Tumor suppressive role of the epigenetic master regulator BRD3 in colorectal cancer.

Bromodomain and extraterminal domain (BET) family proteins are epigenetic master regulators of gene expression via recognition of acetylated histones and recruitment of transcription factors and co-activators to chromatin. Hence, BET family proteins have emerged as promising therapeutic targets in cancer. In this study, we examined the functional role of bromodomain containing 3 (BRD3), a BET family protein, in colorectal cancer (CRC). In vitro and vivo analyses using BRD3-knockdown or BRD3-overexpressing CRC cells showed that BRD3 suppressed tumor growth and cell cycle G1/S transition and induced p21 expression. Clinical analysis of CRC datasets from our hospital or The Cancer Genome Atlas revealed that BET family genes, including BRD3, were overexpressed in tumor tissues. In immunohistochemical analyses, BRD3 was observed mainly in the nucleus of CRC cells. According to single-cell RNA sequencing in untreated CRC tissues, BRD3 was highly expressed in malignant epithelial cells, and cell cycle checkpoint-related pathways were enriched in the epithelial cells with high BRD3 expression. Spatial transcriptomic and single-cell RNA sequencing analyses of CRC tissues showed that BRD3 expression was positively associated with high p21 expression. Furthermore, overexpression of BRD3 combined with knockdown of, a driver gene in the BRD family, showed strong inhibition of CRC cells in vitro. In conclusion, we demonstrated a novel tumor suppressive role of BRD3 that inhibits tumor growth by cell cycle inhibition in part via induction of p21 expression. BRD3 activation might be a novel therapeutic approach for CRC.

Convergent genomic diversity and novel BCAA metabolism in intrahepatic cholangiocarcinoma.

BACKGROUND: Driver alterations may represent novel candidates for driver gene-guided therapy; however, intrahepatic cholangiocarcinoma (ICC) with multiple genomic aberrations makes them intractable. Therefore, the pathogenesis and metabolic changes of ICC need to be understood to develop new treatment strategies. We aimed to unravel the evolution of ICC and identify ICC-specific metabolic characteristics to investigate the metabolic pathway associated with ICC development using multiregional sampling to encompass the intra- and inter-tumoral heterogeneity. METHODS: We performed the genomic, transcriptomic, proteomic and metabolomic analysis of 39-77 ICC tumour samples and eleven normal samples. Further, we analysed their cell proliferation and viability. RESULTS: We demonstrated that intra-tumoral heterogeneity of ICCs with distinct driver genes per case exhibited neutral evolution, regardless of their tumour stage. Upregulation of BCAT1 and BCAT2 indicated the involvement of 'Val Leu Ile degradation pathway'. ICCs exhibit the accumulation of ubiquitous metabolites, such as branched-chain amino acids including valine, leucine, and isoleucine, to negatively affect cancer prognosis. We revealed that this metabolic pathway was almost ubiquitously altered in all cases with genomic diversity and might play important roles in tumour progression and overall survival. CONCLUSIONS: We propose a novel ICC onco-metabolic pathway that could enable the development of new therapeutic interventions.

An infant with a vertical vein aneurysm in a supracardiac totally anomalous pulmonary venous connection.

Massive vertical vein aneurysm in a supracardiac total anomalous pulmonary venous connection is rare. Herein, vertical vein aneurysm with total anomalous pulmonary venous connection and additional pathological findings are reported in a young child.

A role for gorilla APOBEC3G in shaping lentivirus evolution including transmission to humans.

The APOBEC3 deaminases are potent inhibitors of virus replication and barriers to cross-species transmission. For simian immunodeficiency virus (SIV) to transmit to a new primate host, as happened multiple times to seed the ongoing HIV-1 epidemic, the viral infectivity factor (Vif) must be capable of neutralizing the APOBEC3 enzymes of the new host. Although much is known about current interactions of HIV-1 Vif and human APOBEC3s, the evolutionary changes in SIV Vif required for transmission from chimpanzees to gorillas and ultimately to humans are poorly understood. Here, we demonstrate that gorilla APOBEC3G is a factor with the potential to hamper SIV transmission from chimpanzees to gorillas. Gain-of-function experiments using SIVcpzPtt Vif revealed that this barrier could be overcome by a single Vif acidic amino acid substitution (M16E). Moreover, degradation of gorilla APOBEC3F is induced by Vif through a mechanism that is distinct from that of human APOBEC3F. Thus, our findings identify virus adaptations in gorillas that preceded and may have facilitated transmission to humans.

Fanconi Anemia Complementation Group E, a DNA Repair-Related Gene, Is a Potential Marker of Poor Prognosis in Hepatocellular Carcinoma.

INTRODUCTION: Fanconi anemia complementation group E (FANCE) is a Fanconi anemia (FA) pathway gene that regulates DNA repair. We evaluated the clinical relevance of FANCE expression in hepatocellular carcinoma (HCC). METHODS: First, the associations between the expression of FA pathway genes including FANCE and clinical outcomes in HCC patients were analyzed in 2 independent cohorts: The Cancer Genome Atlas (TCGA, n = 373) and our patient cohort (n = 53). Localization of FANCE expression in HCC tissues was observed by immunohistochemical staining. Gene set enrichment analysis (GSEA) and gene network analysis (SiGN_BN) were conducted using the TCGA dataset. Next, an in vitro proliferation assay was performed using FANCE-knockdown HCC cell lines (HuH7 and HepG2). The association between mRNA expression of FANCE and that of DNA damage response genes in HCC was analyzed using TCGA and Cancer Cell Line Encyclopedia datasets. Finally, the association between FANCE mRNA expression and overall survival (OS) in various digestive carcinomas was analyzed using TCGA data. RESULTS: FANCE was highly expressed in HCC cells. Multivariate analysis indicated that high FANCE mRNA expression was an independent factor predicting poor OS. GSEA revealed a positive relationship between enhanced FANCE expression and E2F and MYC target gene expression in HCC tissues. FANCE knockdown attenuated the proliferation of HCC cells, as well as reduced cdc25A expression and elevated histone H3 pSer10 expression. SiGN_BN revealed that FANCE mRNA expression was positively correlated with DNA damage response genes (H2A histone family member X and checkpoint kinase 1) in HCC tissues. Significant effects of high FANCE expression on OS were observed in hepatobiliary pancreatic carcinomas, including HCC. CONCLUSIONS: FANCE may provide a potential therapeutic target and biomarker of poor prognosis in HCC, possibly by facilitating tumor proliferation, which is mediated partly by cell cycle signaling activation.

Diagnostic Performance of High-Resolution Intravascular Ultrasound for Abnormal Post-Stent Findings After Stent Implantation　- A Comparison Study Between High-Resolution Intravascular Ultrasound and Optical Coherence Tomography.

BACKGROUND: High-resolution intravascular ultrasound (HR-IVUS) is the most recently developed IVUS technology, which allows the detailed assessment of intravascular structures. The aim of this study was to evaluate the diagnostic performance of HR-IVUS in the detection of abnormal post-stent findings.Methods and Results:Patients with acute coronary syndrome underwent both HR-IVUS and optical coherence tomography (OCT) for post-stent evaluations. Quantitative measurements for stented segments and qualitative assessments for abnormal post-stent findings (stent edge dissection, intrastent tissue protrusion, and incomplete stent apposition [ISA]) were performed. Forty-seven patients underwent both HR-IVUS and OCT after stent implantation. HR-IVUS identified a larger minimal lumen area and a larger minimal lumen diameter than OCT (6.66±1.98 mm2vs. 5.61±1.79 mm2and 2.87±0.42 mm vs. 2.63±0.43 mm, respectively; both P<0.001). The sensitivity of HR-IVUS for the identification of stent edge dissection, intrastent tissue protrusion, and ISA were 20.0%, 48.9%, and 27.2%, respectively. CONCLUSIONS: In terms of post-stent evaluation, the diagnostic performance of HR-IVUS remains insufficient. Abnormal post-stent findings might be underestimated when performing HR-IVUS due to its low sensitivity.

Independent predictors of discordance between the resting full-cycle ratio and fractional flow reserve.

The resting full-cycle ratio (RFR), a novel resting index, is well correlated with and shows good diagnostic accuracy to the fractional flow reserve (FFR). However, discordance results between the RFR and FFR have been observed to occur in about 20% of cases. This study aimed to clarify the prevalence and factors of discordant results between the RFR and FFR through a direct comparison of these values in daily clinical practice. A total of 220 intermediate coronary lesions of 156 consecutive patients with RFR and FFR measurements were allocated to four groups according to RFR and FFR cutoff values. We compared the angiographic, clinical, and hemodynamic variables among the groups. Discordant results between the RFR and FFR were observed in 19.6% of vessels, and the proportion of discordant results was significantly higher in the left main trunk and left anterior descending artery (LM + LAD) than in non-LAD vessels (25.2% vs. 12.3%, p = 0.006). In the multivariable regression analysis, LM + LAD location, hemodialysis, and peripheral artery disease were associated with a low RFR among patients with a high FFR. Conversely, the absence of diabetes mellitus and the presence of higher hemoglobin levels were associated with a higher RFR among patients with a low FFR. Specific angiographic and clinical characteristics such as LM + LAD location, hemodialysis, peripheral artery disease, and absence of diabetes mellitus and anemia can be independent predictors of physiologic discordance between the RFR and FFR.

Impact of antiplatelet therapy on tissue prolapse at super acute phase after stenting: serial OCT study in acute coronary syndrome patients.

Although drug-eluting stents have improved clinical outcomes, percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) remains a challenging procedure in terms of thrombus management. A new-generation P2Y12 receptor inhibitor, prasugrel, provides more rapid and potent antiplatelet action compared with clopidogrel. Prasugrel achieved significant reduction of ischemic events compared with clopidogrel in ACS. The aim of this optical coherence tomography (OCT) study was to evaluate temporal changes in tissue prolapse after stenting under different antiplatelet regimens (aspirin plus prasugrel or clopidogrel) in ACS patients. A total of 119 ACS patients were randomized to either prasugrel or clopidogrel at the time of PCI. OCT analysis was available in 119 patients at baseline (just after stenting), 77 patients at 2 weeks, and 62 patients at 4 months after stenting. Cross-sectional analysis for every 1 mm was performed at in-stent and adjacent reference segment. Tissue prolapse area was calculated by lumen area minus stent area within the stented segment. Baseline patient and procedural characteristics were not different between the prasugrel and clopidogrel groups. Tissue prolapse area was significantly lower in the prasugrel compared with the clopidogrel group after stenting (0.24 ± 0.23 vs. 0.36 ± 0.23 mm2, p = 0.003) and at 2 weeks (0.11 ± 0.13 vs. 0.19 ± 0.16 mm2, p = 0.005). However, there was no significant difference at 4 months. In conclusion, our study suggests prasugrel was effective in reducing tissue prolapse in the super acute phase in ACS patients compared with clopidogrel. However, the effect of tissue prolapse reduction was not different up to 4 months follow-up.

Interstitial lung disease associated with adjuvant and neoadjuvant chemotherapy in early breast cancer.

BACKGROUND: Interstitial lung disease (ILD) is a rare adverse event in patients receiving adjuvant or neoadjuvant chemotherapy (NAC) for breast cancer. Few studies have reported the frequency of ILD in detail, and only small numbers of cases have been described in the literature. Given these previous findings concerning ILD, we retrospectively examined the clinicopathological characteristics of five cases of ILD who had received epirubicin and cyclophosphamide (EC) and compared their findings with non-ILD cases. METHODS: The present single-center retrospective study included breast cancer patients who underwent adjuvant chemotherapy or NAC at our hospital between January 2014 and January 2021. RESULTS: Thirty-nine patients who had received EC for operable breast cancer were enrolled in this study. ILD developed 5 out of 39 patients (12.8%). The incidence of ILD in patients with non-dose-dense (dd) or dd chemotherapy was statistically significantly different (p = 0.0149). ILD occurred in three patients during dd EC treatment and two during weekly paclitaxel (wPTX) after dd EC. ILD was detected in one patient with high Krebs von den Lungen-6 (KL-6) levels, in two patients with continuous pyrexia, and in two patients from computed tomography imaging, which was taken to estimate the efficacy of chemotherapy, in two patients. Three of the 5 ILD patients underwent bronchoalveolar lavage, and 2 of these patients were diagnosed with Pneumocystis jirovecii pneumonia (PCP). There were no cases of serious ILD that required steroid pulse therapy. CONCLUSIONS: Dd chemotherapy may be associated with an increased ILD frequency, which may reflect developing PCP. Careful monitoring and a timely diagnosis are useful for detecting early-stage ILD.

Successful combination treatment with transcatheter balloon atrioseptostomy and bilateral pulmonary artery banding in a collapsed preterm neonate.

There has been an increase in the use of extracorporeal membrane oxygenation for severe neonatal cardiac failure. However, the frequency of complications is high, particularly in preterm and low-birth-weight neonates. Herein, we present combination treatment with transcatheter balloon atrioseptostomy and bilateral pulmonary artery banding in a collapsed preterm neonate. This strategy can be an alternative to circulatory support using extracorporeal membrane oxygenation.

[Primary Biliary Cholangitis Diagnosed with Spontaneous Bacterial Peritonitis after Gastrectomy for Gastric Cancer-A Case Report].

Spontaneous bacterial peritonitis is defined as an ascitic fluid infection without an evident intra-abdominal surgically treatable source. The diagnosis is established by a positive ascitic fluid bacterial culture and an ascitic fluid absolute polymorphonuclear leukocyte(PMN)count≥250 cells/µL. Here we report the case of 81-year-old female patient who was diagnosed with spontaneous bacterial peritonitis after gastrectomy for gastric cancer. The laparoscopic distal gastrectomy and D1+ lymph node dissection were performed for Stage Ⅰ gastric cancer, and the postoperative course was uneventful. The patient presented with abdominal pain and was hospitalized again on the third day from the discharge. Computed tomography showed an accumulation of ascites, and the ascitic fluid polymorphonuclear leukocyte count was 9,973 cells/µL. The patient was diagnosed with spontaneous bacterial peritonitis, and antibacterial agent was performed. Abdominal pain and accumulation of ascites had been improved, and the ascitic fluid polymorphonuclear leukocyte count had decreased clearly. The patient discharged on the 57th day from the operation. Spontaneous bacterial peritonitis after gastrectomy for gastric cancer was rare. We report this rare case, along with a discussion of the literature.

[A Case of Portal Vein Thrombosis Found during Postoperative Adjuvant Chemotherapy(CAPOX)after Laparoscopic Surgery for Rectal Cancer].

Portal vein thrombosis after laparoscopic colorectal cancer surgery is rare and sometimes lethal. We report a case of asymptomatic portal vein thrombosis found during postoperative adjuvant chemotherapy(CAPOX)after laparoscopic surgery for rectal cancer. A male patient in his 60s underwent postoperative adjuvant chemotherapy( CAPOX). The elevation of liver enzyme before the chemotherapy was moderate enough to start. The liver enzyme was increased mildly during the chemotherapy. Computed tomography 27 weeks after the operation revealed the thrombus from the main portal vein to the right branch and posterior branch, and atrophy of the lateral segment with narrowed left branch. Blood flow was confirmed to be maintained by ultrasonic Doppler. We decided to discontinue the chemotherapy and started anticoagulant therapy with Warfarin. Thrombosis was disappeared 2 weeks later, and liver function went back to normal range after 8 weeks. Liver dysfunction during chemotherapy should be noted not only for drug-induced liver damage, but also for the possibility of postoperative asymptomatic portal vein thrombosis.

[Robotic Surgery Can Complete Radical Surgery and Urinary Tract Reconstruction for Locally Advanced Rectal Cancer with Ureteral Invasion-A Case Report].

A 82-year-old man presented with diarrhea and fatigue. He had no past medical or surgical history except chronic renal failure. Locally advanced rectal cancer with invasion to left ureter was detected in computed tomography. Colonoscopy revealed a circular lesion 12 cm from the anal verge. Biopsy showed moderately differentiated adenocarcinoma. There was no sign of distal metastasis and we decided to conduct radical surgery. Robot-assisted laparoscopic lower anterior resection with partial resection of left ureter, and diverting ileostomy were carried out. Besides, urinary tract reconstruction of ureterocystoneostomy using Lich-Gregoir technique was conducted by urologists also with robot assistance. The pathological stage of the disease was pT4b(left ureter)N1bM0, pStage Ⅲc. The resection margin was secured and radical surgery was achieved. The patient was discharged on postoperative day 22nd without postoperative complication. He is alive without recurrence at 6 months after the operation.

[A Case of Laparoscopic High Anterior Resection for Rectal Cancer with Autosomal Dominant Polycystic Kidney Disease].

The case was a 61-year-old woman. She was diagnosed with autosomal dominant polycystic kidney disease(ADPKD)at the age of 38 and started hemodialysis at the age of 42. She was diagnosed with rectal cancer(RS)at the age of 61. Laparoscopic high anterior resection and D3 lymphadenectomy were carried out. Although the intra-abdominal space was limited by the huge renal cysts, laparoscopic surgery can be safely performed by arranging the port closer to the midline, taking the patient's position sufficiently, and using some useful tips. Laparoscopic surgery for the patient with ADPKD was considered a useful approach.

Clinical feasibility of resting full-cycle ratio as a unique non-hyperemic index of invasive functional lesion assessment.

The resting full-cycle ratio (RFR) is a new physiologic index to assess myocardial ischemia. RFR and fractional flow reserve (FFR), the conventionally used index, have not been directly compared in evaluating the entire cardiac cycle. Accordingly, we aimed to compare the diagnostic performance of RFR directly with FFR and clarify the clinical feasibility of RFR as a unique non-hyperemic index in evaluating the cardiac cycle. The diagnostic performance of RFR was compared with FFR using an automated online calculation software. A total of 156 consecutive patients with 220 intermediate lesions were enrolled. RFR showed significant correlation with FFR (r = 0.774, p < 0.001). RFR systole and RFR diastole did also with FFR (r = 0.918, p < 0.001, and r = 0.733, p < 0.001, respectively). With FFR < 0.80 as a reference standard, RFR showed good diagnostic accuracy (DA: 80.5%), similar DA between RFR systole and RFR diastole (79.6% and 87.5%, p = 0.58, respectively), and good DA in any lesion locations, especially in non-left anterior descending coronary artery (LAD) lesions (73.7% and 87.6% for LAD vs. non-LAD, p < 0.05, respectively). RFR is a feasible and reliable non-hyperemic index regardless of the difference in cardiac cycle in evaluating physiological lesion severity in daily practice.

[A Case of Neuroendocrine Carcinoma Treated with Salvage Surgery after Systemic Chemotherapy].

A man in his 50s was admitted to our hospital due to hematemesis.Esophagogastroduodenoscopy revealed an 8 cm type 2 gastric tumor.The tumor was histologically diagnosed as a neuroendocrine carcinoma.CT showed that the tumor had directly infiltrated the liver but there was no distant metastasis.We performed open distal gastrectomy, D2 lymph node dissection, partial hepatectomy, and cholecystectomy.Four months after the surgery, metastases of the right adrenal gland and dorsal part of the inferior vena cava were found.Although a significant tumor reduction was obtained by 12 courses of chemotherapy with CDDP plus CPT-11, this effective treatment was discontinued for the patient's convenience.Fifteen months after the surgery, metastasis of the right adrenal gland and dorsal part of inferior vena cava demonstrated re-growth without any further metastasis.After 4 courses of the same regimen, a partial response was obtained for the recurrences.As a salvage surgery, we performed open right adrenal gland and the lymph nodes of dorsal of IVC resection.The patient is alive without recurrence 1 year after the salvage surgery.

Experimental Adaptive Evolution of Simian Immunodeficiency Virus SIVcpz to Pandemic Human Immunodeficiency Virus Type 1 by Using a Humanized Mouse Model.

Human immunodeficiency virus type 1 (HIV-1), the causative agent of AIDS, originated from simian immunodeficiency virus from chimpanzees (SIVcpz), the precursor of the human virus, approximately 100 years ago. This indicates that HIV-1 has emerged through the cross-species transmission of SIVcpz from chimpanzees to humans. However, it remains unclear how SIVcpz has evolved into pandemic HIV-1 in humans. To address this question, we inoculated three SIVcpz strains (MB897, EK505, and MT145), four pandemic HIV-1 strains (NL4-3, NLCSFV3, JRCSF, and AD8), and two nonpandemic HIV-1 strains (YBF30 and DJO0131). Humanized mice infected with SIVcpz strain MB897, a virus phylogenetically similar to pandemic HIV-1, exhibited a peak viral load comparable to that of mice infected with pandemic HIV-1, while peak viral loads of mice infected with SIVcpz strain EK505 or MT145 as well as nonpandemic HIV-1 strains were significantly lower. These results suggest that SIVcpz strain MB897 is preadapted to humans, unlike the other SIVcpz strains. Moreover, viral RNA sequencing of MB897-infected humanized mice identified a nonsynonymous mutation in env, a G413R substitution in gp120. The infectivity of the gp120 G413R mutant of MB897 was significantly higher than that of parental MB897. Furthermore, we demonstrated that the gp120 G413R mutant of MB897 augments the capacity for viral replication in both in vitro cell cultures and humanized mice. Taken together, this is the first experimental investigation to use an animal model to demonstrate a gain-of-function evolution of SIVcpz into pandemic HIV-1.IMPORTANCE From the mid-20th century, humans have been exposed to the menace of infectious viral diseases, such as severe acute respiratory syndrome coronavirus, Ebola virus, and Zika virus. These outbreaks of emerging/reemerging viruses can be triggered by cross-species viral transmission from wild animals to humans, or zoonoses. HIV-1, the causative agent of AIDS, emerged by the cross-species transmission of SIVcpz, the HIV-1 precursor in chimpanzees, around 100 years ago. However, the process by which SIVcpz evolved to become HIV-1 in humans remains unclear. Here, by using a hematopoietic stem cell-transplanted humanized-mouse model, we experimentally recapitulate the evolutionary process of SIVcpz to become HIV-1. We provide evidence suggesting that a strain of SIVcpz, MB897, preadapted to infect humans over other SIVcpz strains. We further demonstrate a gain-of-function evolution of SIVcpz in infected humanized mice. Our study reveals that pandemic HIV-1 has emerged through at least two steps: preadaptation and subsequent gain-of-function mutations.

Correction: HIV-1 competition experiments in humanized mice show that APOBEC3H imposes selective pressure and promotes virus adaptation.

[This corrects the article DOI: 10.1371/journal.ppat.1006348.].

HIV-1 competition experiments in humanized mice show that APOBEC3H imposes selective pressure and promotes virus adaptation.

APOBEC3 (A3) family proteins are DNA cytosine deaminases recognized for contributing to HIV-1 restriction and mutation. Prior studies have demonstrated that A3D, A3F, and A3G enzymes elicit a robust anti-HIV-1 effect in cell cultures and in humanized mouse models. Human A3H is polymorphic and can be categorized into three phenotypes: stable, intermediate, and unstable. However, the anti-viral effect of endogenous A3H in vivo has yet to be examined. Here we utilize a hematopoietic stem cell-transplanted humanized mouse model and demonstrate that stable A3H robustly affects HIV-1 fitness in vivo. In contrast, the selection pressure mediated by intermediate A3H is relaxed. Intriguingly, viral genomic RNA sequencing reveled that HIV-1 frequently adapts to better counteract stable A3H during replication in humanized mice. Molecular phylogenetic analyses and mathematical modeling suggest that stable A3H may be a critical factor in human-to-human viral transmission. Taken together, this study provides evidence that stable variants of A3H impose selective pressure on HIV-1.

Diagnostic Performance of High-Resolution Intravascular Ultrasound for the Detection of Plaque Rupture in Patients With Acute Coronary Syndrome.

BACKGROUND: The new 60-MHz high-resolution intravascular ultrasound (HR-IVUS) is the next-generation IVUS technology, providing higher image resolution than conventional IVUS. It gives clear images of plaque morphology and can discriminate the underlying mechanism of acute coronary syndrome (ACS). Our study aimed to evaluate the diagnostic performance of 60-MHz HR-IVUS in the detection of plaque rupture in patients with ACS.Methods and Results:Patients with ACS who underwent percutaneous coronary intervention for de novo native coronary artery lesions were enrolled. Both HR-IVUS and optical coherence tomography (OCT) were performed for the culprit lesions prior to interventions other than aspiration thrombectomy. Keeping plaque rupture detected by OCT as the gold standard, the diagnostic performance of HR-IVUS was evaluated. Overall, 70 patients underwent both HR-IVUS and OCT examinations. Of these, imaging assessments by HR-IVUS were available for all 70 patients (100%), and those by OCT were available for 54 patients (77.1%). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of HR-IVUS for identifying a plaque rupture were 84.8%, 57.1%, 75.7%, 70.6%, and 74.1%, respectively. CONCLUSIONS: HR-IVUS had high sensitivity, but modest specificity for identifying OCT-derived plaque rupture. Compared with results from previous conventional IVUS studies, HR-IVUS might have increased ability to detect OCT-derived plaque rupture, but there is still substantial scope for improvement, especially in the specificity.