Somatic alteration and depleted nuclear expression of BAP1 in human esophageal squamous cell carcinoma

BRCA1‐associated protein 1 (BAP1) is a deubiquitinating enzyme that is involved in the regulation of cell growth. Recently, many somatic and germline mutations of BAP1 have been reported in a broad spectrum of tumors. In this study, we identified a novel somatic non‐synonymous BAP1 mutation, a phenylalanine‐to‐isoleucine substitution at codon 170 (F170I), in 1 of 49 patients with esophageal squamous cell carcinoma (ESCC). Multiplex ligation‐dependent probe amplification (MLPA) of BAP1 gene in this ESCC tumor disclosed monoallelic deletion (LOH), suggesting BAP1 alterations on both alleles in this tumor. The deubiquitinase activity and the auto‐deubiquitinase activity of F170I‐mutant BAP1 were markedly suppressed compared with wild‐type BAP1. In addition, wild‐type BAP1 mostly localizes to the nucleus, whereas the F170I mutant preferentially localized in the cytoplasm. Microarray analysis revealed that expression of the F170I mutant drastically altered gene expression profiles compared with expressed wild‐type BAP1. Gene‐ontology analyses indicated that the F170I mutation altered the expression of genes involved in oncogenic pathways. We found that one candidate, TCEAL7, previously reported as a putative tumor suppressor gene, was significantly induced by wild‐type BAP1 as compared to F170I mutant BAP1. Furthermore, we found that the level of BAP1 expression in the nucleus was reduced in 44% of ESCC examined by immunohistochemistry (IHC). Because the nuclear localization of BAP1 is important for its tumor suppressor function, BAP1 may be functionally inactivated in a substantial portion of ESCC. Taken together, BAP1 is likely to function as a tumor suppressor in at least a part of ESCC.     

Diagnostic value of endobronchial ultrasonography with a guide sheath for peripheral pulmonary lesions without X-ray fluoroscopy

STUDY OBJECTIVES: We evaluated the feasibility and efficacy of transbronchial biopsy (TBB) and bronchial brushing by endobronchial ultrasonography (EBUS) with a guide sheath (GS) as a guide for diagnosing peripheral pulmonary lesions (PPLs) without radiographic fluoroscopy. PATIENTS: One hundred twenty-one patients with 123 PPLs (mean diameter, 31.0 mm) whose bronchoscopic findings were normal. METHODS: An EBUS-GS was inserted and advanced to the PPL without fluoroscopy. Once we obtained the EBUS image, the probe was withdrawn and the GS was left in place. TBB and/or bronchial brushing were performed via the GS. When an EBUS image could not be obtained, we changed to the bronchoscopic examination under fluoroscopy. RESULTS: Seventy-six of 123 PPLs (61.8%) were diagnosed by EBUS-GS guidance without fluoroscopy. The diagnostic yield for PPLs > 20 mm in diameter (75.6%) was significantly higher than that for those 相似文献   

Dominant negative suppression of Rad leads to QT prolongation and causes ventricular arrhythmias via modulation of L-type Ca2+ channels in the heart

Disorders of L-type Ca2+ channels can cause severe cardiac arrhythmias. A subclass of small GTP-binding proteins, the RGK family, regulates L-type Ca2+ current (I(Ca,L)) in heterologous expression systems. Among these proteins, Rad (Ras associated with diabetes) is highly expressed in the heart, although its role in the heart remains unknown. Here we show that overexpression of dominant negative mutant Rad (S105N) led to an increase in I(Ca,L) and action potential prolongation via upregulation of L-type Ca2+ channel expression in the plasma membrane of guinea pig ventricular cardiomyocytes. To verify the in vivo physiological role of Rad in the heart, a mouse model of cardiac-specific Rad suppression was created by overexpressing S105N Rad, using the alpha-myosin heavy chain promoter. Microelectrode studies revealed that action potential duration was significantly prolonged with visible identification of a small plateau phase in S105N Rad transgenic mice, when compared with wild-type littermate mice. Telemetric electrocardiograms on unrestrained mice revealed that S105N Rad transgenic mice had significant QT prolongation and diverse arrhythmias such as sinus node dysfunction, atrioventricular block, and ventricular extrasystoles, whereas no arrhythmias were observed in wild-type mice. Furthermore, administration of epinephrine induced frequent ventricular extrasystoles and ventricular tachycardia in S105N Rad transgenic mice. This study provides novel evidence that the suppression of Rad activity in the heart can induce ventricular tachycardia, suggesting that the Rad-associated signaling pathway may play a role in arrhythmogenesis in diverse cardiac diseases.     

Prevention of catheter-related infections using a closed hub system in patients with pulmonary arterial hypertension.

BACKGROUND: Most of the patients with pulmonary arterial hypertension (PAH) receiving intravenous epoprostenol have experienced catheter-related infections during long-term treatment. Catheter hub was reported to be the most important source of catheter-related infections. To prevent the catheter-related infections, we have introduced a closed hub system and compared the incidence of catheter-related infections with that in patients using a non-closed hub system. METHODS AND RESULTS: We evaluated the results obtained on 24 occasions in 20 patients with PAH between June 1999 and December 2005. On 11 occasions, a non-closed hub system was used and on 13 cases a closed hub system. We classified the catheter-related infection into a catheter-related bloodstream infection (CRBSI) group or a tunnel infection group based on the pathway of bacteria. The CRBSI rate was 0.89 per 1,000 catheter days in the non-closed hub system group vs 0.10 per 1,000 catheter days in the closed hub system group. Kaplan-Meier analysis showed that the risk of CRBSI significantly decreased in the closed hub system group. None of the patients died as a direct consequence of catheter-related infection during the study period. CONCLUSIONS: We successfully prevented CRBSI by using a closed hub system.     

Severe Bleeding Tendency Caused by Leukemic Infiltration and Destruction of Vascular Walls in Chronic Neutrophilic Leukemia

Bleeding is reportedly one of the major causes of death in patients with chronic neutrophilic leukemia (CNL), but thrombocytopenia, abnormal platelet functions, or coagulopathy has been confirmed to be the cause of the bleeding tendency in only a small proportion of the patients. We report the case of a 49-year-old woman with CNL who experienced episodes of cutaneous and recurrent multiple cerebral hemorrhages without severe thrombocytopenia, detectable abnormal platelet functions, or coagulating dysfunction. Histological examination of specimens obtained at autopsy showed extensive infiltration and destruction of vascular walls by leukemic cells, which could explain her severe bleeding tendency. This study is the first to clearly show that the infiltration and destruction of vascular walls by leukemic cells can cause fatal bleeding episodes without warning from laboratory findings. Further studies are needed to elucidate the mechanism of the infiltration and destruction of blood vessels by CNL cells and to develop effective measures to control the growth and infiltration of CNL cells.     

Inducible nitric oxide synthase gene promoter polymorphism is associated with increased gastric mRNA expression of inducible nitric oxide synthase and increased risk of gastric carcinoma

BACKGROUND AND AIMS: Stimulation of inducible nitric oxide synthase gene expression by Helicobacter pylori, with subsequent overproduction of nitric oxide, has been implicated in gastric carcinogenesis. We investigated whether inducible nitric oxide synthase promoter gene polymorphisms are associated with (a) inducible nitric oxide synthase mRNA expression in the gastric mucosa, and (b) the risk of gastric carcinoma. MATERIALS AND METHODS: The relationship between gastric inducible nitric oxide synthase mRNA expression and inducible nitric oxide synthase promoter polymorphisms (CCTTT repeat polymorphism and -2445 C-->G SNP) was examined in 74 H. pylori-infected patients with gastric cancer, peptic ulcer, or functional dyspepsia. In a case-control study the prevalence of the polymorphisms was examined in H. pylori-infected gastric carcinomas (n=77) and noncancerous controls (n=154). RESULTS: Inducible nitric oxide synthase mRNA levels were significantly higher in long CCTTT repeat (either allele>11) carriers than in short ones (P=0.015). Multivariate regression analysis showed that inducible nitric oxide synthase mRNA expression was significantly linked to long CCTTT repeat and gastric cancer (P=0.026), but not to -2445 C-->G SNP and other parameters. The case-control study showed that long CCTTT repeat carriers had an increased risk of gastric cancer with an odds ratio of 2.0 (P=0.021). -2445 C-->G SNP was not associated with the risk. CONCLUSIONS: Helicobacter pylori induces higher inducible nitric oxide synthase mRNA expression in carriers of long CCTTT repeats of inducible nitric oxide synthase promoter, and this polymorphism is associated with an increased risk of gastric carcinoma.     

An Innovative Approach to Bone Marrow Collection and Transplantation in a Patient with β-Thalassemia Major: Marrow Collection Using a Perfusion Method Followed by Intra-Bone Marrow Injection of Collected Bone Marrow Cells

Using small animals (mice and rats) and monkeys, we have found that the combination of bone marrow collection using the perfusion method (PM) and intra-bone marrow-bone marrow transplantation (IBM-BMT) of the collected cells is safe and effective in treating various intractable diseases. Based on these findings, we attempted to apply this method to humans. We report here the first case of a patient (6 years old) with beta-thalassemia major who underwent allogeneic BMT using this new PM + IBM-BMT method. The white blood cell counts of the patient gradually increased to more than 1500/microL by day 47 and continued to increase, reaching the highest level (8600/microL) on day +55. Fluorescence in situ hybridization data on day +33 showed that 98% of the peripheral blood cells were from the donor. Notably, there were no symptoms of graft-versus-host disease (GvHD). However, on day +56, the patient regrettably died of asphyxia resulting from sticky sputum. There was no evidence of infection (in the lung or liver) or GvHD (in the skin) by necropsy. We hope that this case report will help make our new strategies more readily available for the treatment of patients with various intractable diseases.     

A study of factors influencing prognosis after resection of hepatic metastases from colorectal and gastric carcinoma

OBJECTIVE: The aim of this study is to determine the absolute contraindication for hepatic resection for colorectal metastases and investigate the value of hepatectomy for gastric metastases by comparing it with the results of colorectal metastases performed with the same criteria. METHODS: A retrospective cohort study was conducted in patients undergoing hepatic resection for metastatic colorectal (n = 64) and gastric (n = 17) carcinomas. Common predictive factors for both metastases were analyzed by the stratified Cox proportional hazard model. In this model, the different baseline hazard was set for each disease, whereas the risk of each covariate was assumed to be equal in both gastric and colorectal metastases. RESULTS: Overall 1-, 2-, and 5-yr survival rates after hepatectomy for colorectal and gastric metastases were 90%, 73%, 42%, and 47%, 22%, 0%, respectively. Factors controlling prognosis were as follows: age > or = 60, extrahepatic metastases, serosal invasion, grade of lymph node metastases, tumor cell differentiation of the primary lesion(s), carcinoembryonic antigen level, tumor-exposed surgical margin, and blood transfusion. In particular, presence of extrahepatic metastases showed the markedly high-risk ratio among these eight variables. CONCLUSIONS: Hepatectomy, if possible, is indicated in patients with hepatic metastases from colorectal carcinoma if there are no extrahepatic metastases and if the primary disease is controlled. It is indicated only in carefully selected patients with metastases from gastric carcinoma.