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1.
Mol Carcinog ; 48(7): 633-41, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19072763

RESUMO

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.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Genes p53 , Neoplasias Pulmonares/genética , Pulmão/metabolismo , Mutação , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
Leuk Lymphoma ; 49(9): 1738-44, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18798108

RESUMO

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.


Assuntos
Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/mortalidade , Transplante de Órgãos/efeitos adversos , Biomarcadores/análise , Transtornos Linfoproliferativos/etiologia , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-6/análise , Proteínas Proto-Oncogênicas c-myc/análise , Fatores de Risco , Análise de Sobrevida , Proteína Supressora de Tumor p53/análise
3.
Transpl Int ; 20(3): 277-90, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17291221

RESUMO

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.


Assuntos
Genfibrozila/farmacologia , Rim/fisiologia , Manitol/farmacologia , Preservação de Órgãos/métodos , PPAR alfa/agonistas , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Interações Medicamentosas , Técnicas In Vitro , Rim/efeitos dos fármacos , Rim/patologia , Rim/ultraestrutura , Masculino , Microscopia Eletrônica , Perfusão , Ratos , Ratos Sprague-Dawley , ATPase Trocadora de Sódio-Potássio/análise
4.
Prostate ; 66(12): 1311-8, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16705739

RESUMO

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.


Assuntos
Proliferação de Células , Quimiocina CCL2/fisiologia , Invasividade Neoplásica/fisiopatologia , Neoplasias da Próstata/fisiopatologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimiocina CCL2/metabolismo , Cromonas/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Masculino , Morfolinas/farmacologia , Invasividade Neoplásica/patologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Neoplasias da Próstata/metabolismo , Receptores CCR2 , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
5.
J Cardiovasc Pharmacol ; 46(4): 430-7, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16160593

RESUMO

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.


Assuntos
Estradiol/análogos & derivados , Hipertensão Pulmonar/prevenção & controle , 2-Metoxiestradiol , Animais , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Progressão da Doença , Estradiol/farmacologia , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/induzido quimicamente , Hipertrofia Ventricular Direita/patologia , Hipertrofia Ventricular Direita/prevenção & controle , Imuno-Histoquímica , Pulmão/química , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Masculino , Monocrotalina , Antígeno Nuclear de Célula em Proliferação/análise , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Moduladores de Tubulina/farmacologia
6.
J Cardiovasc Pharmacol ; 46(1): 25-35, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15965351

RESUMO

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.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Estradiol/análogos & derivados , Nefropatias/tratamento farmacológico , Óxido Nítrico Sintase/antagonistas & inibidores , 2-Metoxiestradiol , Animais , Células Apresentadoras de Antígenos/efeitos dos fármacos , Células Apresentadoras de Antígenos/imunologia , Peso Corporal/efeitos dos fármacos , Doenças Cardiovasculares/induzido quimicamente , Creatinina/sangue , Inibidores Enzimáticos/farmacologia , Estradiol/administração & dosagem , Estradiol/metabolismo , Estradiol/uso terapêutico , Taxa de Filtração Glomerular/efeitos dos fármacos , Coração/efeitos dos fármacos , Coração/fisiopatologia , Infusões Intravenosas , Nefropatias/induzido quimicamente , Masculino , Nitroarginina/farmacologia , Proteinúria/sangue , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Circulação Renal/efeitos dos fármacos , Fatores de Tempo
7.
Blood ; 105(9): 3722-30, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15650054

RESUMO

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.


Assuntos
Linfoma de Célula do Manto/química , Proteínas de Neoplasias/análise , Proteômica/métodos , Idoso , Idoso de 80 Anos ou mais , Linfócitos B , Biópsia , Análise por Conglomerados , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Linfonodos/patologia , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Análise Serial de Proteínas
8.
Carcinogenesis ; 26(2): 303-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15564291

RESUMO

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.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Genes p53/genética , Genes ras/genética , Neoplasias Pulmonares/genética , Escarro/citologia , Bronquite Crônica/genética , Bronquite Crônica/patologia , China , Carvão Mineral/efeitos adversos , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Microdissecção , Mutação/genética
9.
Cancer Lett ; 212(1): 121-30, 2004 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-15246568

RESUMO

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.


Assuntos
Neoplasias da Mama/genética , Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Análise Mutacional de DNA , Genes p53 , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Transformação Celular Neoplásica , Feminino , Humanos , Hiperplasia , Microdissecção , Inclusão em Parafina , Polimorfismo Conformacional de Fita Simples , Lesões Pré-Cancerosas
10.
Inflamm Bowel Dis ; 9(4): 230-6, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12902846

RESUMO

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.


Assuntos
Colite/induzido quimicamente , Inibidores de Ciclo-Oxigenase/toxicidade , Interleucina-10/farmacologia , Lactonas/toxicidade , Lesões Pré-Cancerosas/induzido quimicamente , Sulfonamidas/toxicidade , Animais , Celecoxib , Colite/patologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Lesões Pré-Cancerosas/patologia , Pirazóis , Sulfonas
11.
Carcinogenesis ; 24(10): 1671-6, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12844488

RESUMO

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.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , DNA Helicases , Genes p53 , Neoplasias Pulmonares/genética , Proteínas/genética , Fumar/efeitos adversos , Fatores de Transcrição , Alelos , Carcinoma Pulmonar de Células não Pequenas/etiologia , Análise Mutacional de DNA , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Feminino , Genótipo , Humanos , Neoplasias Pulmonares/etiologia , Masculino , Mutação , Reação em Cadeia da Polimerase , Polimorfismo Genético , Proteína 1 Complementadora Cruzada de Reparo de Raio-X , Proteína Grupo D do Xeroderma Pigmentoso
12.
Lung Cancer ; 40(2): 141-50, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12711114

RESUMO

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.


Assuntos
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , DNA de Neoplasias/genética , Genes p53 , Neoplasias Pulmonares/genética , Mutação , Idoso , Códon/genética , Análise Mutacional de DNA , Primers do DNA/química , Éxons/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Taxa de Sobrevida
13.
Appl Immunohistochem Mol Morphol ; 10(3): 225-30, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12373148

RESUMO

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.


Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , Imuno-Histoquímica/métodos , Fatores de Transcrição/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose/genética , Apoptose/fisiologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Ligação a DNA/metabolismo , Fator de Transcrição E2F4 , Expressão Gênica , Genes Supressores de Tumor , Humanos , Processamento de Imagem Assistida por Computador , Immunoblotting/métodos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Fatores de Transcrição/metabolismo
14.
Clin Exp Metastasis ; 19(4): 351-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12090476

RESUMO

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.


Assuntos
Hidrolases Anidrido Ácido , Adenocarcinoma/metabolismo , Apoptose , Neoplasias Colorretais/metabolismo , Metástase Neoplásica , Proteínas de Neoplasias/fisiologia , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Diferenciação Celular , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Células Epiteliais/química , Células Epiteliais/ultraestrutura , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Mucosa Intestinal/química , Proteínas de Neoplasias/deficiência , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Inclusão em Parafina , Prognóstico , Estudos Retrospectivos , Manejo de Espécimes , Coloração e Rotulagem , Análise de Sobrevida
15.
Int J Colorectal Dis ; 17(4): 280-3, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12073078

RESUMO

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.


Assuntos
Doenças do Ceco/epidemiologia , Cisto Epidérmico/epidemiologia , Idoso , Doenças do Ceco/diagnóstico por imagem , Doenças do Ceco/cirurgia , Ceco/patologia , Colectomia , Cisto Epidérmico/diagnóstico por imagem , Cisto Epidérmico/cirurgia , Feminino , Humanos , Masculino , Tomografia Computadorizada por Raios X
16.
J Am Soc Nephrol ; 13(1): 108-116, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11752027

RESUMO

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.


Assuntos
Antioxidantes/farmacologia , Diabetes Mellitus Experimental/fisiopatologia , Nefropatias Diabéticas/prevenção & controle , Mesângio Glomerular/efeitos dos fármacos , Mesângio Glomerular/patologia , Hiperglicemia/sangue , Hipoglicemiantes/farmacologia , Ácido Tióctico/farmacologia , Albuminúria/etiologia , Animais , Glicemia/análise , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Feminino , Glutationa/metabolismo , Córtex Renal/metabolismo , Malondialdeído/metabolismo , Ratos , Insuficiência Renal/etiologia , Insuficiência Renal/prevenção & controle , Fator de Crescimento Transformador beta/urina
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