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1.
Mol Carcinog ; 48(7): 633-41, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19072763

RESUMEN

Our previous study showed a characteristic p53 mutational spectrum in lung tumors from lung cancer patients in the Western Pennsylvania region. To further understand the involvement of p53 mutations in lung tumor development, in this study we compared p53 mutational spectra and distribution between tumor cells taken from lung tumor tissue and histologically normal cells taken from tumor-surrounding tissue obtained from 122 lung cancer patients [67 adenocarcinomas (ACs) and 55 squamous cell carcinomas (SCCs)]. Overall, mutations were detected in exons 5-8 of the p53 gene in cell samples from 39.3% (48/122) of the patients. Twenty-four mutations were found among the ACs (35.8%, 24/67) and consisted mostly of G to T transversions at codon 248 in either only the tumor tissue (12 cases, 50%), or only the histologically normal tissue (2 cases, 8.3%), or both tissue types (10 cases, 41.7%). Among the SCCs, 24 mutations of both transition and transversion types were detected at multiple codons in either only the tumor tissue (17 cases, 70.8%), or only the histologically normal tissue (3 cases, 12.5%), or both tissues (4 cases, 16.7%). Overall, the distribution of mutations among the tumor tissue and histologically normal tissue was not significantly different between the ACs and SCCs (P > 0.05). In both groups, the mutations in the histologically normal tissue may be identical to or different from those in the tumor tissue. Therefore, p53 mutations are frequent in tumor-surrounding histologically normal tissue, and some of them might be involved in lung carcinogenesis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Genes p53 , Neoplasias Pulmonares/genética , Pulmón/metabolismo , Mutación , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
2.
Leuk Lymphoma ; 49(9): 1738-44, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18798108

RESUMEN

We sought to determine the clinical and immunohistopathological prognostic factors for overall survival (OS) in adult patients with post-transplant lymphoproliferative disorders (PTLDs). Eighty-four patients diagnosed with PTLDs between 1980 and 2004 at the University of Pittsburgh Medical Center were identified. Immunohistochemical staining was performed on tumor tissue at the time of diagnosis for the following proteins: Bcl-2, Bcl-6, c-myc and p53. The median survival for all patients was 20.8 months, 95% CI: (7.4-77.6). On univariate analysis for OS, the following poor prognostic factors were identified: age at transplant >60 years (p = 0.024), multiorgan transplant (p = 0.019), ECOG > 2 (p < 0.0001), grafted organ involvement (p < 0.0001), extranodal disease (p = 0.011), early (<1 year) PTLDs (p < 0.0001), stage IV (p = 0.0017), EBV positive (p = 0.012) and elevated white blood count (p = 0.010). Good prognostic factors included ECOG<2 (p < 0.0001), late (>1 year) PTLDs (p = 0.002), early stage at diagnosis (stages I and II, p = 0.005), nodal disease (p = 0.0053), monomorphic disease (0.0034), initial immunosuppression reduction (p = 0.0015) and use of rituximab (p = 0.045). Bcl-2 but not Bcl-6, c-myc, or p53 correlated with poor survival, p = 0.0036. This study identifies new clinical and pathological markers for poor survival in PTLDs.


Asunto(s)
Trastornos Linfoproliferativos/diagnóstico , Trastornos Linfoproliferativos/mortalidad , Trasplante de Órganos/efectos adversos , Biomarcadores/análisis , Trastornos Linfoproliferativos/etiología , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Proteínas Proto-Oncogénicas c-bcl-6/análisis , Proteínas Proto-Oncogénicas c-myc/análisis , Factores de Riesgo , Análisis de Supervivencia , Proteína p53 Supresora de Tumor/análisis
3.
Metabolism ; 56(9): 1256-64, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17697870

RESUMEN

Indices of renal injury and oxidative stress were examined in mice with deficiency of cytosolic Cu(2+)/Zn(2+) superoxide dismutase (SOD1-/-, KO) and their wild-type (WT) littermates with streptozotocin-induced diabetes. After 5 weeks of diabetes, KO diabetic (D) but not WT-D mice developed marked albuminuria, increases in glomerular content of transforming growth factor beta, collagen alpha1(IV), and nitrotyrosine, and higher glomerular superoxide compared with corresponding values in nondiabetics. After 5 months of diabetes, increases in these parameters, mesangial matrix expansion, renal cortical malondialdehyde content, and severity of tubulointerstitial injury were all significantly greater, whereas cortical glutathione was lower, in KO-D than in WT-D. In contrast to WT-D, after 4 weeks of diabetes, KO-D mice did not develop the increase in inulin clearance (C(In)) characteristic of early diabetes. The nitric oxide synthase inhibitor N(omega)-nitro-l-arginine methylester suppressed C(In) in WT-D, but had no effect on C(In) in KO-D. Treatment of KO-D with the SOD mimetic tempol for 4 weeks suppressed albuminuria, increases in glomerular transforming growth factor beta, collagen alpha1(IV), nitrotyrosine, and glomerular superoxide, and concurrently increased C(In). The latter action of tempol in KO-D was blocked by the N(omega)-nitro-l-arginine methylester. The findings provide support for a role for superoxide and its metabolism by SOD1 in the pathogenesis of renal injury in diabetes in vivo, and implicate increased interaction of superoxide with nitric oxide as a pathogenetic factor.


Asunto(s)
Óxidos N-Cíclicos/farmacología , Óxidos N-Cíclicos/uso terapéutico , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/patología , Superóxido Dismutasa/genética , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Nefropatías Diabéticas/genética , Progresión de la Enfermedad , Hemoglobina Glucada/análisis , Inulina/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Óxido Nítrico/fisiología , Marcadores de Spin , Estreptozocina , Superóxido Dismutasa-1 , Factores de Tiempo
4.
Arch Pathol Lab Med ; 131(5): 799-804, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17488170

RESUMEN

Human parvovirus B19 is a single-stranded DNA virus with a predilection for infecting rapidly dividing cell lines, such as bone marrow erythroid progenitor cells. People with defective cell-mediated immunity (eg, severe combined immunodeficiency syndrome; acquired immunodeficiency syndrome; and patients receiving immunosuppressive therapy, ie, post organ transplant) can develop pure red cell aplasia, in which suppression of erythroid precursors is permanent. Identification of parvovirus inclusions in marrow biopsies and subsequent confirmation of infection by in situ hybridization is important in the assessment of anemia in immunodeficient patients. Our objective is to provide a general overview of the parvovirus B19 infection and its characteristics in immunocompromised patients and to summarize updated information regarding the clinicopathologic features, pathobiology, and laboratory diagnosis of this subject. The pathologist should be aware of the wide spectrum of manifestations of parvovirus B19 infection depending on the patient's hematologic and immunologic status.


Asunto(s)
Huésped Inmunocomprometido , Infecciones por Parvoviridae/inmunología , Humanos , Parvovirus B19 Humano
5.
Transpl Int ; 20(3): 277-90, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17291221

RESUMEN

We developed methods for prolonged (12 h), sterile, normothermic perfusion of rat kidneys and screened compounds for renal preservation including: mitochondrial transition pore inhibitor (decylubiquinone); caspase inhibitor (Z-VAD); peroxisome proliferator-activated receptor-alpha (PPARalpha) agonists (gemfibrozil, WY-14643); antioxidants (trolox, luteolin, quercetin); growth factors (HGF, PDGF, EGF, IGF-1, VEGF, transferrin); calpain inhibitor (Z-Val-Phe-CHO); calmodulin inhibitor (W7); K(ATP) opener (minoxidil, minoxidil sulfate); PARP inhibitor (3-aminobenzamide); calcium channel blocker (verapamil); V(2) agonist (DDAVP); diuretics (acetazolamide, hydrochlorothiazide, furosemide, mannitol); peroxisome proliferator-activated receptor-beta agonist (L-165041); dopamine agonist (dopamine); essential fatty acid (linolenic acid); beta-NAD; urea; uric acid; and aldosterone. In pilot studies, only PPARalpha agonists and mannitol provided promising results. Accordingly, these agents were investigated further. Fifteen rat kidneys were perfused for 12 h with L-15 media at 37 degrees C in the absence or presence of mannitol, gemfibrozil, gemfibrozil + mannitol or WY-14643. Chronic perfusion in untreated kidneys caused destruction of glomerular and tubular architecture (light and electron microscopy), disappearance of Na(+)-K(+)-ATPase-alpha(1) (Western blotting), and apoptosis (Apoptag staining). Gemfibrozil and WY-14643 marginally improved some biomarkers of renal preservation. However, the combination of gemfibrozil with mannitol markedly improved all parameters of renal preservation. We conclude that PPARalpha agonists, particularly when combined with mannitol, protect organs from normothermic, perfusion-induced damage.


Asunto(s)
Gemfibrozilo/farmacología , Riñón/fisiología , Manitol/farmacología , Preservación de Órganos/métodos , PPAR alfa/agonistas , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Interacciones Farmacológicas , Técnicas In Vitro , Riñón/efectos de los fármacos , Riñón/patología , Riñón/ultraestructura , Masculino , Microscopía Electrónica , Perfusión , Ratas , Ratas Sprague-Dawley , ATPasa Intercambiadora de Sodio-Potasio/análisis
6.
Prostate ; 66(12): 1311-8, 2006 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16705739

RESUMEN

BACKGROUND: Monocyte chemotactic protein-1 (MCP-1) plays a key role in the recruitment and activation of monocytes during inflammation. Increased MCP-1 serum levels in patients with various cancers were correlated with advanced stage. Here, we evaluated the role of MCP-1 on prostate cancer (CaP) cell proliferation and invasion. METHODS: Expression of MCP-1 in tissue specimens was analyzed by immunohistochemical staining. MCP-1 production was determined by ELISA in conditioned media collected from primary prostate epithelia (PrEC), LNCaP, C4-2B, PC3 cells, and hFOB. Cell proliferation and invasion were assayed by MTS assay and invasion chambers. RESULTS: All CaP cells, as well as hFOB, produced high amount of MCP-1 compared to PrEC cells. MCP-1 expression levels were associated with advanced pathologic stage. MCP-1 induced proliferation and invasion of CaP cells and this was abolished partially either by CCR2 antagonist or PI3 Kinase inhibitor. CONCLUSION: MCP-1 acts as a paracrine and autocrine factor for CaP growth and invasion.


Asunto(s)
Proliferación Celular , Quimiocina CCL2/fisiología , Invasividad Neoplásica/fisiopatología , Neoplasias de la Próstata/fisiopatología , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Quimiocina CCL2/metabolismo , Cromonas/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Masculino , Morfolinas/farmacología , Invasividad Neoplásica/patología , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Neoplasias de la Próstata/metabolismo , Receptores CCR2 , Receptores de Quimiocina/genética , Receptores de Quimiocina/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
7.
J Cardiovasc Pharmacol ; 46(4): 430-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16160593

RESUMEN

Pulmonary arterial hypertension (PH) is a deadly disease characterized by pulmonary arterial vasoconstriction and hypertension, pulmonary vasculature remodeling, and right ventricular hypertrophy. Our previous in vivo studies, performed in several models of cardiac, vascular, and/or renal injury, suggest that the metabolites of 17beta-estradiol may inhibit vascular and cardiac remodeling. The goal of this study was to determine whether 2-methoxyestradiol (2ME), major non-estrogenic estradiol metabolite, prevents the development and/or retards the progression of monocrotaline (MCT)-induced PH. First, a total of 27 male Sprague Dawley rats were injected with distillated water (Cont, n=6) or monocrotaline (MCT; 60 mg/kg, i.p.; n=21). Subsets of MCT animals (n=7 per group) received 2ME or its metabolic precursor 2-hydroxyestradiol (2HE; 10 microg/kg/h via osmotic minipumps) for 21 days. Next, an additional set (n=24) of control and MCT rats was monitored for 28 days, before right ventricular peak systolic pressure (RVPSP) was measured. Some pulmonary hypertensive animals (n=8) were treated with 2ME (10 microg/kg/h) beginning from day 14 after MCT administration. MCT caused pulmonary hypertension (ie, increased right ventricle/left ventricle+septum [RV/LV+S] ratio and wall thickness of small-sized pulmonary arteries, and elevated RVPSP) and produced high and late (days 22 to 27) mortality. Pulmonary hypertension was associated with strong proliferative response (PCNA staining) and marked inflammation (ED1+cells) in lungs. Both metabolites significantly attenuated the RV/LV+S ratio and pulmonary arteries media hypertrophy and reduced proliferative and inflammatory responses in the lungs. Furthermore, in diseased animals, 2ME (given from day 14 to 28) significantly decreased RVPSP, RV/LV+S ratio and wall thickness, and reduced mortality by 80% (mortality rate: 62.5% vs. 12.5%, MCT vs. MCT+2ME day 14 to 28). This study provides the first evidence that 2ME, a major non-estrogenic, non-carcinogenic metabolite of estradiol, prevents the development and retards the progression of monocrotaline-induced pulmonary hypertension. Further evaluation of 2ME for management of pulmonary arterial hypertension is warranted.


Asunto(s)
Estradiol/análogos & derivados , Hipertensión Pulmonar/prevención & control , 2-Metoxiestradiol , Animales , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Progresión de la Enfermedad , Estradiol/farmacología , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/fisiopatología , Hipertrofia Ventricular Derecha/inducido químicamente , Hipertrofia Ventricular Derecha/patología , Hipertrofia Ventricular Derecha/prevención & control , Inmunohistoquímica , Pulmón/química , Pulmón/efectos de los fármacos , Pulmón/fisiopatología , Masculino , Monocrotalina , Antígeno Nuclear de Célula en Proliferación/análisis , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Moduladores de Tubulina/farmacología
8.
J Cardiovasc Pharmacol ; 46(1): 25-35, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15965351

RESUMEN

Our previous studies in rodent models of nephropathy demonstrate that 2-hydroxyestradiol (2HE), an estradiol metabolite with little estrogenic activity, exerts renoprotective effects. In vivo, 2HE is readily converted to 2-methoxyestradiol (2ME), a major estradiol metabolite with no estrogenic activity. The goal of this study was to determine whether 2ME has renal and cardiovascular protective effects in vivo. First, the acute (90 minutes) and chronic (14 days) effects of 2ME (10 microg/kg/h) on blood pressure and renal function were examined in normotensive and spontaneously hypertensive rats (SHR). Second, a rat model of cardiovascular and renal injury induced by chronic nitric oxide synthase inhibition (N-nitro-L-arginine; 40 mg/kg/d; LNNA group) was used to examine the protective effects of estradiol metabolites. Subsets of LNNA-treated rats were administered either 2HE or 2ME (10 microg/kg/h via osmotic minipump; LNNA+2ME and LNNA+2HE groups, respectively. 2-Methoxyestradiol had no acute or chronic effects on blood pressure or renal function in normotensive animals or on hypertension in SHR. Prolonged, 5-week NOS inhibition induced severe cardiovascular and renal disease and high mortality (75%, LNNA group). 2ME, but not 2HE, significantly decreased elevated blood pressure and attenuated the reduction in GFR. 2HE delayed the onset of proteinuria, whereas no proteinuria was detected in the 2-ME group. 2HE and 2ME reduced mortality rate by 66% and 83%, respectively (P < 0.001). In the kidney, 2HE and 2ME abolished LNNA-induced interstitial and glomerular inflammation, attenuated glomerular collagen IV synthesis, and inhibited glomerular and tubular cell proliferation. In the heart, 2HE and 2ME markedly reduced vascular and interstitial inflammation and reduced collagen synthesis and vascular/interstitial cell proliferation. This study provides the first evidence that, in a model of severe cardiovascular and renal injury, 2-methoxyestradiol (a major nonestrogenic estradiol metabolite) exerts renal and cardiovascular protective effects and reduces mortality.


Asunto(s)
Enfermedades Cardiovasculares/tratamiento farmacológico , Estradiol/análogos & derivados , Enfermedades Renales/tratamiento farmacológico , Óxido Nítrico Sintasa/antagonistas & inhibidores , 2-Metoxiestradiol , Animales , Células Presentadoras de Antígenos/efectos de los fármacos , Células Presentadoras de Antígenos/inmunología , Peso Corporal/efectos de los fármacos , Enfermedades Cardiovasculares/inducido químicamente , Creatinina/sangre , Inhibidores Enzimáticos/farmacología , Estradiol/administración & dosificación , Estradiol/metabolismo , Estradiol/uso terapéutico , Tasa de Filtración Glomerular/efectos de los fármacos , Corazón/efectos de los fármacos , Corazón/fisiopatología , Infusiones Intravenosas , Enfermedades Renales/inducido químicamente , Masculino , Nitroarginina/farmacología , Proteinuria/sangre , Ratas , Ratas Endogámicas SHR , Ratas Sprague-Dawley , Circulación Renal/efectos de los fármacos , Factores de Tiempo
9.
Blood ; 105(9): 3722-30, 2005 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-15650054

RESUMEN

Mantle-cell lymphoma (MCL) is a unique subtype of B-cell non-Hodgkin lymphoma (NHL) that behaves aggressively and remains incurable. In order to understand the pathogenesis of MCL and design new therapies, it is important to accurately analyze molecular changes in pathways dysregulated in MCL. We used antibody microarrays to compare patterns of protein expression between CD19(+) purified B lymphocytes from normal tonsil and 7 cases of histologically confirmed MCL. Protein overexpression was defined as a higher than 1.3-fold or 2-fold increase in at least 67% of tumor samples compared with normal B-cell control. Of the polypeptides, 77 were overexpressed using the higher than 1.3-fold cutoff, and 13 were overexpressed using the 2-fold cutoff. These included cell cycle regulators (regulator of chromosome condensation 1 [RCC1], murine double minute 2 [MDM2]), a kinase (citron Rho-interacting kinase [CRIK]), chaperone proteins (heat shock 90-kDa protein [Hsp90], Hsp10), and phosphatase regulators (A-kinase anchor protein 1 [AKAP149], protein phosphatase 5 [PP5], and inhibitor 2). The elevated expression of some of these polypeptides was confirmed by immunoblotting and immunohistochemistry, whereas elevated expression of others could not be confirmed, illustrating the importance of confirmatory studies. This study describes a novel technique that identifies proteins dysregulated in MCL.


Asunto(s)
Linfoma de Células del Manto/química , Proteínas de Neoplasias/análisis , Proteómica/métodos , Anciano , Anciano de 80 o más Años , Linfocitos B , Biopsia , Análisis por Conglomerados , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ganglios Linfáticos/patología , Linfoma de Células del Manto/patología , Masculino , Persona de Mediana Edad , Análisis por Matrices de Proteínas
10.
Carcinogenesis ; 26(2): 303-8, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15564291

RESUMEN

Lung cancer mortality rates in the Xuan Wei County population are among the highest in China and are associated with exposure to indoor emissions from the burning of smoky coal. Previous studies of lung tumors from both non-smoking women and smoking men in this region showed high frequencies of mutations, consisting mostly of G-->T transversions in the p53 tumor suppressor gene and K-ras oncogene, suggesting that these mutations were caused primarily by polycyclic aromatic hydrocarbons. In this study sputum samples from 92 individuals with no evidence of lung cancer from Xuan Wei County were screened for p53 and K-ras mutations. Sputum cells were collected on glass slides by sputum cytocentrifugation, stained and cytopathologically analyzed. Cytologically non-malignant epithelial cells were taken from each sputum sample using a laser capture microdissection microscope and molecularly analyzed. Cells taken from the sputum of 15 (16.3%) individuals were mutation positive, including 13 (14.1%) individuals each with a p53 mutation, 1 (1.1%) individual with a K-ras mutation and 1 (1.1%) individual with a p53 and a K-ras mutation. p53 mutations were found in both the sputum of individuals with evidence of chronic bronchitis (3 of 46 or 6.5%) and those without evidence of this disease (11 of 46 or 23.9%). Therefore, mutations in the p53 gene and, to a lesser extent, the K-ras gene were frequent in non-malignant epithelial cells taken from the sputum of individuals without evidence of lung cancer who were exposed to smoky coal emissions in Xuan Wei County and were at a high risk for developing the disease.


Asunto(s)
Contaminación del Aire Interior/efectos adversos , Genes p53/genética , Genes ras/genética , Neoplasias Pulmonares/genética , Esputo/citología , Bronquitis Crónica/genética , Bronquitis Crónica/patología , China , Carbón Mineral/efectos adversos , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Microdisección , Mutación/genética
11.
Cancer Lett ; 212(1): 121-30, 2004 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-15246568

RESUMEN

Mutations in the p53 tumor suppressor gene are frequent in breast tumors but the implication of p53 mutations in breast cancer development remains poorly understood. In this study, we applied laser capture microdissection (LCM) microscope to histologically review and sample cells from paraffin-embedded breast tissue sections obtained from six cases of ductal carcinoma in situ (DCIS) and ten cases of atypical ductal hyperplasia (ADH). p53 mutations were detected, using single stranded conformational polymorphism (SSCP) and sequencing, in cell samples of three cases with DCIS and five cases with ADH. p53 mutations are therefore present in DCIS and ADH of the breast, considered as pre-malignant precursors to breast cancer, and some of them may represent early events in breast cancer development.


Asunto(s)
Neoplasias de la Mama/genética , Mama/patología , Carcinoma Intraductal no Infiltrante/genética , Análisis Mutacional de ADN , Genes p53 , Neoplasias de la Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Transformación Celular Neoplásica , Femenino , Humanos , Hiperplasia , Microdisección , Adhesión en Parafina , Polimorfismo Conformacional Retorcido-Simple , Lesiones Precancerosas
12.
Diabetes ; 53(3): 762-8, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14988262

RESUMEN

The effects of overexpression of Cu(2+)/Zn(2+) superoxide dismutase-1 (SOD-1) on indexes of renal injury were compared in 5-month-old nontransgenic (NTg) db/db mice and db/db mice hemizygous for the human SOD-1 transgene (SOD-Tg). Both diabetic groups exhibited similar hyperglycemia and weight gain. However, in NTg-db/db mice, albuminuria, glomerular accumulation of immunoreactive transforming growth factor-beta, collagen alpha1(IV), nitrotyrosine, and mesangial matrix were all significantly increased compared with either nondiabetic mice or SOD-Tg-db/db. SOD-1 activity and reduced glutathione levels were higher, whereas malondialdehyde content was lower, in the renal cortex of SOD-Tg-db/db compared with NTg-db/db mice, consistent with a renal antioxidant effect in the transgenic mice. Inulin clearance (C(IN)) and urinary excretion of guanosine 3',5'-cyclic monophosphate (U(cGMP)) were increased in SOD-Tg-db/db mice compared with corresponding values in nondiabetic mice or NTg-db/db mice. C(IN) and U(cGMP) were suppressed by Nomega-nitro-L-arginine methyl ester in SOD-Tg-db/db but not in NTg-db/db mice, implying nitric oxide (NO) dependence of these increases and enhanced renal NO bioactivity in SOD-Tg-db/db. Studies of NO-responsive cGMP in isolated glomeruli supported greater quenching of NO in glomeruli from NTg-db/db compared with SOD-Tg-db/db mice. Evidence of increased NO responsiveness and the suppression of glomerular nitrotyrosine may both reflect reduced NO-superoxide interaction in SOD-Tg-db/db mice. The results implicate superoxide in the pathogenesis of diabetic nephropathy.


Asunto(s)
Nefropatías Diabéticas/prevención & control , Riñón/patología , Óxido Nítrico/fisiología , Superóxido Dismutasa/metabolismo , Superóxidos/metabolismo , Animales , Secuencia de Bases , GMP Cíclico/metabolismo , Cartilla de ADN , Nefropatías Diabéticas/enzimología , Nefropatías Diabéticas/patología , Humanos , Inmunohistoquímica , Inulina/orina , Glomérulos Renales/enzimología , Glomérulos Renales/patología , Ratones , Ratones Transgénicos , NG-Nitroarginina Metil Éster/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Superóxido Dismutasa/genética , Superóxido Dismutasa-1 , Factor de Crecimiento Transformador beta/metabolismo
13.
Inflamm Bowel Dis ; 9(4): 230-6, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12902846

RESUMEN

Nonsteroidal anti-inflammatory drugs decrease sporadic colorectal carcinoma and adenomas in patients with familial adenomatous polyposis and in rodent models of sporadic colon cancer and familial adenomatous polyposis. Similarly, selective cyclooxygenase 2 inhibitors decrease adenomas in humans and rodents. However, their effects on chronic colitis and colitis-associated neoplasia are unknown. Interleukin 10-/- mice (C57/B6) were fed regular chow (n = 20) or chow with celecoxib (1,500 ppm, n = 18) or rofecoxib (75 ppm, n = 20) for 12 weeks. Twenty-eight percent of the celecoxib group died versus 5% of the control and rofecoxib groups (p < 0.05 compared with control). Celecoxib and rofecoxib increased the incidence of colitis (26% vs. 92% and 68%, p < 0.01), colitis score (0.4 +/- 0.2 vs. 2.5 +/- 0.3 and 2 +/- 0.4, p < 0.01), aberrant crypt foci (0.5 +/- 0.3 vs. 3.7 +/- 2.6 and 2.8 +/- 0.7, p < 0.01), aberrant crypts per mouse (4.11 +/- 2.1 vs. 41.2 +/- 9.7 and 27.1 +/- 7.5, p < 0.01) and dysplasia (11% vs. 54% and 42%, p < 0.01). Similarly, indomethacin (9 ppm, n = 15) increased colitis score, aberrant crypt foci, and dysplasia after 27 days of treatment. Two selective cyclooxygenase 2 inhibitors exacerbate colitis and premalignant changes in the interleukin 10-/- mouse model of chronic colitis and colitis-associated colon carcinoma.


Asunto(s)
Colitis/inducido químicamente , Inhibidores de la Ciclooxigenasa/toxicidad , Interleucina-10/farmacología , Lactonas/toxicidad , Lesiones Precancerosas/inducido químicamente , Sulfonamidas/toxicidad , Animales , Celecoxib , Colitis/patología , Neoplasias Colorrectales/inducido químicamente , Neoplasias Colorrectales/patología , Modelos Animales de Enfermedad , Inmunohistoquímica , Ratones , Ratones Noqueados , Lesiones Precancerosas/patología , Pirazoles , Sulfonas
14.
Carcinogenesis ; 24(10): 1671-6, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12844488

RESUMEN

Lung cancer, a disease related mostly to tobacco smoke exposure and a leading cause of cancer-related death in industrialized countries, is frequently associated with mutations in the p53 tumor suppressor gene. Genetic differences resulting in inter-individual variation in DNA repair capacity may in part account for susceptibility of a cell to genotoxic agents leading to somatic mutations, including p53 mutations, and eventual transformation of a normal cell into a malignant phenotype. The objective of this study is to investigate the relationship between the polymorphisms of two DNA repair genes, the nucleotide excision repair xeroderma pigmentosum group D (XPD) gene (codons 312 and 751) and the base excision repair X-ray repair cross-complementing group 1 (XRCC1) gene (codon 399), and p53 mutations among lung cancer patients. Lung tumors from 204 smokers with non-small cell lung cancer (NSCLC) were analyzed for mutations in exons 5-8 of the p53 gene and genotypes of XPD and XRCC1. p53 mutations were found in 20% (40/204) of the patients. Patients with the XPD codon 312 Asn allele were less likely to have p53 mutations (13.8%) than XPD 312 Asp/Asp (27.3%) [odds ratio (OR) 0.43, 95% confidence interval (CI) 0.20-0.89, P = 0.023]. No association was found between p53 mutations and either XPD Lys751Gln or XRCC1 Arg399Gln. However, the p53 mutation frequency increased with the increased number of the combined genotypes among XPD 312WT (Asp/Asp), XPD 751VT (Lys/Gln or Gln/Gln) or XRCC1 399VT (Arg/Gln or Gln/Gln) (P = 0.01, trend test). These results suggest that individuals who smoke and have the XPD codon 312 Asp/Asp genotype may be at a greater risk of p53 mutations, especially if combined with other polymorphisms that may result in deficient DNA repair.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , ADN Helicasas , Genes p53 , Neoplasias Pulmonares/genética , Proteínas/genética , Fumar/efectos adversos , Factores de Transcripción , Alelos , Carcinoma de Pulmón de Células no Pequeñas/etiología , Análisis Mutacional de ADN , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Femenino , Genotipo , Humanos , Neoplasias Pulmonares/etiología , Masculino , Mutación , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X , Proteína de la Xerodermia Pigmentosa del Grupo D
15.
Lung Cancer ; 40(2): 141-50, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12711114

RESUMEN

The p53 gene is frequently mutated in lung tumors, and mutations may be caused by both polycyclic aromatic hydrocarbons (PAHs) and nitrosamines found in tobacco smoke. The two major forms of lung cancer, adenocarcinoma (AC) and squamous cell carcinoma (SCC), are known to differ in the proportion of tumors exhibiting p53 mutation, and may also differ in the mutational spectra produced. Previous studies comparing p53 mutational spectra between AC and SCC of the lung have been limited by small sample size. We examined p53 mutations in exons 5-8 in 202 cases of AC and 82 cases of SCC from smoking lung cancer patients in the Western Pennsylvania region. The percent of cases with p53 mutation was significantly lower in ACs (40/202, 20%) compared to SCCs (29/82, 35%, P=0.006). The proportion of mutations present that were G to T transversions was not significantly different between the two tumor types (52% of p53 mutations in AC compared to 32% in SCC). G to A transitions either did not differ in frequency in the two types of lung cancer (20% of mutations in AC and 24% of mutations in SCC). A distinct spectrum was observed, however, in the p53 mutation pattern in the two types of lung cancer. ACs showed a strong preference for a mutational hotspot at codons 248 and 249, while squamous cell tumors showed mutational events spread throughout exons 5-8, with a preference for codon 267. Mutations at codon 267 in SCC were all C to T transitions that occurred at CpG sites. Both tumor types demonstrated preferential mutation of the non-transcribed strand (100% of all G to T transversions and 55% of the G to A transitions). These results suggest that p53 mutations in both types of lung tumors may arise from adduction by both PAHs and nitrosamines. Mutations arising in ACs appear selectively in regions of p53 that produce more rigid proteins, suggesting a drastic change in p53 function is needed to result in ACs, while less constrained changes in p53 function can result in SCCs. Mutation in p53 was not found to be related to patient survival in this group of patients, while tumor size and degree of differentiation were poor survival predictors.


Asunto(s)
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , ADN de Neoplasias/genética , Genes p53 , Neoplasias Pulmonares/genética , Mutación , Anciano , Codón/genética , Análisis Mutacional de ADN , Cartilla de ADN/química , Exones/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Tasa de Supervivencia
16.
Appl Immunohistochem Mol Morphol ; 10(3): 225-30, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12373148

RESUMEN

E2F-4 is a transcription factor involved in the transition of the cell from the resting state (G0/G1) to the proliferative stage (S). It has been associated with the p107 and p130 members of the Rb-family and it is responsible for many important growth suppressive functions. E2F-1, one member of the E2F family, has a similar structure to E2F-4; however, both have different mechanisms of action in regulating cell-cycle progression. Although E2F-4 acts mainly as a repressor in the early part of the cell cycle, E2F-1 has the ability to function as both an oncogene and a tumor suppressor gene. In an attempt to identify the role of E2F-4 as a potential mediator of cell proliferation, differentiation, tumorigenesis, and apoptosis in colorectal mucosa comparing with that of E2F-1, the authors examine 20 patients with human colon cancer and their corresponding histologically healthy mucosa by using immunohistochemical methods, computerized quantitative image analysis, and immunoblot analysis. Immunohistochemical studies were performed with formalin-fixed, paraffin-embedded sections stained with a monoclonal antibody against the E2F-4 protein. Apoptosis levels were determined by in situ assay. Positivity was scored by a Computerized Image Analyzer to detect the relative amount of the protein. Immunoblot analysis was performed on protein extracts from snap-frozen tissues of the same specimens. The results show that the expression of E2F-4 was greater in the tumor cells than in their corresponding benign epithelium as determined by immunohistochemical staining and image analysis. This was confirmed by semiquantitative IB analysis of the E2F-4 protein. The labeling index (LI) of E2F-4 in the tumors was inversely proportional to the LI of apoptotic cells. Within these cases, 12 cases showed a very high E2F-4 LI corresponding to low apoptosis LI. Three cases with relatively lower levels of E2F-4 LI were characterized with high apoptotic rates. These data suggest that E2F-4 gene overexpression plays a role in the development of colorectal tumors and appears to play a role in suppressing apoptosis.


Asunto(s)
Adenocarcinoma/genética , Neoplasias Colorrectales/genética , Proteínas de Unión al ADN/genética , Inmunohistoquímica/métodos , Factores de Transcripción/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Apoptosis/genética , Apoptosis/fisiología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Proteínas de Unión al ADN/metabolismo , Factor de Transcripción E2F4 , Expresión Génica , Genes Supresores de Tumor , Humanos , Procesamiento de Imagen Asistido por Computador , Immunoblotting/métodos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Factores de Transcripción/metabolismo
17.
Clin Exp Metastasis ; 19(4): 351-8, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12090476

RESUMEN

The FHIT gene, a member of the histidine triad family has been identified as a tumor suppressor gene. Molecular genetic approaches to determine alterations in the FHIT gene in colorectal cancers have produced varying results with reported abnormalities of the FHIT gene transcripts in 13% to 50% of cases studied. FHIT has been reported to be involved in the regulation of apoptosis and cell cycle in cell culture systems. Immunohistochemical (IHC) studies of FHIT expression in human colon cancer and its correlation to apoptosis and clinical prognosis have been sparse. We studied 100 human colorectal cancers by IHC and a computerized image analysis (CIA) method to evaluate FHIT expression and the rate of apoptosis in tumors and corresponding mucosae. Follow-up data for at least five years was available for all patients. We correlated the results with tumor grade, stage and clinical prognosis. We used commercially available polyclonal anti FHIT antibody and Apoptaq kit on paraffin-embedded tumors and their corresponding mucosae and the SAMBA 4000 CIA system to evaluate the labeling index (LI), the mean optical density (MOD) of the stain and calculate a quick score (QS). The LI is the ratio of positively stained areas to the total area of the tissues examined, the MOD represents the concentration of the positive stain as measured per positive pixels and the QS a numeric product of the LI and MOD for each microscopic area examined. Image analysis of IHC staining of the tumor sections defined three main groups based on the reactivity of the anti FHIT polyclonal antibody. Group I included 23 cases where the LI was less than 55% with a mean of 36%. Eight cases in this group showed complete loss of FHIT expression. Group II included 41 cases where the LI was between 55% and 65% with a mean of 60%. Group III was composed of 36 cases where the LI was more than 65% with a mean of 69%. Our data showed that the absence or reduction of FHIT protein in the tumors, relative to morphologically normal mucosa, plays a role in the development of a few colorectal cancers (23%). Poorly differentiated carcinomas showed absent or decreased FHIT. A reduction of FHIT was positively correlated with the rate of distant metastases and worse prognosis. Over-expression of FHIT is directly proportional to the apoptotic rate in the tumors examined. CIA provides an objective and accurate assessment of the staining patterns and generates numerical data evaluating intensity better than depending on subjective light microscopy alone.


Asunto(s)
Ácido Anhídrido Hidrolasas , Adenocarcinoma/metabolismo , Apoptosis , Neoplasias Colorrectales/metabolismo , Metástasis de la Neoplasia , Proteínas de Neoplasias/fisiología , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Diferenciación Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Células Epiteliales/química , Células Epiteliales/ultraestructura , Estudios de Seguimiento , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Mucosa Intestinal/química , Proteínas de Neoplasias/deficiencia , Proteínas de Neoplasias/genética , Estadificación de Neoplasias , Adhesión en Parafina , Pronóstico , Estudios Retrospectivos , Manejo de Especímenes , Coloración y Etiquetado , Análisis de Supervivencia
18.
Int J Colorectal Dis ; 17(4): 280-3, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12073078

RESUMEN

BACKGROUND: Pure, benign epidermoid cysts of the abdominal viscera are rare. There have been only four reports of epidermoid cysts of the cecum in the literature, two following appendectomies and attributed to the surgical procedure, and two in female patients, raising the possibility of dermoid cysts related to the ovaries. PATIENTS AND METHODS: We report the first case of epidermoid cyst of the cecum in an elderly man with no previous history of trauma or surgery, detected by computed tomography as an incidental finding of extraluminal cystic cecal mass. It was treated by partial colectomy. Pathologically the cyst was roughly spherical, extending from and expanding the serosal surface of the cecum with no communication through the muscularis wall. Histologically the inner lining of the cyst was composed of benign, mature, keratinized, stratified squamous epithelium with a well formed granular layer. No calcification, hair, teeth, or bone elements was detected. RESULTS: The interesting finding in our case is the unusual anatomical location and the age and sex of the patient. The patient had no history of any abdominal surgical procedures. The most likely explanation for the presence and development of an epidermoid cyst in this location is the result of an aberrant ectodermal implantation during embryogenesis. CONCLUSION: Awareness of the possibility of the presence of epidermoid cysts in this area with distinctive radiological findings consistent with a well circumscribed benign cyst should be considered in the differential diagnosis of cysts within the abdomen.


Asunto(s)
Enfermedades del Ciego/epidemiología , Quiste Epidérmico/epidemiología , Anciano , Enfermedades del Ciego/diagnóstico por imagen , Enfermedades del Ciego/cirugía , Ciego/patología , Colectomía , Quiste Epidérmico/diagnóstico por imagen , Quiste Epidérmico/cirugía , Femenino , Humanos , Masculino , Tomografía Computarizada por Rayos X
19.
J Am Soc Nephrol ; 13(1): 108-116, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11752027

RESUMEN

Previous studies demonstrated that 2 mo of dietary supplementation with alpha-lipoic acid (LA) prevented early glomerular injury in non-insulin-treated streptozotocin diabetic rats (D). The present study examined the effects of chronic LA supplementation (30 mg/kg body wt per d) on nephropathy in D after 7 mo of diabetes. Compared with control rats, D developed increased urinary excretion of albumin and transforming growth factor beta, renal insufficiency, glomerular mesangial matrix expansion, and glomerulosclerosis in association with depletion of glutathione and accumulation of malondialdehyde in renal cortex. LA prevented or ameliorated all of these changes in D. Because chronic LA supplementation also attenuated hyperglycemia in D after 3 mo, its effects on renal injury were compared with treatment of rats with sufficient insulin to maintain a level of glycemic control for the entire 7-mo period (D-INS) equivalent to that observed with LA during the final 4 mo. Despite superior longitudinal glycemic control in D-INS, urinary excretion of albumin and transforming growth factor beta, glomerular mesangial matrix expansion, the extent of glomerulosclerosis, and renal cortical malondialdehyde content were all significantly greater, whereas cortical glutathione content was lower than corresponding values in D given LA. Thus, the renoprotective effects of LA in D were not attributable to improved glycemic control alone but also likely reflected its antioxidant activity. The combined antioxidant and hypoglycemic actions of LA both may contribute to its utility in preventing renal injury and other complications of diabetes.


Asunto(s)
Antioxidantes/farmacología , Diabetes Mellitus Experimental/fisiopatología , Nefropatías Diabéticas/prevención & control , Mesangio Glomerular/efectos de los fármacos , Mesangio Glomerular/patología , Hiperglucemia/sangre , Hipoglucemiantes/farmacología , Ácido Tióctico/farmacología , Albuminuria/etiología , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/patología , Femenino , Glutatión/metabolismo , Corteza Renal/metabolismo , Malondialdehído/metabolismo , Ratas , Insuficiencia Renal/etiología , Insuficiencia Renal/prevención & control , Factor de Crecimiento Transformador beta/orina
20.
J Am Soc Nephrol ; 12(1): 124-133, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11134258

RESUMEN

Antioxidants, in particular vitamin E (VE), have been reported to protect against diabetic renal injury. alpha-Lipoic acid (LA) has been found to attenuate diabetic peripheral neuropathy, but its effects on nephropathy have not been examined. In the present study, parameters of glomerular injury were examined in streptozotocin diabetic rats after 2 mo on unsupplemented diets and in diabetic rats that received the lowest daily dose of dietary LA (30 mg/kg body wt), VE (100 IU/kg body wt), or vitamin C (VC; 1 g/kg body wt), which detectably increased the renal cortical content of each antioxidant. Blood glucose values did not differ among the diabetic groups. At 2 mo, inulin clearance, urinary albumin excretion, fractional albumin clearance, glomerular volume, and glomerular content of immunoreactive transforming growth factor-beta (TGF-beta) and collagen alpha1 (IV) all were significantly increased in unsupplemented D compared with age-matched nondiabetic controls. With the exception of inulin clearance, LA prevented or significantly attenuated the increase in all of these glomerular parameters in D, as well as the increases in renal tubular cell TGF-beta seen in D. At the dose used, VE reduced inulin clearance in D to control levels but failed to alter any of the other indices of glomerular injury or to suppress renal tubular cell TGF-beta in D. VC suppressed urinary albumin excretion, fractional albumin clearance, and glomerular volume but not glomerular or tubular TGF-beta or glomerular collagen alpha1 (IV) content. LA but not VE or VC significantly increased renal cortical glutathione content in D. These data indicate that LA is effective in the prevention of early diabetic glomerular injury and suggest that this agent may have advantages over high doses of either VE or VC.


Asunto(s)
Antioxidantes/administración & dosificación , Diabetes Mellitus Experimental/dietoterapia , Nefropatías Diabéticas/prevención & control , Suplementos Dietéticos , Glomérulos Renales/efectos de los fármacos , Ácido Tióctico/administración & dosificación , Animales , Colágeno/metabolismo , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/metabolismo , Femenino , Inmunohistoquímica , Glomérulos Renales/lesiones , Glomérulos Renales/metabolismo , Ratas , Ratas Sprague-Dawley , Factor de Crecimiento Transformador beta/metabolismo
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