Proximal ligation technique prevents thrombus formation in the pulmonary vein stump after lobectomy.

PURPOSE: To assess the risk factors for thrombosis in the pulmonary vein stump (PVT) and the efficacy of proximal ligation in preventing PVT after lobectomy. METHODS: In total, 649 surgical patients with lung cancer were retrospectively reviewed. To compare the clinical effectiveness of PV proximal ligation, the simple stapler group (290 patients) and the proximal ligation group (359 patients who underwent thread ligation at the pericardial reflection with/without a stapler) were analyzed. RESULTS: In the simple stapler group, 12 of 290 patients (4.1%) developed PVT. Among these, 9 of 58 underwent left upper lobectomy (LUL). In contrast, 5 of the 359 patients (1.4%) in the proximal ligation group developed PVT. All five patients received LUL. The incidence of PVT in the proximal ligation group was significantly lower than that in the simple stapler group (p = 0.0295) as well as in the analysis by LUL alone (p = 0.0263). A logistic regression analysis indicated that higher BMI and LUL were associated with the development of PVT (p = 0.0031, p < 0.0001), and PV proximal ligation reduced PVT (p = 0.0055). CONCLUSION: Proximal ligation of the PV has the potential to prevent PVT, especially after LUL.

Prostanoids Regulate Angiogenesis and Lymphangiogenesis in Pathological Conditions.

Angiogenesis, the formation of new blood vessels from the preexistent microvasculature, is an essential component of wound repair and tumor growth. Nonsteroidal anti-inflammatory drugs that suppress prostanoid biosynthesis are known to suppress the incidence and progression of malignancies including colorectal cancers, and also to delay the wound healing. However, the precise mechanisms are not fully elucidated. Accumulated results obtained from prostanoid receptor knockout mice indicate that a prostaglandin E-type receptor signaling EP3 in the host microenvironment is critical in tumor angiogenesis inducing vascular endothelial growth factor A (VEGF-A). Further, lymphangiogenesis was also enhanced by EP signaling via VEGF-C/D inductions in pathological settings. These indicate the importance of EP receptor to facilitate angiogenesis and lymphangiogenesis in vivo. Prostanoids act beyond their commonly understood activities in smooth muscle contraction and vasoactivity, both of which are quick responses elicited within several seconds on stimulations. Prostanoid receptor signaling will be a potential therapeutic target for disease conditions related to angiogenesis and lymphangiogenesis.

KUS121, a VCP modulator, has an ameliorating effect on acute and chronic heart failure without calcium loading via maintenance of intracellular ATP levels.

AIMS: As heart failure (HF) progresses, ATP levels in myocardial cells decrease, and myocardial contractility also decreases. Inotropic drugs improve myocardial contractility but increase ATP consumption, leading to poor prognosis. Kyoto University Substance 121 (KUS121) is known to selectively inhibit the ATPase activity of valosin-containing protein, maintain cellular ATP levels, and manifest cytoprotective effects in several pathological conditions. The aim of this study is to determine the therapeutic effect of KUS121 on HF models. METHODS AND RESULTS: Cultured cell, mouse, and canine models of HF were used to examine the therapeutic effects of KUS121. The mechanism of action of KUS121 was also examined. Administration of KUS121 to a transverse aortic constriction (TAC)-induced mouse model of HF rapidly improved the left ventricular ejection fraction and improved the creatine phosphate/ATP ratio. In a canine model of high frequency-paced HF, administration of KUS121 also improved left ventricular contractility and decreased left ventricular end-diastolic pressure without increasing the heart rate. Long-term administration of KUS121 to a TAC-induced mouse model of HF suppressed cardiac hypertrophy and fibrosis. In H9C2 cells, KUS121 reduced ER stress. Finally, in experiments using primary cultured cardiomyocytes, KUS121 improved contractility and diastolic capacity without changing peak Ca2+ levels or contraction time. These effects were not accompanied by an increase in cyclic adenosine monophosphate or phosphorylation of phospholamban and ryanodine receptors. CONCLUSIONS: KUS121 ameliorated HF by a mechanism totally different from that of conventional catecholamines. We propose that KUS121 is a promising new option for the treatment of HF.

A case of a systemic cancer-associated thrombosis successfully treated with multi-disciplinary treatment including anticoagulation therapy and anticancer drug therapy.

Background: Cancer-associated thrombosis (CAT) is one of the major complications during the treatment course of cancer, which often challenges clinicians in daily clinical practice despite anticoagulation therapy. Case summary: A 57-year-old man with a history of a liver transplantation was diagnosed with post-transplant lymphoproliferative disorders. He developed severe systemic thromboses including a massive pulmonary embolism and was treated with anticoagulation therapy including a factor Xa inhibitor. However, the systemic thromboses worsened despite the anticoagulation therapy. During the acute treatment course of the thromboses, we administered anticancer drug therapy in hopes of an improvement in the activity of the cancer status leading to a favourable effect on the thrombosis status. Multi-disciplinary treatment including anticoagulation therapy and anticancer drug therapy successfully improved the systemic thrombosis. Discussion: Anticoagulation therapy is a standard treatment for CAT; however, some cases of CAT do not successfully improve despite anticoagulation therapy, partly due to a highly active cancer status. Anticancer drug therapy might increase the risk of a thrombosis, whereas it could improve the activity of the cancer status leading to a decreased risk of a thrombosis. A multi-disciplinary therapy might be a reasonable option especially for CAT with a highly active cancer status.

A biologically active lipid, thromboxane, as a regulator of angiogenesis and lymphangiogenesis.

Thromboxane (TX) and prostaglandins are metabolites of arachidonic acid, a twenty-carbon unsaturated fatty acid, and have a variety of actions that are exerted via specific receptors. Angiogenesis is defined as the formation of new blood vessels from pre-existing vascular beds and is a critical component of pathological conditions, including inflammation and cancer. Lymphatic vessels play crucial roles in the regulation of interstitial fluid, immune surveillance, and the absorption of dietary fat from the intestine; and they are also involved in the pathogenesis of various diseases. Similar to angiogenesis, lymphangiogenesis, the formation of new lymphatic vessels, is a critical component of pathological conditions. The TP-dependent accumulation of platelets in microvessels has been reported to enhance angiogenesis under pathological conditions. Although the roles of some growth factors and cytokines in angiogenesis and lymphangiogenesis have been well characterized, accumulating evidence suggests that TX induces the production of proangiogenic and prolymphangiogenic factors through the activation of adenylate cyclase, and upregulates angiogenesis and lymphangiogenesis under disease conditions. In this review, we discuss the role of TX as a regulator of angiogenesis and lymphangiogenesis, and its emerging importance as a therapeutic target.

Bile Collected From the Normal Gallbladder of Patients During Surgery Has Simple Bacterial Flora.

Background Bile inhibits bacterial growth because it is rich in bacteriostatic compounds such as bile acids. Analytical techniques using a high-intensity sequencer recently revealed bacterial flora in the bile of normal gallbladders in brain-dead patients. Therefore, we performed a microbial flora analysis of bile collected from pathologically normal gallbladders surgically removed from patients with hepatobiliary pancreatic diseases and normal liver function. Methods Bacterial DNA was extracted from bile samples and analyzed using 16S rRNA sequencing. Results The culture results of all 12 bile samples were negative. However, the results of the 16S ribosome gene analysis suggested the presence of bacterial flora in all samples. The phyla Firmicutes, Proteobacteria, Actinobacteria, and, more specifically, the genera Anaerobacillus, Delftia, Bacillus, Ralstonia, Ochrobactrum, Acidovorax, and Curvibacter were detected in all 12 samples. The results of the 16S rRNA gene profile analysis revealed that Anaerobacillus and Delftia accounted for 58.62%-87.63% of the bacteria identified in each sample. Conclusion In a bacterial flora analysis targeting the 16S ribosomal gene, a specific bacterial flora was detected in bile collected from the pathologically normal gallbladders of patients with hepatobiliary pancreatic diseases. Although a diverse bacterial flora was previously reported in the bile of brain-dead patients, the present results revealed a simple bacterial flora with no diversity in the bile samples.

Impact of ischemia on left atrial remodeling and dysfunction in swine models of mitral regurgitation.

Left atrial (LA) dysfunction is one of the predictive factors of worse outcomes after mitral valve surgery for mitral regurgitation (MR). We aimed to investigate the effect of MR etiology on progression of LA remodeling in swine MR models. MR was induced in 14 Yorkshire pigs using catheter-based procedures. Seven pigs underwent simultaneous occlusions of the left circumflex artery and the diagonal branch, which resulted in ischemic mitral regurgitation (IMR group). The other seven pigs underwent chordal severing to induce leaflet prolapse simulating degenerative mitral regurgitation (DMR group). Changes in LA volume and function were assessed at baseline, 1 mo, and 3 mo using echocardiography and hemodynamic evaluations. Histopathological assessments were conducted to evaluate LA hypertrophy and fibrosis. At 3 mo, quantitative MR severity was comparable and severe in both groups. Despite the similar degree of MR, minimum LA volume index increased significantly more in the IMR group (IMR: 11.9 ± 6.4 to 73.2 ± 6.4 mL/m2, DMR: 10.7 ± 6.4 to 29.5 ± 6.4 mL/m2, Pinteraction = 0.004). Meanwhile, increase in maximum LA volume index was similar between the groups, resulting in lower LA emptying function in the IMR group (IMR: 60.1 ± 3.1 to 29.4 ± 3.1%; DMR: 62.4 ± 3.1 to 58.2 ± 3.1%, Pinteraction = 0.0003). LA reservoir strain assessed by echocardiography was also significantly lower in the IMR group. Histological analyses revealed increased LA cellular hypertrophy and fibrosis in the IMR group. In conclusion, ischemic MR is associated with aggressive remodeling and reduced emptying function compared with the MR due to leaflet prolapse. Earlier intervention might be necessary for ischemic MR to prevent LA remodeling.NEW & NOTEWORTHY We show different LA structural and functional remodeling patterns between ischemic MR and MR due to leaflet prolapse. Severe ischemic MR was accompanied by extensive LA remodeling, which may be associated with poor clinical outcomes. Our data suggest that detailed structural and functional LA remodeling assessment is important for managing IMR and to determine the presence of LA ischemia.

Analysis of appendectomy samples identified dysbiosis in acute appendicitis.

Appendicitis is the most common cause of sudden-onset abdominal pain requiring surgery. Culture-independent techniques have revealed that the complex intestinal bacterial ecology is associated with various diseases. To evaluate differences in patient characteristics and gut microbiota distribution in patients with appendicitis, we enrolled 12 patients who underwent appendectomy for appendicitis (appendicitis group) and 13 patients who underwent ileocecal resection or right hemicolectomy for colon cancer (control group). Microbiota were analyzed using next-generation sequencing of surgical specimens from appendix swab samples collected postoperatively. Overall differences in the structure of the gut microbiota were evaluated using the α- and ß-diversity indices, which were calculated using the weighted or unweighted UniFrac distance. Changes in the gut microbial distribution were taxonomically evaluated at the phylum and genus levels. The α-diversity of observed species was significantly different between patients with and without inflammation of the appendix. The appendiceal microbiome of patients with appendicitis exhibited the highest unweighted UniFrac distances. There were no significant differences at the phylum level. Ruminococcus (p=0.02) and f_erysipelotrichaceae_g_clostridium (p=0.005) were increased in the control group compared with the appendicitis group. This pilot study provides the first report of the correlation of the gut microbiota with the pathogenesis of appendicitis evaluated using mucus-origin sampling.

Periprocedural Stroke After Coronary Revascularization (from the CREDO-Kyoto PCI/CABG Registry Cohort-3).

There is a scarcity of data on incidence, risk factors, especially clinical severity, and long-term prognostic impact of periprocedural stroke after coronary revascularization in contemporary real-world practice. Among 14,867 consecutive patients undergoing first coronary revascularization between January 2011 and December 2013 (percutaneous coronary intervention [PCI]: N = 13258, and coronary artery bypass grafting [CABG]: N = 1609) in the Coronary Revascularization Demonstrating Outcome Study in Kyoto PCI/CABG registry Cohort-3, we evaluated the details on periprocedural stroke. Periprocedural stroke was defined as stroke within 30 days after the index procedure. Incidence of periprocedural stroke was 0.96% after PCI and 2.13% after CABG (log-rank p <0.001). Proportions of major stroke defined by modified Rankin Scale ≥2 at hospital discharge were 68% after PCI, and 77% after CABG. Independent risk factors of periprocedural stroke were acute coronary syndrome (ACS), carotid artery disease, advanced age, heart failure, and end-stage renal disease after PCI, whereas they were ACS, carotid artery disease, atrial fibrillation, chronic obstructive pulmonary disease, malignancy, and frailty after CABG. There was excess long-term mortality risk of patients with periprocedural stroke relative to those without after both PCI and CABG (hazard ratio 1.71 [1.25 to 2.33], and hazard ratio 4.55 [2.79 to 7.43]). In conclusion, incidence of periprocedural stroke was not negligible not only after CABG, but also after PCI in contemporary real-world practice. Majority of patients with periprocedural stroke had at least mild disability at hospital discharge. ACS and carotid artery disease were independent strong risk factors of periprocedural stroke after both PCI and CABG. Periprocedural stroke was associated with significant long-term mortality risk after both PCI and CABG.

Rapid HER2 cytologic fluorescence in situ hybridization for breast cancer using noncontact alternating current electric field mixing.

BACKGROUND: Human epidermal growth factor receptor 2-in situ hybridization (HER2-ISH) is widely approved for diagnostic, prognostic biomarker testing of formalin-fixed paraffin-embedded tissue blocks. However, cytologic ISH analysis has a potential advantage in tumor samples such as pleural effusion and ascites that are difficult to obtain the histological specimens. Our aim was to evaluate the clinical reliability of a novel rapid cytologic HER2 fluorescence ISH protocol (rapid-CytoFISH). MATERIALS AND METHODS: Using a new device, we applied a high-voltage/frequency, noncontact alternating current electric field to tissue imprints and needle rinses, which mixed the probe within microdroplets as the voltage was switched on and off (AC mixing). Cytologic samples (n = 143) were collected from patients with immunohistochemically identified HER2 breast cancers. The specimens were then tested using standard dual-color ISH using formalin-fixed paraffin-embedded tissue (FFPE-tissue DISH) for HER2-targeted therapies, CytoFISH, and rapid-CytoFISH (completed within 4 h). RESULTS: All 143 collected cytologic specimens (50 imprinted cytology specimens from resected tumors and 93 liquid-based cytology specimens from needle rinses) were suitable for FISH analysis. The HER2/chromosome enumeration probe (CEP) 17 ratios did not significantly differ between FFPE-tissue DISH and either CytoFISH protocol. Based on HER2 scoring criteria, we found 95.1% agreement between FFPE-tissue DISH and CytoFISH (Cohen's kappa coefficient = 0.771 and 95% confidence interval (CI): 0.614-0.927). CONCLUSION: CytoFISH could potentially serve as a clinical tool for prompt determination of HER2 status in breast cancer cytology. Rapid-CytoFISH with AC mixing will enable cancer diagnoses and HER2 status to be determined on the same day a patient comes to a clinic or hospital.

Lionheart LincRNA alleviates cardiac systolic dysfunction under pressure overload.

Recent high-throughput approaches have revealed a vast number of transcripts with unknown functions. Many of these transcripts are long noncoding RNAs (lncRNAs), and intergenic region-derived lncRNAs are classified as long intergenic noncoding RNAs (lincRNAs). Although Myosin heavy chain 6 (Myh6) encoding primary contractile protein is down-regulated in stressed hearts, the underlying mechanisms are not fully clarified especially in terms of lincRNAs. Here, we screen upregulated lincRNAs in pressure overloaded hearts and identify a muscle-abundant lincRNA termed Lionheart. Compared with controls, deletion of the Lionheart in mice leads to decreased systolic function and a reduction in MYH6 protein levels following pressure overload. We reveal decreased MYH6 results from an interaction between Lionheart and Purine-rich element-binding protein A after pressure overload. Furthermore, human LIONHEART levels in left ventricular biopsy specimens positively correlate with cardiac systolic function. Our results demonstrate Lionheart plays a pivotal role in cardiac remodeling via regulation of MYH6.

Emergence and Spread of Carbapenem-Resistant and Aminoglycoside-Panresistant Enterobacter cloacae Complex Isolates Coproducing NDM-Type Metallo-ß-Lactamase and 16S rRNA Methylase in Myanmar.

Surveillance of 10 hospitals and a regional public health laboratory in Myanmar identified 31 isolates of carbapenem-resistant Enterobacter cloacae complex harboring blaNDM-type Of these isolates, 19 were highly resistant to aminoglycosides and harbored one or more genes encoding 16S rRNA methylases, including armA, rmtB, rmtC, and/or rmtE Of the 19 isolates, 16 were Enterobacter xiangfangensis ST200, with armA on the chromosome and a plasmid harboring blaNDM-1 and rmtC, indicating that these isolates were clonally disseminated nationwide in Myanmar.IMPORTANCE The emergence of multidrug-resistant E. cloacae complex has become a public health threat worldwide. E. xiangfangensis is a recently classified species belonging to E. cloacae complex. Here, we report a clonal dissemination of multidrug-resistant E. xiangfangensis ST200 producing two types of New Delhi metallo-ß-lactamase (NDM-type MBL), NDM-1 and -4, and three types of 16S rRNA methylases, ArmA, RmtC, and RmtE, in hospitals in Myanmar. The observation of these multidrug-resistant E. xiangfangensis ST200 isolates stresses the urgency to continue molecular epidemiological surveillance of these pathogens in Myanmar and in South Asian countries.

Development of a Novel One-Step Automated Rapid in situ Hybridization for Anaplastic Lymphoma Kinase Rearrangement Using Non-Contact Alternating-Current Electric-Field Mixing.

Echinoderm microtubule-associated protein-like 4 and anaplastic lymphoma kinase (ALK) fusion gene rearrangement is a key driver mutation in non-small cell lung cancer (NSCLC). Although Break-Apart ALK fluorescence in situ hybridization (FISH) is a reliable diagnostic method for detecting ALK gene rearrangement, it is also costly and time-consuming to use as a routine screening test. Our aim was to evaluate the clinical utility of a novel one-step, automated, rapid FISH (Auto-RaFISH) method developed to facilitate hybridization. This method takes advantage of the non-contact mixing effect of an alternating-current electric field. Ten representative specimens from 85 patients diagnosed at multiple centers with primary lung cancer with identified ALK-FISH status were collected. The specimens were all tested using FISH, RaFISH, and Auto-RaFISH. With both RaFISH protocols, the ALK test was completed within 4.5 h, as compared to the 20 h needed for the standard protocol. We found 100% agreement between the standard FISH, RaFISH, and new Auto-RaFISH based on the ALK status, and all methods stained equally well. These findings suggest that Auto-RaFISH could potentially serve as an automated clinical tool for prompt determination of ALK status in NSCLC.

Discovery of a new pyrimidine synthesis inhibitor eradicating glioblastoma-initiating cells.

BACKGROUND: Glioblastoma-initiating cells (GICs) comprise a tumorigenic subpopulation of cells that are resistant to radio- and chemotherapies and are responsible for cancer recurrence. The aim of this study was to identify novel compounds that specifically eradicate GICs using a high throughput drug screening approach. METHODS: We performed a cell proliferation/death-based drug screening using 10 560 independent compounds. We identified dihydroorotate dehydrogenase (DHODH) as a target protein of hit compound 10580 using ligand-fishing and mass spectrometry analysis. The medical efficacy of 10580 was investigated by in vitro cell proliferation/death and differentiation and in vivo tumorigenic assays. RESULTS: Among the effective compounds, we identified 10580, which induced cell cycle arrest, decreased the expression of stem cell factors in GICs, and prevented tumorigenesis upon oral administration without any visible side effects. Mechanistic studies revealed that 10580 decreased pyrimidine nucleotide levels and enhanced sex determining region Y-box 2 nuclear export by antagonizing the enzyme activity of DHODH, an essential enzyme for the de novo pyrimidine synthesis. CONCLUSION: In this study, we identified 10580 as a promising new drug against GICs. Given that normal tissue cells, in particular brain cells, tend to use the alternative salvage pathway for pyrimidine synthesis, our findings suggest that 10580 can be used for glioblastoma therapy without side effects.Key Points1. Chemical screening identified 10580 as a novel GIC-eliminating drug that targets DHODH, an essential enzyme for the de novo pyrimidine synthesis pathway. 2. Compound 10580 induced cell cycle arrest, apoptosis, and differentiation in GICs.

Decline in Left Ventricular Ejection Fraction During Follow-Up in Patients With Severe Aortic Stenosis.

OBJECTIVES: The aim of this study was to investigate the prognostic impact of the decline in left ventricular ejection fraction (LVEF) at 1-year follow-up in patients with severe aortic stenosis (AS) managed conservatively. BACKGROUND: No previous study has explored the association between LVEF decline during follow-up and clinical outcomes in patients with severe AS. METHODS: Among 3,815 patients with severe AS enrolled in the multicenter CURRENT AS (Contemporary Outcomes After Surgery and Medical Treatment in Patients With Severe Aortic Stenosis) registry in Japan, 839 conservatively managed patients who underwent echocardiography at 1-year follow-up were analyzed. The primary outcome measure was a composite of AS-related deaths and hospitalization for heart failure. RESULTS: There were 91 patients (10.8%) with >10% declines in LVEF and 748 patients (89.2%) without declines. Left ventricular dimensions and the prevalence of valve regurgitation and atrial fibrillation or flutter significantly increased in the group with declines in LVEF. The cumulative 3-year incidence of the primary outcome measure was significantly higher in the group with declines in LVEF than in the group with no decline (39.5% vs. 26.5%; p < 0.001). After adjusting for confounders, the excess risk of decline in LVEF over no decline for the primary outcome measure remained significant (hazard ratio: 1.98; 95% confidence interval: 1.29 to 3.06). When stratified by LVEF at index echocardiography (≥70%, 60% to 69%, and <60%), the risk of decline in LVEF on the primary outcome was consistently seen in all the subgroups, without any interaction (p = 0.77). CONCLUSIONS: Patients with severe AS with >10% declines in LVEF at 1 year after diagnosis had worse AS-related clinical outcomes than those without declines in LVEF under conservative management. (Contemporary Outcomes After Surgery and Medical Treatment in Patients With Severe Aortic Stenosis Registry; UMIN000012140).

Cardioprotective Effects of VCP Modulator KUS121 in Murine and Porcine Models of Myocardial Infarction.

No effective treatment is yet available to reduce infarct size and improve clinical outcomes after acute myocardial infarction by enhancing early reperfusion therapy using primary percutaneous coronary intervention. The study showed that Kyoto University Substance 121 (KUS121) reduced endoplasmic reticulum stress, maintained adenosine triphosphate levels, and ameliorated the infarct size in a murine cardiac ischemia and reperfusion injury model. The study confirmed the cardioprotective effect of KUS121 in a porcine ischemia and reperfusion injury model. These findings confirmed that KUS121 is a promising novel therapeutic agent for myocardial infarction in conjunction with primary percutaneous coronary intervention.

Effect of lidocaine cream analgesia for chest drain tube removal after video-assisted thoracoscopic surgery for lung cancer: a randomized clinical trial.

BACKGROUND AND OBJECTIVES: Pain management makes an important contribution to good respiratory care and early recovery after thoracic surgery. Although the development of video-assisted thoracoscopic surgery (VATS) has led to improved patient outcomes, chest tube removal could be distressful experience for many patients. The aim of this trial was to test whether the addition of lidocaine cream would have a significant impact on the pain treatment during chest tube removal from patients who had undergone VATS for lung cancer. METHODS: This clinical trial was a double-blind randomized study. Forty patients with histologically confirmed lung cancer amenable to lobectomy/segmentectomy were enrolled. All patients had standard perioperative care. Patients were randomly assigned to receive either epidural anesthesia plus placebo cream (placebo, Group P) or epidural anesthesia plus 7% lidocaine cream cutaneously around the chest tube insertion site and on the skin over the tube's course 20 min (Group L) before chest drain removal. RESULTS: Visual analog scale (VAS) scores were higher in Group P (median 5, IQR, 3.25-8) than in Group L (median 2, IQR, 1-3). Pain intensities measured using a PainVision system were also higher in Group P (median 296.7, IQR, 216.9-563.5) than Group L (median 41.2, IQR, 11.8-97.0). VAS scores and the pain intensity associated with chest drain removal were significantly lower in Group L than Group P (p=0.0002 vs p<0.0001). CONCLUSION: Analgesia using lidocaine cream is a very simple way to reduce the pain of chest tube removal after VATS. TRIAL REGISTRATION NUMBER: UMIN000013824.

The ubiquitin-specific protease USP17 prevents cellular senescence by stabilizing the methyltransferase SET8 and transcriptionally repressing p21.

Su(var)3-9, Enhancer-of-zeste, and Trithorax (SET) domain-containing protein 8 (SET8) is the sole enzyme that monomethylates Lys-20 of histone H4 (H4K20). SET8 has been implicated in the regulation of multiple biological processes, such as gene transcription, the cell cycle, and senescence. SET8 quickly undergoes ubiquitination and degradation by several E3 ubiquitin ligases; however, the enzyme that deubiquitinates SET8 has not yet been identified. Here we demonstrated that ubiquitin-specific peptidase 17-like family member (USP17) deubiquitinates and therefore stabilizes the SET8 protein. We observed that USP17 interacts with SET8 and removes polyubiquitin chains from SET8. USP17 knockdown not only decreased SET8 protein levels and H4K20 monomethylation but also increased the levels of the cyclin-dependent kinase inhibitor p21. As a consequence, USP17 knockdown suppressed cell proliferation. We noted that USP17 was down-regulated in replicative senescence and that USP17 inhibition alone was sufficient to trigger cellular senescence. These results reveal a regulatory mechanism whereby USP17 prevents cellular senescence by removing ubiquitin marks from and stabilizing SET8 and transcriptionally repressing p21.

[A Case of Laparoscopic Gastric Local Resection for Dedifferentiated Gastric Liposarcoma].

A 73 year-old-woman visited our emergency department with a sudden stomach ache. A 7 cm tumor was found on the greater curvature side of the stomach by contrast-enhanced CT, and showed mosaic pattern when visualized with a contrast agent. An esophagogastroduodenoscopy showed normal mucosal gastric surface with compression findings by the gastric submucosal tumor, and therefore she was admitted to our department for surgery. Abdominal ultrasound revealed an uneven gastric submucosal tumor containing cystic components with a clear border, and gastric GIST was suspected due to its appearance, and therefore, laparoscopic gastric local resection was performed. The gastric tumor was located on the dorsal side of the greater curvature and adhered highly to the retroperitoneum and spleen. The omental incision was conducted first, and the adhesion around the tumor was carefully detached, following which wedge resection was performed using Endo-GIA®at the base of the tumor. The pathological findings of the resected specimens were mainly spindle-shaped tumor cells rich in polymorphism with a high degree of necrosis, and did not seem to be conclusively GIST; as such, various immunological tests were performed.c -kit(-), DOG-1(-), S-100 p(-), desmin(-), a-SMA(focal+), p16(+), MDM2(+), CDK4(+) results led to the diagnosis of dedifferentiated liposarcoma. The patient is currently being followed up with and is alive without recurrence 10 months after the operation.

miR-146a Suppresses SUMO1 Expression and Induces Cardiac Dysfunction in Maladaptive Hypertrophy.

RATIONALE: Abnormal SUMOylation has emerged as a characteristic of heart failure (HF) pathology. Previously, we found reduced SUMO1 (small ubiquitin-like modifier 1) expression and SERCA2a (sarcoplasmic reticulum Ca2+-ATPase) SUMOylation in human and animal HF models. SUMO1 gene delivery or small molecule activation of SUMOylation restored SERCA2a SUMOylation and cardiac function in HF models. Despite the critical role of SUMO1 in HF, the regulatory mechanisms underlying SUMO1 expression are largely unknown. OBJECTIVE: To examine miR-146a-mediated SUMO1 regulation and its consequent effects on cardiac morphology and function. METHODS AND RESULTS: In this study, miR-146a was identified as a SUMO1-targeting microRNA in the heart. A strong correlation was observed between miR-146a and SUMO1 expression in failing mouse and human hearts. miR-146a was manipulated in cardiomyocytes through AAV9 (adeno-associated virus serotype 9)-mediated gene delivery, and cardiac morphology and function were analyzed by echocardiography and hemodynamics. Overexpression of miR-146a reduced SUMO1 expression, SERCA2a SUMOylation, and cardiac contractility in vitro and in vivo. The effects of miR-146a inhibition on HF pathophysiology were examined by transducing a tough decoy of miR-146a into mice subjected to transverse aortic constriction. miR-146a inhibition improved cardiac contractile function and normalized SUMO1 expression. The regulatory mechanisms of miR-146a upregulation were elucidated by examining the major miR-146a-producing cell types and transfer mechanisms. Notably, transdifferentiation of fibroblasts triggered miR-146a overexpression and secretion through extracellular vesicles, and the extracellular vesicle-associated miR-146a transfer was identified as the causative mechanism of miR-146a upregulation in failing cardiomyocytes. Finally, extracellular vesicles isolated from failing hearts were shown to contain high levels of miR-146a and exerted negative effects on the SUMO1/SERCA2a signaling axis and hence cardiomyocyte contractility. CONCLUSIONS: Taken together, our results show that miR-146a is a novel regulator of the SUMOylation machinery in the heart, which can be targeted for therapeutic intervention.