/5/9 phosphorylation. Cav1 knockdown also significantly increased hypoxia-induced apoptosis in hPAECs. Co-immunostaining revealed that Cav1 was associated with BMPRII at the membrane of hPAECs. Cavin-1 inhibited the interaction of BMPRII with Cav1 and reduced BMPRII localization on the membrane of hPAECs. GST pulldown assay revealed that Cavin-1 and BMPRII were associated with Cav1 through the scaffolding domain in Cav1. These findings suggest that Cavin-1 and BMPRII are competitively associated with Cav1. Cavin-1 knockdown improved the interaction between Cav1 and BMPRII and inhibited both BMPRII reduction at the plasma membrane and Smad 1/5/9 dephosphorylation.

Conclusions

Cavin-1 affects the interaction of Cav1 with BMPRII at the plasma membrane and modulates BMP/Smad signaling in PAECs. The binding of Cavin-1 to Cav1 enhances the interaction between BMPR2 and Cav1, resulting in stabilization of BMPRII localization at the plasma membrane in PAECs and prevention of BMP/Smad signaling attenuation, which is important for PAH development.

Funding Acknowledgement

Type of funding sources: None.

Safe and Responsible Internet Use in a Connected World: Promoting Cyber-Wellness

Cyber-wellness concerns positive wellbeing in online spaces, including awareness of how to behave appropriately and protect oneself. We explain and illustrate the complex nature of cyber-wellness, focusing on four key aspects. Firstly, developing students’ information and media literacy skills is essential for promoting cyber-wellbeing. Such skills are also required for supporting democratic participation. Secondly, we identify and discuss the threats and challenges to young people’s cyber-wellbeing, arguing for the need to develop digital resilience. Thirdly, we discuss the role of policy at macro, meso and micro levels and how policy and educational practitioners can promote cyber-wellness awareness, knowledge and strategies. Finally we review the limited scholarship on cyber-wellness education and highlight the need to address this gap in the future. We conclude the article with consideration of the issues faced and opportunities for overcoming these. It is imperative that further work is undertaken on the conceptualisation of cyber-wellness and that concensus is developed. There are issues relating to the continual rapid developments of techologies and their uses; it is important to develop a shared understanding of the mutual relationship between technology and humans. Finally, there is a lack of guidance and good practice exemplars for cyber-wellness education.

Rectal neuroendocrine tumor with extracapsular lymph node metastasis: a case report

The presence of extramural tumor deposits without lymph node structure (EX) is an important prognostic factor in patients with colorectal carcinoma. However, there is no English literature on neuroendocrine tumor (NET) with EX. We report a patient with rectal NET with extracapsular metastasis of a regional lymph node that was considered to be EX. A 51-year-old Japanese woman with diabetes was referred to our hospital for further examination of a submucosal tumor in the lower rectum. She was diagnosed as having rectal NET by immunohistochemical analysis of a biopsy, and underwent laparoscopic low anterior resection with lymph node dissection and covering ileostomy. Pathological findings of the resected specimen showed that the primary tumor was NET-G1 without any lymphatic or venous invasion. A single metastatic deposit was found near the capsule of a NET-negative regional lymph node. She has been free from recurrence for nine months without adjuvant treatments. Extracapsular metastasis of NET on a dissected lymph node in our case was considered to correspond to EX as defined for colorectal carcinoma. This rare case suggests that NET can disseminate to form EX in a similar manner to colorectal carcinoma.

Pachinko/Pachislot Playing Participation in Japan: Results from a National Survey

To understand individuals' pachinko/pachislot playing behavior, one of the major games in Japan, we conducted a national study of Japanese residents between 18 and 79 years old. From resident records, in which all Japanese citizens are registered, 9,000 individuals were chosen by the two-stage stratified random sampling method. The number of individuals who submitted valid responses was 5,060 (response rate: 56.2%). The analysis result indicated that 582 (11.5%) played pachinko/pachislot in the last 12 months ("past-year players"). Compared to "non-players" (those who never played pachinko/pachislot before or did not play in the last 12 months), past-year players had higher 12-month participation rates in all 10 gambling activities other than pachinko/pachislot. To compare demographic variables between the past-year players and non-players, χ2 tests were carried out. The tests discovered that past-year players were more likely to be males in their 30s, junior high school graduates, and making a similar annual household income to the median value for all respondents. Next, demographic variables were compared for each participation level and significant differences between age groups were found; participants in their 60s and 70s visited pachinko/pachislot parlors more frequently than those in their 20s to 40s. This is the first study to reveal the details of pachinko/pachislot playing behavior in Japan.RésuméUne enquête nationale a été menée auprès de résidents japonais âgés de 18 à 79 ans dans le but d’étudier le comportement des joueurs de pachinko/pachislot, l’un des principaux jeux pratiqués au Japon. À partir du registre de déclaration de résidence, auquel tous les citoyens du pays sont inscrits, 9000 personnes ont été sélectionnées en suivant la méthode d’échantillonnage aléatoire stratifié en deux étapes. Sur ce nombre, 5060 ont donné des réponses valides (taux de réponse : 56,2 %). Selon les résultats, 582 (11,5 %) ont joué au pachinko/pachislot dans les 12 derniers mois (« joueurs de l’année précédente »). Comparativement aux « non-joueurs » (à savoir ceux qui n’ont jamais pratiqué ce jeu dans le passé ou au cours des 12 derniers mois), les joueurs de l’année précédente affichent sur 12 mois des taux de participation plus élevés à 10 autres activités de jeux de hasard outre le pachinko/pachislot. Des tests de chi-square ont été réalisés en vue de comparer les variables démographiques entre les joueurs de l’année précédente et les non-joueurs. Les premiers étaient plus susceptibles d’être des hommes dans la trentaine et des diplômés des écoles intermédiaires, dont le revenu familial annuel se rapprochait de la valeur médiane pour l’ensemble des répondants. Les variables démographiques ont été comparées pour chaque niveau de participation, faisant apparaître des différences notables entre les groupes d’âge : les sexagénaires et les septuagénaires fréquentaient les maisons de pachinko/pachislot plus souvent que les générations de la vingtaine à la quarantaine. Cette étude est la toute première à révéler des détails sur les habitudes de jeux de pachinko/pachislot au Japon.

Cavin-1 regulates BMP/Smad signaling through the interaction of Caveolin-1 with BMPRII in pulmonary artery endothelial cells

Background

Pulmonary hypertension (PH) is a progressive disease associated with poor outcome. Caveolin-1 (Cav1) is a component of caveolae and classified as a related gene of pulmonary arterial hypertension (PAH). Gene mutations of bone morphogenetic protein type II receptor (BMPRII) is a most common cause of PAH. BMPRII is localized in caveolae and associates with Cav1. However, the role of the Caveolin-Cavin system on the BMP/Smad signaling and the PAH progression has not been well-known.

Purpose

The aim of our study is to investigate the relationship between Caveolin-Cavin system and BMP/Smad signaling pathway and explore the mechanism of downstream signal transduction of BMP signaling by the interaction between Caveolin and BMPRII.

Methods

Cav1 knockout mice were used to assess PH and caveolae in pulmonary artery endothelial cells were observed by electron microscope. Cav1 and Cavin-1, which is a component of caveolae and form a complex with Cav1, were knocked-down in human pulmonary artery endothelial cell (hPAEC) using siRNA and phosphorylation of Smad signal was evaluated. Apoptosis of these cells was explored by flow cytometry. We investigated the interaction between Cav1 and BMPRII, and evaluated whether Cavin-1 affects this interaction and signal transduction of BMP signaling.

Results

As previously described, deletion of Cav1 revealed disappearance of caveolae in pulmonary artery endothelial cells (PAECs), and Cav1 knockout mice exhibited PH with pulmonary vascular remodeling and right ventricular hypertrophy. We then examined roles of Cav1 in human PAECs (hPAECs). Cav1 knockdown in hPAECs reduced phosphorylation of Smad 1/5/9. In addition, Cav1 knockdown significantly increased hypoxia-induced apoptosis in hPAEC. Knockdown of Cavin-1 reversed phosphorylation of Smad 1/5/9 decreased by Cav1 knockdown in BMP9 stimulation. Cavin-1 reversed the expression of BMPRII decreased by overexpression of Cav1. Cav1 was associated with Cavin-1 at the plasma membrane in PAECs. Cav1 also associated with BMPRII at the membrane of hPAECs that was inhibited by Cavin-1, and Cavin-1 reduced the localization of BMPRII to the membrane of hPAECs. These results suggest that BMPRII interacts with Cav1 via Cavin-1-associated localization at the plasma membrane in hPAECs, resulting in regulating BMP/Smad signaling pathway and involving in the development of PAH.

Conclusions

Cavin-1 affects the interaction of Cav1 with BMPRII at the membrane of PAECs, and regulates BMP/Smad signaling. These results reveal a previously undescribed function of Cavin-Caveolin system in the development of PAH through regulation of BMP/Smad signaling.

Funding Acknowledgement

Type of funding source: None

SDPR/Cavin-2 loss inhibits monocyte adhesion to endothelial cells in abdominal aortic aneurysm via suppressing the expression of adhesion molecules

Background

Abdominal aortic aneurysm (AAA) is a common and life-threatening vascular disease. The initial phase of AAA progression is vascular inflammation. Inflammation sites present adhesion molecules, such as vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1). These molecules play a crucial role in recruiting inflammatory cells to endothelial cells through NF-κB signaling. Endothelial cells express serum deprivation response (SDPR)/Cavin-2 localized in caveolae on the cell membrane. Although Cavin-2 is involved in such as cell proliferation, migration, and signal transduction, the role of Cavin-2 in vascular inflammation in the development of AAA is still unclear.

Purpose

To assess the influence of Cavin-2 deficiency in AAA development and clarify the role of Cavin-2 in the regulation of inflammatory cell adhesion in endothelial cells.

Methods

CaCl2-induced AAAs were induced by the periaortic application of 0.5 M CaCl2 in male SDPR-knockout (KO) and wild-type (WT) mice at 8–10 weeks of age. Angiotensin II (Ang II)-induced AAAs were created by 4-week-subcutaneous drug infusion in male ApoE-KO and ApoE/Cavin-2-double KO (DKO) mice at 24 weeks of age. Inflammatory response and cell adhesion were evaluated using human aortic endothelial cells (HAECs) and human monocytes (THP-1 cells).

Results

Six weeks after CaCl2 treatment, Cavin-2 deficiency significantly attenuated the development of AAAs. Elastin degradation was markedly suppressed and F4/80-positive macrophages infiltration in aortic walls were decreased in Cavin-2-KO mice. Although Ang II infusion for 4 weeks formed AAAs in ApoE KO mice and ApoE/Cavin-2-DKO mice, ApoE/Cavin-2-DKO mice exhibited the suppression of AAA formation independently of blood pressure. Immunohistochemical staining showed VCAM-1 expression on endothelial cells was suppressed in ApoE/Cavin-2-DKO mice. Further, in vitro co-culture experiment, the number of THP-1 cells adhered to TNF-treated SDPR-knockdown HAECs was decreased compared with that to control HAECs. Moreover, mRNA expression of VCAM-1 and ICAM-1 was decreased in TNFα-treated SDPR-knockdown HAECSs. Protein expression of VCAM-1 was also suppressed in TNFα-treated SDPR-knockdown HAECSs. The activity of NF-κB p65, an upstream regulator of VCAM-1 and ICAM-1,tended to be suppressed in TNFα-treated SDPR-knockdown HAECs.

Conclusion

In this study, we revealed that SDPR/Cavin-2 loss attenuated AAA development with the suppression of elastin degradation and macrophage infiltration. Our findings suggest that SDPR/Cavin-2 in the endothelial cells regulates the expression of adhesion molecules via NF-κB signaling and promotes the adhesion and infiltration of inflammatory cells to the aortic wall.

Funding Acknowledgement

Type of funding source: None

Ex Vivo assessment of competent strut coverage after coronary stenting by optical coherence tomography

Background

In many studies, struts coverage is defined as &gt;0 mm of tissue overlying the stent struts by optical coherence tomography (OCT). However, this definition has never been validated using histology as the “gold standard”. The present study sought to assess the appropriate cut-off value of neointimal thickness of stent strut coverage by OCT using histology.

Methods

OCT imaging was performed on 39 human coronary arteries with stents from 25 patients at autopsy. A total of 165 cross-sectional images from 46 stents were co-registered with histology. The optimal cut-off value of strut coverage by OCT was determined. Strut coverage by histology was defined as endothelial cells with at least underlying two layers of smooth muscle cells. Considering the resolution of OCT is 10–20 μm, 3 different cut-off values (i.e. at ≥20, ≥40, and ≥60 μm) were assessed.

Results

A total of 2235 struts were evaluated by histology. Eventually, 1216 struts which were well-matched struts were analyzed in this study. By histology, uncovered struts were observed in 160 struts and covered struts were observed in 1056 struts. The broadly used definition of OCT-coverage which does not consider neointimal thickness yielded a poor specificity of 37.5% and high sensitivity 100%. Of 3 cut-off values, the cut-off value of &gt;40 μm was more accurate as compared to &gt;20 and &gt;60 mm [sensitivity (99.3%), specificity (91.0%), positive predictive value (98.6%), and negative predictive value (95.6%)]

Conclusion

The most accurate cut-off value was ≥40 μm neointimal thickness by OCT in order to identify stent strut coverage validated by histology.

Funding Acknowledgement

Type of funding source: None

Three-Step Spin State Transition and Hysteretic Proton Transfer in the Crystal of an Iron(II) Hydrazone Complex

A proton-electron coupling system, exhibiting unique bistability or multistability of the protonated state, is an attractive target for developing new switchable materials based on proton dynamics. Herein, we present an iron(II) hydrazone crystalline compound, which displays the stepwise transition and bistability of proton transfer at the crystal level. These phenomena are realized through the coupling with spin transition. Although the multi-step transition with hysteresis has been observed in various systems, the corresponding behavior of proton transfer has not been reported in crystalline systems; thus, the described iron(II) complex is the first example. Furthermore, because proton transfer occurs only in one of the two ligands and π electrons redistribute in it, the dipole moment of the iron(II) complexes changes with the proton transfer, wherein the total dipole moment in the crystal was canceled out owing to the antiferroelectric-like arrangement.

Abstract 301: Cavin-2 Deletion Attenuates Fibroblast Activation and Cardiac Fibrosis via TGF-β Signaling by Interacting With Hsp90

Introduction: Heart failure (HF) is a progressive disease associated with high morbidity and mortality. A major cause of HF is the adverse tissue remodeling with interstitial fibrosis. Excessive extracellular matrix (ECM) accumulation is involved in the poor outcome. Transformation to myofibroblasts in resident fibroblasts has an important role for cardiac fibrosis on pressure-overload heart failure. TGF-β signaling is one of the critical pathways in fibroblast activation. Caveolae are major plasma membrane domain defined as 50-100 nm vesicular structures. Caveolins and cavins are known as caveolar-related proteins. TGF-β signaling is tightly connected with caveolae. A previous report shows that induction of Cav-1 expression leads to suppression of TGF-β signaling and an improvement of fibrosis. Although cavin-2/Serum deprivation response protein (SDPR) is also abundant in fibroblasts, the role of cavin-2 in cardiac fibrosis and function remains unknown.

Methods and Results: To clarify the role of cavin-2 in cardiac fibroblasts in the pressure-overloaded heart, we performed TAC operation on cavin-2 flox/flox mice and fibroblast-specific cavin-2 knockout (Postin Cre ; SDPR flox/flox ) mice (cavin-2 cKO). Four weeks after TAC, left ventricular fractional shortening (LVFS) was preserved with a significant reduction of cardiac fibrosis in cavin-2 cKO mice. Fibrosis-associated mRNA expression ( Col1a1, Ctgf, Col3 ) and α1 type I collagen deposition were reduced in the hearts of cavin-2-cKO mice after TAC. Transdifferentiation of fibroblasts into activated myofibroblasts is a defining feature of fibrosis. Myofibroblasts express αSMA and secrete ECM proteins via Smad signaling. αSMA-positive cells without showing vascular structure were reduced in cavin-2 cKO after TAC. In mouse embryonic fibroblasts (MEFs), cavin-2 deficiency reduced TGF-β1-induced αSMA production and fibrosis-associated mRNA expression. On the other hand, adenovirus-mediated cavin-2 overexpression significantly increased αSMA production and the fibrosis-associated mRNA expressions. Furthermore, TGF-β1-induced Smad2/3 phosphorylation was attenuated in cavin-2 KO MEFs compared to wild-type (WT) MEFs. A protein-Protein interaction screening using a promiscuous biotin ligase, called BioID, revealed that cavin-2 interacted with Hsp90ab1 and Hsp90b1 which modulate collagen synthesis through regulation of SMA and SMAD pathway. The protein expression level of Hsp90 in cavin-2 KO MEFs significantly decreased compared with that in WT MEFs.

Conclusions: Our observations suggest that cavin-2 contributes to the development of cardiac fibrosis through the differentiation from fibroblasts into myofibroblasts via TGF-β/Smad signaling. cavin-2 may be a novel therapeutic target for cardiac fibrosis.

Geometrical Evolution and Formation of the Photoproduct in the Cycloreversion Reaction of a Diarylethene Derivative Probed by Vibrational Spectroscopy

The front cover artwork is provided by the groups of Prof. Hiroshi Miyasaka (Osaka University, Japan), Prof. Masahiro Irie (Rikkyo University, Japan), Prof. Seiya Kobatake (Osaka City University, Japan) and Prof. Akira Sakamoto (Aoyama Gakuin University, Japan). The image shows the coherently vibrating closed form of a photochromic diarylethene derivative in the excited state, and subsequent structural evolution into the open form in the cycloreversion reaction. Read the full text of the Article at 10.1002/cphc.202000315.

Geometrical Evolution and Formation of the Photoproduct in the Cycloreversion Reaction of a Diarylethene Derivative Probed by Vibrational Spectroscopy

The geometrical evolution of the reactant and formation of the photoproduct in the cycloreversion reaction of a diarylethene derivative were probed using time-resolved absorption spectroscopies in the visible to near-infrared and mid-infrared regions. The time-domain vibrational data in the visible region show that the initially formed Franck-Condon state is geometrically relaxed into the minimum in the excited state potential energy surface, concomitantly with the low-frequency coherent vibrations. Theoretical calculations indicate that the nuclear displacement in this coherent vibration is nearly parallel to that in the geometrical relaxation. Time-resolved mid-infrared spectroscopy directly detected the formation of the open-ring isomer with the same time constant as the decrease of the closed-ring isomer in the excited state minimum. This observation reveals that no detectable intermediate, in which the population is accumulated, is present between the excited closed-ring isomer and the open-ring isomer in the ground state.

Photochromic Radical Complexes That Show Heterolytic Bond Dissociation

Photochromic materials have been widely used in various research fields because of their variety of photoswitching properties based on various molecular frameworks and bond breaking processes, such as homolysis and heterolysis. However, while a number of photochromic molecular frameworks have been reported so far, there are few reports on photochromic molecular frameworks that show both homolysis and heterolysis depending on the substituents with high durability. The biradicals and zwitterions generated by homolysis and heterolysis have different physical and chemical properties and different potential applications. Therefore, the rational photochromic molecular design to control the bond dissociation in the excited state on demand expands the versatility for photoswitch materials beyond the conventional photochromic molecular frameworks. In this study, we synthesized novel photochromic molecules based on the framework of a radical-dissociation-type photochromic molecule: phenoxyl-imidazolyl radical complex (PIC). While the conventional PIC shows the photoinduced homolysis, the substitution of a strong electron-donating moiety to the phenoxyl moiety enables the bond dissociation process to be switched from homolysis to heterolysis. This study gives a strategy for controlling the bond dissociation process of the excited state of photochromic systems, and the strategy enables us to develop further novel radical and zwitterionic photoswitches.

Observation of Proton Transfer Coupled Spin Transition and Trapping of Photoinduced Metastable Proton Transfer State in an Fe(II) Complex

An important technique to realize novel electron- and/or proton-based functionalities is to use a proton-electron coupling mechanism. When either a proton or electron is excited, the other one is modulated, producing synergistic functions. However, although compounds with proton-coupled electron transfer have been synthesized, crystalline molecular compounds that exhibit proton-transfer-coupled spin-transition (PCST) behavior have not been reported. Here, we report the first example of a PCST Fe(II) complex, wherein the proton lies on the N of hydrazone and pyridine moieties in the ligand at high-spin and low-spin Fe(II), respectively. When the Fe(II) complex is irradiated with light, intramolecular proton transfer occurs from pyridine to hydrazone in conjunction with the photoinduced spin transition via the PCST mechanism. Because the light-induced excited high-spin state is trapped at low temperatures in the Fe(II) complex-a phenomenon known as the light-induced excited-spin-state trapping effect-the light-induced proton-transfer state, wherein the proton lies on the N of hydrazone, is also trapped as a metastable state. The proton transfer was accomplished within 50 ps at 190 K. The bistable nature of the proton position, where the position can be switched by light irradiation, is useful for modulating proton-based functionalities in molecular devices.

Synthesis of Belt- and Möbius-Shaped Cycloparaphenylenes by Rhodium-Catalyzed Alkyne Cyclotrimerization

A belt-shaped [8]cycloparaphenylene (CPP) and an enantioenriched Möbius-shaped [10]CPP have been synthesized by high-yielding rhodium-catalyzed intramolecular cyclotrimerizations of a cyclic dodecayne and a pentadecayne, respectively. This Möbius-shaped [10]CPP possesses stable chirality and isolated with high enantiomeric purity. It is evident from the reaction Gibbs energy calculation that the above irreversible cyclotrimerizations are highly exothermic; therefore establishing that the intramolecular alkyne cyclotrimerization is a powerful route to strained cyclic molecular strips.

Abstract 520: Cavin-2/SDPR in Cardiac Fibroblasts Modulates TGF-β/Smad Signaling and Promotes Pressure Overload-induced Fibrosis

Introduction: Heart failure (HF) is a debilitating disease associated with high morbidity and mortality. The high mortality rate reflects the inadequacy of modern therapy and calls for new treatments. A major cause of HF is the adverse tissue remodeling with fibrosis. Excessive extracellular matrix (ECM) turnover is involved in the poor outcome. Resident fibroblasts are responsible for cardiac fibrosis on pressure-overload heart failure. Caveolins and Cavins are known as caveolar-related proteins. Caveolin-1 inhibits TGF-β1-induced fibrosis in the previous reports. Although Cavin-2/Serum deprivation response protein (SDPR), which is one of the caveolar-relatedproteins, is also abundant in fibroblasts, the role of Cavin-2 in cardiac fibrosis and function remains unknown.

Methods and Results: To clarify the role of Cavin-2 in the cardiac fibroblasts in the pressure-overloadedheart, we performed transverse aortic constriction (TAC) operation on SDPR flox/flox mice and fibroblast-specific Cavin-2 cKO mice (Postin Cre ; SDPR flox/flox ). Four weeks after TAC, left ventricular fractionalshortening (LVFS) was preservedwith a significant reduction of cardiac fibrosis in PostinCre; SDPRflox/flox mice. Fibrosis-associated mRNA expressions ( Col1a1 , Ctgf , Col3 ), α1 type I collagen deposition, and αSMA-positive cells were also reducedin the hearts of Cavin-2 cKO mice after TAC. Trans-differentiation of fibroblasts into activated myofibroblasts is a defining feature of fibrosis. Myofibroblasts express α-smooth muscle actin (αSMA) and secrete ECM proteins via Smad signaling. In mouse embryonic fibroblasts (MEFs),Cavin-2 deficiency reduced the levels of αSMA protein and fibrosis-associated mRNA expressions by TGF-β1 stimulation. Furthermore, TGF-β1-induced Smad2 phosphorylation was attenuatedin Cavin-2 KO MEFs compared to WT MEFs. On the other hand, adenovirus-mediated Cavin-2 overexpression significantly increased αSMA and the fibrosis-associated mRNA expressions.

Conclusions: Our observations suggest that Cavin-2 contributes to the development of cardiac fibrosis through the differentiation from fibroblasts into myofibroblasts via TGF-β/Smad signaling. Cavin-2 may be a novel therapeutic target for cardiac fibrosis.

Systems Network Genomic Analysis Reveals Cardioprotective Effect of MURC/Cavin-4 Deletion Against Ischemia/Reperfusion Injury

Background

Ischemia/reperfusion (I/R) injury is a critical issue in the development of treatment strategies for ischemic heart disease. MURC (muscle‐restricted coiled‐coil protein)/Cavin‐4 (caveolae‐associated protein 4), which is a component of caveolae, is involved in the pathophysiology of dilated cardiomyopathy and cardiac hypertrophy. However, the role of MURC in cardiac I/R injury remains unknown.

Methods and Results

The systems network genomic analysis based on PC‐corr network inference on microarray data between wild‐type and MURC knockout mouse hearts predicted a network of discriminating genes associated with reactive oxygen species. To demonstrate the prediction, we analyzed I/R‐injured mouse hearts. MURC deletion decreased infarct size and preserved heart contraction with reactive oxygen species–related molecule EGR1 (early growth response protein 1) and DDIT4 (DNA‐damage‐inducible transcript 4) suppression in I/R‐injured hearts. Because PC‐corr network inference integrated with a protein–protein interaction network prediction also showed that MURC is involved in the apoptotic pathway, we confirmed the upregulation of STAT3 (signal transducer and activator of transcription 3) and BCL2 (B‐cell lymphoma 2) and the inactivation of caspase 3 in I/R‐injured hearts of MURC knockout mice compared with those of wild‐type mice. STAT3 inhibitor canceled the cardioprotective effect of MURC deletion in I/R‐injured hearts. In cardiomyocytes exposed to hydrogen peroxide, MURC overexpression promoted apoptosis and MURC knockdown inhibited apoptosis. STAT3 inhibitor canceled the antiapoptotic effect of MURC knockdown in cardiomyocytes.

Conclusions

Our findings, obtained by prediction from systems network genomic analysis followed by experimental validation, suggested that MURC modulates cardiac I/R injury through the regulation of reactive oxygen species–induced cell death and STAT3‐meditated antiapoptosis. Functional inhibition of MURC may be effective in reducing cardiac I/R injury.

Electrochromism of fast photochromic radical complexes forming light-unresponsive stable colored radical cation

We demonstrated the electrochromism of photochromic radical complexes containing triaryl imidazole: fast photoswitchable pentaarylbiimidazole (PABI) and the phenoxyl-imidazolyl radical complex (PIC). Cyclic voltammetry and spectroelectrochemistry revealed that PABI and PIC generate the highly stable radical cation by one-electron oxidation accompanied by a color change from colorless to green. The stability of the radical cation is strongly affected by the dihedral angle between the imidazole ring and the phenyl ring at the 2-position of the imidazole ring.

Abstract OT2-02-01: A confirmation study of omitting axillary dissection in patients with breast cancer and positive sentinel nodes

Background

The omission of axillary dissection for positive sentinel-node breast cancer is considered the standard treatment for patients who undergo breast conserving surgery and radiation therapy, according to the results of ACOSOG-Z0011 and AMAROS trials. On the other hand, some surgeons still think that the surgical stress of axillary dissection is minimal, and dissection is permitted. Furthermore, Z0011 contains several problems, such as insufficient number of entry cases and lack of radiation field unity. Thus, we planned a prospective trial to confirm the safety of omitting axillary dissection in patients with breast cancer and positive sentinel nodes.

Trial design

This is a single arm, confirmation study of three medical centers. Prior to surgery, informed consent is obtained, and patients are registered primarily. After surgery, patients with 1 to 2 positive sentinel nodes, for whom axillary dissection was omitted, are finally included in this trial at final registration.

Eligibility criteria

Patients with histologically-diagnosed breast cancer, Tis–2, N0 based on a core needle biopsy, will be included in this trial. Eligible patients must be between 20 and 80 years of age, with a performance status of 0–2 and adequate organ function. They must not have undergone any prior operation, radiation therapy, chemotherapy, endocrine therapy, or immunotherapy.

Specific aims

The primary endpoint is 5-year (y) axillary recurrence rate. Secondary endpoints are 5-y overall survival, 5-y recurrence-free survival, 5-y local recurrence-free survival, the rate of upper-limb lymphedema, quality of life, and comparison of axillary recurrence rates between patients with two or more dissected nodes and those with only one positive node.

Statistical methods

The expected rate of axillary recurrence is 2.0%, and non-inferiority is defined as an axillary recurrence lesser than or equal to 5% in the axillary radiotherapy group. The sample size was calculated with a study power of 80% and type I error of 10% (two-sided). The required number of patients is estimated to be 189.

Present and target accrual

Patient accrual from the three medical centers was initiated in July 2016. We plan to enroll a total of 189 patients at final registration in this trial.

Citation Format: Jibiki N, Hirano A, Ochi T, Sakamoto A, Horiuchi K, Noguchi E, Omi Y, Ogura K, Inoue H, Kamio T, Naritaka Y, Fujibayashi M, Hiroshima K, Nagashima Y, Sakai S, Karasawa K, Okamoto T. A confirmation study of omitting axillary dissection in patients with breast cancer and positive sentinel nodes [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 OT2-02-01.