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Heat-shock protein 5 (HSPA5) is a marker for poor prognosis in breast cancer patients and has an important role in cancer progression, including promoting drug resistance and metastasis. In this study, we identify that the specific lysine residue 447 (K447) of HSPA5 could be modified with polyubiquitin for subsequent degradation through the ubiquitin proteasomal system, leading to the suppression of cell migration and invasion of breast cancer. We further found that GP78, an E3 ubiquitin ligase, interacted with the C-terminal region of HSPA5 and mediated HSPA5 ubiquitination and degradation. Knock down of GP78 significantly increased the expression of HSPA5 and enhanced migration/invasive ability of breast cancer cells. Knock down of histone deacetylase-6 (HDAC6) increased the acetylation of HSPA5 at lysine residues 353 (K353) and reduced GP78-mediated ubiquitination of HSPA5 at K447 and then increased cell migration/invasion. In addition, we demonstrate that E3 ubiquitin ligase GP78 preferentially binds to deacetylated HSPA5. Notably, the expression levels of GP78 inversely correlated with HSPA5 levels in breast cancer patients. Patients with low GP78 expression significantly correlated with invasiveness of breast cancer, advanced tumor stages and poor clinical outcome. Taken together, our results provide new mechanistic insights into the understanding that deacetylation of HSPA5 by HDAC6 facilitates GP78-mediated HSPA5 ubiquitination and suggest that post-translational regulation of HSPA5 protein is critical for HSPA5-mediated metastatic properties of breast cancer.
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Neoplasias de la Mama/metabolismo , Proteínas de Choque Térmico/metabolismo , Histona Desacetilasas/metabolismo , Acetilación , Secuencia de Aminoácidos , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Chaperón BiP del Retículo Endoplásmico , Femenino , Técnicas de Silenciamiento del Gen , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/genética , Histona Desacetilasa 6 , Histona Desacetilasas/genética , Humanos , Ratones SCID , Datos de Secuencia Molecular , Invasividad Neoplásica , Metástasis de la Neoplasia , Complejo de la Endopetidasa Proteasomal/metabolismo , Homología de Secuencia de Aminoácido , UbiquitinaciónRESUMEN
BACKGROUND: Acute renal failure (ARF) is a life-threatening entity that frequently complicates advanced liver disease. This study documents a number of factors that may predispose to or precipitate ARF and influence outcomes in patients with advanced liver disease. Comparisons are also made between subgroups of patients with viral and alcohol-induced liver cirrhosis in those with ARF. PATIENTS AND METHODS: We conducted a retrospective chart review over one year of 127 consecutive hospital admissions in 82 patients who were diagnosed with advanced liver cirrhosis (Child-Pugh Class C) in a tertiary care center. A diagnosis of ARF was made in 29 admissions and another 98 admissions not complicated by ARF served as controls. This study evaluated different etiologies of ARF and developed a database which included clinical features, biochemical parameters, the etiology of cirrhosis, possible predisposing factors, and precipitating events. Version II of the Acute Physiology and Chronic Health Physiology Scoring system (APACHE II) was applied to predict short-term hospital mortality rates. RESULTS: ARF occurred in 29 admissions over the one-year study period (23%). The mean age of these patients was 56.8 +/- 12.0 years, and 73% were men. The patients with ARF had significant hyponatremia and higher levels of serum bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and white cell counts on admission than the controls. Patients who developed ARF were more likely to have had infection, especially septicemia, and gastrointestinal (GI) bleeding. Mortality rate in the patients with ARF was much higher than in those patients without ARF (72% vs. 13%, p < 0.001). The patients with viral cirrhosis and ARF were found to have higher leukocyte counts, serum bilirubin levels, and more frequent incidence of infection, septicemia and GI bleeding compared to the patients with alcoholic liver cirrhosis and ARF. Those with viral hepatitis were also significantly older and had more frequent incidence of ascites, but had lower levels of gamma-glutamyl transpeptidase and less frequent incidence of encephalopathy. CONCLUSIONS: The risk of ARF is significantly increased in patients with advanced liver cirrhosis presenting with marked hyperbilirubinemia, hyponatremia, elevated liver enzymes, infection, and GI bleeding. The presence of ARF leads to higher mortality rates in both viral and alcohol-induced liver cirrhosis.
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Lesión Renal Aguda/etiología , Cirrosis Hepática/complicaciones , Lesión Renal Aguda/epidemiología , Bilirrubina/sangre , Femenino , Hemorragia Gastrointestinal/complicaciones , Hepatitis Viral Humana/complicaciones , Humanos , Hiponatremia/complicaciones , Infecciones/complicaciones , Recuento de Leucocitos , Cirrosis Hepática/mortalidad , Cirrosis Hepática Alcohólica/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Sepsis/complicaciones , Transaminasas/sangreRESUMEN
Hemophagocytic syndrome (HPS) in systemic lupus erythematosus(SLE) patients has not commonly been reported. In this case study, we report the first case of Mycobacterium avium complex (MAC)-associated hemophagocytic syndrome in a patient with systemic lupus erythematosus (SLE). This SLE patient, a 15-year-old girl, had been on a high dose of prednisolone (> 0.5mg/kg/day) for more than 3 years. She presented with a spiking fever, hepatosplenomegaly, pancytopenia, hyperferritinemia and adult respiratory distress syndrome. Bone marrow examination revealed hemophagocytosis as well as non-caseating granulomatosis. There was no indication of SLE fare-up. She responded poorly to initial treatment with methyl-prednisolone, intravenous immumoglobulin, etoposide, and drugs for Mycobacterium tuberculosis including rifampin, ethambutol, isoniazid and pyramide. However, gastric lavage culture revealed MAC. Following treatment with clarithromycin, ciprofloxacin and amikacin, her condition gradually improved and she was discharged 3 months after admission. In SLE patients with pancytopenia and hyperferritinemia, MAC-associated HPS should be considered in the differential diagnosis.
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Histiocitosis de Células no Langerhans/microbiología , Lupus Eritematoso Sistémico/complicaciones , Mycobacterium avium , Tuberculosis Osteoarticular/complicaciones , Adolescente , Médula Ósea/microbiología , Médula Ósea/patología , Femenino , Histiocitosis de Células no Langerhans/patología , Humanos , Tuberculosis Osteoarticular/patologíaRESUMEN
BACKGROUND: Kawasaki disease is a common acquired heart disease in children. Only a few reports have been published concerning Kawasaki disease in infants. This study was performed to assess the clinical spectrum of Kawasaki disease in infants. METHODS: Between January 1989 and December 1998, a total of 48 consecutive Kawasaki patients less than one year of age were enrolled and studied retrospectively. Coronary artery dilation was defined as the internal diameter of a coronary artery larger than 3 mm. All cases received 2 gm/Kg of intravenous immunoglobulin. We divided the patients into two groups; group I; coronary artery dilation (+) and group II; coronary artery dilation (-), and compared the clinical and laboratory data. RESULTS: Of 273 patients with Kawasaki disease, 48 (17.5%) were less than one year of age. Among these patients (< 1 year old), the median age was 7.8 +/- 2.8 months (range 2 months to 12 months), and the male to female ratio was 1.52:1. The incidence of atypical Kawasaki disease was 31.2% (compared with an incidence of atypical Kawasaki disease among patient more than one year of age of 7.5%; p < 0.001), and that of coronary artery dilation was 35.4%. Clinical manifestations included fever 100%, extremity change 91.6%, skin rash 89.6%, conjunctivitis 89.6%, oral mucosa change 89.6%, and cervical lymphadenopathy 0%. Laboratory data revealed white blood cell count: 15,403 +/- 6,282/mm3, hemoglobin: 10.1 +/- 1.0 gm/dl, neutrophil: 59.2 +/- 13.7%, lymphocytes: 30.6 +/- 13.1%, platelet count: 456,3000 +/- 216,4000/mm3, and C-reactive protein 8.2 +/- 5.6 mg/dl. Patients with coronary artery dilation had a longer duration of diagnosis, higher incidence of atypical presentation, lower incidence of conjunctivitis, lower incidence of skin rash, lower incidence of extremity change, and lower C-reactive protein. The predictive value of coronary artery dilation based on the combination of atypical presentation, duration of diagnosis, and C-reactive protein was 81.2%. CONCLUSIONS: Kawasaki disease in infants is associated with a high incidence of atypical presentation and increased risk of coronary artery dilation. We suggest that in an infant with insufficient diagnostic criteria for Kawasaki disease, care should be taken to avoid missing atypical Kawasaki disease. Echocardiography is an important tool for diagnosis of atypical Kawasaki disease.
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Vasos Coronarios/fisiopatología , Síndrome Mucocutáneo Linfonodular/fisiopatología , Vasodilatación , Proteína C-Reactiva/análisis , Femenino , Humanos , Lactante , MasculinoRESUMEN
N-trans- and N-cis-Feruloyltyramines were isolated as the inhibitors of in vitro prostaglandin (PG) synthesis from an Indonesian medicinal plant, Ipomoea aquatica (Convolvulaceae). In order to clarify structure activity relationships, cinnamoyl-beta-phenethylamines with possible combinations of naturally occurring cinnamic acids and beta-phenethylamines were synthesized and tested for their inhibitory activities against PG synthetase and arachidonate 5-lipoxygenase. The compounds containing catechol groups such as N-caffeoyl-beta-phenethylamine (CaP) showed higher inhibitory effects on PG synthetase. The catechol group was found to be essential for the inhibition of arachidonate 5-lipoxygenase. The investigation of concentration dependent effects on PG biosynthesis revealed that CaP enhanced PG biosynthesis at a lower concentration range, whereas it inhibited the reaction at a higher concentration. The effects of CaP on each reaction step were investigated with purified PG endoperoxide synthase and microsomal PG synthetase. CaP inhibited the cyclooxygenase reaction, while it enhanced the hydroperoxidase reaction. N-Acyldopamines which contain catechol and lipophylic group were synthesized from dopamine and fatty acids to test their inhibitory effects on arachidonate 5-lipoxygenase. N-Linoleoyldopamine was the most active compound and its IC50 value was 2.3 nM in our assay system, in which an IC50 value of AA 861, a specific inhibitor of 5-lipoxygenase, was 8 nM.