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1.
Oncogene ; 29(19): 2831-42, 2010 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-20190804

RESUMO

Cancer cells upregulate glycolysis, increasing glucose uptake to meet energy needs. A small fraction of a cell's glucose enters the hexosamine biosynthetic pathway (HBP), which regulates levels of O-linked beta-N-acetylglucosamine (O-GlcNAc), a carbohydrate posttranslational modification of diverse nuclear and cytosolic proteins. We discovered that breast cancer cells upregulate the HBP, including increased O-GlcNAcation and elevated expression of O-GlcNAc transferase (OGT), which is the enzyme catalyzing the addition of O-GlcNAc to proteins. Reduction of O-GlcNAcation through RNA interference of OGT in breast cancer cells leads to inhibition of tumor growth both in vitro and in vivo and is associated with decreased cell-cycle progression and increased expression of the cell-cycle inhibitor p27(Kip1). Elevation of p27(Kip1) was associated with decreased expression and activity of the oncogenic transcription factor FoxM1, a known regulator of p27(Kip1) stability through transcriptional control of Skp2. Reducing O-GlcNAc levels in breast cancer cells decreased levels of FoxM1 protein and caused a decrease in multiple FoxM1-specific targets, including Skp2. Moreover, reducing O-GlcNAcation decreased cancer cell invasion and was associated with the downregulation of matrix metalloproteinase-2, a known FoxM1 target. Finally, pharmacological inhibition of OGT in breast cancer cells had similar anti-growth and anti-invasion effects. These findings identify O-GlcNAc as a novel mechanism through which alterations in glucose metabolism regulate cancer growth and invasion and suggest that OGT may represent novel therapeutic targets for breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fatores de Transcrição Forkhead/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Proteínas Oncogênicas/metabolismo , Acetilglucosamina/metabolismo , Animais , Sequência de Bases , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Proteína Forkhead Box M1 , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , N-Acetilglucosaminiltransferases/antagonistas & inibidores , N-Acetilglucosaminiltransferases/deficiência , N-Acetilglucosaminiltransferases/genética , Invasividade Neoplásica/patologia , Fenótipo , Regulação para Cima/efeitos dos fármacos
2.
Transfusion ; 37(7): 719-26, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9225936

RESUMO

BACKGROUND: Transfusion-related acute lung injury (TRALI) is clinically similar to the adult respiratory distress syndrome (ARDS) and has been linked to the transfusion of leukocyte antibodies in blood components. Animal model have implicated neutrophil (PMN)-priming agents in ARDS; however, two agents were required. Previous studies showed the generation of PMN-priming agents during blood storage. Thus the association of PMN-priming agents with TRALI was examined. STUDY DESIGN AND METHODS: Ten patients with TRALI and 10 with febrile or urticarial reactions (control group) were evaluated. The presence of PMN-priming activity was tested in the patients' pretransfusion and posttransfusion blood samples by incubating PMNs with these samples followed by activation of the respiratory burst. Plasma lipids were separated by normal-phase high-performance liquid chromatography (HPLC), and the priming activity was evaluated. The presence of leukocyte antibodies was determined in the blood donors and patients with TRALI. RESULTS: Significantly more PMN-priming activity was present in the posttransfusion sera (11.4 +/- 1.8 nmol superoxide anion/min, mean +/- SEM; n = 10) and plasma of patients with TRALI than in their pretransfusion sera (6.5 +/- 1.5: n = 10) or in the pretransfusion and posttransfusion sera (5.1 +/- 1.3, n = 10; and 4.5 +/- 1.4, n = 10, respectively) and from the controls (p < 0.05). HPLC separation of lipids demonstrated that three active species were present in the posttransfusion plasma samples of TRALI patients. All the patients with TRALI had underlying clinical factors, such as infection, cytokine administration, recent surgery, or massive transfusion, while only 2 of 10 control patients had these clinical conditions. None of the donors had significant titers of HLA or HLA-DR antibodies; however, 50 percent had weak positivity for granulocyte antibodies. CONCLUSION: TRALI is the result of two clinical events, the first being a predisposing clinical condition and the second being the transfusion of biologically active lipids in stored blood.


Assuntos
Lipídeos/fisiologia , Pneumopatias/etiologia , Reação Transfusional , Adolescente , Adulto , Idoso , Anticorpos/análise , Doadores de Sangue , Criança , Pré-Escolar , Feminino , Granulócitos/imunologia , Antígenos HLA/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/fisiologia , Transfusão de Plaquetas/efeitos adversos , Síndrome do Desconforto Respiratório/etiologia , Estudos Retrospectivos , Condicionamento Pré-Transplante
3.
J Pediatr ; 127(6): 997-1000, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8523206

RESUMO

We describe a biopsy-confirmed case of acute interstitial nephritis associated with the use of loracarbef in an 18-month-old boy, which resulted in end-stage renal failure. This complication has been documented with the use of beta-lactam antibiotics, and it seems likely the loracarbef was responsible for acute interstitial nephritis in this patient.


Assuntos
Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Cefalosporinas/efeitos adversos , Cefalosporinas/uso terapêutico , Nefrite Intersticial/etiologia , Doença Aguda , Antibacterianos/administração & dosagem , Biópsia , Cefalosporinas/administração & dosagem , Humanos , Lactente , Rim/anormalidades , Rim/patologia , Rim/ultraestrutura , Masculino , Necrose/patologia , Otite Média/tratamento farmacológico
4.
Cancer ; 74(1): 203-16, 1994 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8004577

RESUMO

BACKGROUND: Abdominal pain in children receiving chemotherapy for cancer presents the clinician with unique problems due to the altered immunity of these patients or to the oncologic setting. The major clinical decisions regarding these patients are to determine if and when operative intervention is indicated. METHODS: A retrospective study was done to examine the clinical, radiographic, and laboratory findings that indicate the need for surgical intervention. Sixty-eight of 1090 children who underwent treatment for cancer from October 1982 to December 1990 developed abdominal complaints requiring them to be hospitalized. Nineteen of these patients underwent exploratory laparotomy (operative), and the other 49 were observed (nonoperative). RESULTS: No significant differences were observed in the phase of chemotherapy, treatment with vincristine or corticosteroids, or the hematologic indices between the operative and nonoperative groups. Eighteen of nineteen patients survived their surgeries. Seventeen (89%) of these laparotomies were positive based on the surgical pathology and the operative report. Peritoneal signs on physical examination (P < 0.001) or pneumatosis intestinalis on abdominal radiographs correlated with positive laparotomies (P = 0.001). CONCLUSIONS: Peritoneal signs on physical examination or pneumatosis intestinalis on abdominal X-rays were associated with and specific for the presence of acute surgical disease of the abdomen in immunocompromised pediatric oncology patients.


Assuntos
Abdome Agudo/cirurgia , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Abdome Agudo/complicações , Abdome Agudo/diagnóstico , Adolescente , Adulto , Apendicite/complicações , Apendicite/cirurgia , Criança , Pré-Escolar , Emergências , Feminino , Humanos , Hospedeiro Imunocomprometido , Laparotomia , Masculino , Neoplasias/complicações , Neoplasias/imunologia , Exame Físico , Pneumatose Cistoide Intestinal/diagnóstico por imagem , Radiografia , Estudos Retrospectivos
5.
Acta Neuropathol ; 86(4): 399-404, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8256592

RESUMO

An 8-month-old male infant who presented in the neonatal period with failure to thrive, bilateral pleural and pericardial effusions, and hepatic insufficiency characterized by elevated liver functions tests and hypoalbuminemia was found at autopsy to have an unusual combination of olivopontocerebellar atrophy (OPCA), micronodular cirrhosis, and renal tubular microcysts. Metabolic evaluation was significant only for elevated urine dicarboxylic acids. In the brain, sections from the cerebellum showed marked atrophy of folia most severe in the vermal and paravermal regions. In addition, mild neuronal loss was present in the basis pontis and inferior olivary nuclei accompanied by gliosis. Residual Purkinje cells in the cerebellar hemispheres exhibited greatly expanded and swollen arbors, which ultrastructurally were found to contain densely packed membranous cytoplasmic body-like inclusions that had the appearance of unwinding, lamellar coils. Review of the literature shows that this constellation of findings has been associated with carbohydrate-deficient transferrin. This biochemical marker along with the distinctive clinical presentation and pathological features clearly delineates a unique subset of OPCA.


Assuntos
Doenças Renais Císticas/patologia , Túbulos Renais/patologia , Cirrose Hepática/patologia , Atrofias Olivopontocerebelares/patologia , Cerebelo/patologia , Dendritos/ultraestrutura , Humanos , Lactente , Doenças Renais Císticas/genética , Cirrose Hepática/genética , Masculino , Atrofias Olivopontocerebelares/genética , Células de Purkinje/ultraestrutura , Síndrome
6.
Pediatr Pathol ; 11(1): 1-29, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2014185

RESUMO

Prune belly syndrome (PBS) has been recognized since 1950 as the triad of absent abdominal wall musculature, undescended testes, and urinary tract anomalies. The etiology, however, remains uncertain. Theories of mesenchymal maldevelopment, obstruction, and genetic origin have been proposed. To evaluate the role of lower urinary tract obstruction as it relates to prostatic development and PBS, we studied the lower urinary tract of 15 cases of PBS, 8 cases of posterior urethral valves (PUV), and 34 age-matched controls. It is generally accepted that prostatic growth and development are dependent on mesenchymal-epithelial interactions. We evaluated the mesenchymal and epithelial differentiation and relationships, and found distinctly different and consistent abnormalities between PBS and PUV as compared with one another and controls. The findings suggest that in PBS, prostatic growth and development are hindered because of destruction or absence of the appropriate primitive mesenchyme. Our studies could not definitely exclude very early obstruction as a cause of the findings because of lack of appropriate fetal material.


Assuntos
Próstata/crescimento & desenvolvimento , Síndrome do Abdome em Ameixa Seca/fisiopatologia , Uretra/anormalidades , Adulto , Desenvolvimento Embrionário e Fetal , Feto , Humanos , Imuno-Histoquímica , Recém-Nascido , Masculino , Próstata/embriologia , Próstata/patologia , Síndrome do Abdome em Ameixa Seca/etiologia , Síndrome do Abdome em Ameixa Seca/patologia , Valores de Referência , Uretra/patologia , Uretra/fisiopatologia
7.
J Clin Invest ; 79(6): 1868-73, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3495553

RESUMO

Single, preexposure, parenteral injection with both recombinant tumor necrosis factor/cachectin (TNF/C) and interleukin-1 (IL-1) prolonged the survival of rats (144 +/- 9 h) in continuous hyperoxia (greater than 99% O2 at 1 atm) when compared with rats injected with boiled TNF/C and boiled IL-1 (61 +/- 2 h), TNF/C alone (61 +/- 2 h), IL-1 alone (62 +/- 2 h), or saline (64 +/- 3 h). After exposure to hyperoxia for 52 h, pleural effusion volume, pulmonary artery pressure, total pulmonary resistance, and lung morphologic damage were decreased in those rats given TNF/C and IL-1 as compared with saline-injected rats. In parallel, ratios of reduced (GSH) to oxidized (GSSG) glutathione were greater (P less than 0.05) in lungs of TNF/C + IL-1-injected rats (91 +/- 20) than of saline-injected rats (30 +/- 4) that had been exposed to hyperoxia for 52 h. No differences were found in superoxide dismutase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase, or catalase activities in lungs of TNF/C + IL-1- or saline-treated, hyperoxia-exposed rats. Our results indicate that pretreatment with TNF/C and IL-1 favorably altered lung glutathione redox status, decreased lung injury, and enhanced survival of rats exposed to hyperoxia.


Assuntos
Glutationa/metabolismo , Glicoproteínas/farmacologia , Oxigenoterapia Hiperbárica/efeitos adversos , Interleucina-1/farmacologia , Pulmão/efeitos dos fármacos , Animais , Glicoproteínas/uso terapêutico , Oxigenoterapia Hiperbárica/mortalidade , Interleucina-1/uso terapêutico , Pulmão/metabolismo , Masculino , Oxirredução , Ratos , Ratos Endogâmicos , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Fator de Necrose Tumoral alfa
9.
J Infect Dis ; 131(3): 201-9, 1975 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-165241

RESUMO

Specific immunity developed by mice against protozoan (Toxoplasma gondii and Besnoitia jellisoni) and bacterial (Listeria monocytogenes) infections was compared with nonspecific protection conferred by prior infections. The results indicated that homologous immunity protected mice from more than 10-5 LD50 of T. gondii or B. jellisoni, but from only 10-2 LD50 of L. monocytogenes. Heterospecific protection among these organisms was for 10-0.4 minus 10-1.2 LD50. In studies in hamsters specific immunity to protozoan (T. gondii and B. jellisoni) and viral (equine Herpesvirus type 1 and Oriboca virus) infections was compared with nonspecific protection conferred by prior infections with several heterospecific agents: T. gondii; B. jellison; equine Herpesvirus type 1; Oriboca, Ossa, vesicular stomatitis, yellow fever, and Newcastle disease viruses; L. monocytogenes; and the bacillus Calmette-Guerin strain of Mycobacterium tuberculosis. The results indicated that homologous immunity in hamsters was effective against 10-6 minus 10-7 LD50 of T. gondii, B. jellisoni, equine Herpesvirus type 1, or Oriboca virus. Prior infection with Newcastle disease virus protected (probably by interferon induction) against 10-3 LD50 of equine Herpesvirus type 1. Heterospecific protection among other agents was for less than 10 LD50. This insignificant heterospecific protection in infections in which cellular immunity plays a role suggests that both the induction phase and the expression phase are specific.


Assuntos
Especificidade de Anticorpos , Imunidade , Listeriose/imunologia , Infecções por Protozoários/imunologia , Viroses/imunologia , Animais , Apicomplexa , Arbovírus/imunologia , Cricetinae , Feminino , Herpesviridae/imunologia , Imunidade Ativa , Imunidade Celular , Listeria monocytogenes/imunologia , Camundongos , Vírus da Doença de Newcastle/imunologia , Infecções por Protozoários/microbiologia , Toxoplasma/imunologia , Vírus da Estomatite Vesicular Indiana/imunologia , Vírus da Febre Amarela/imunologia
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