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2.
Oncogene ; 36(15): 2172-2183, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27819678

RESUMO

Genetic alterations associated with prostate cancer (PCa) may be identified by sequencing metastatic tumour genomes to identify molecular markers at this lethal stage of disease. Previously, we characterized somatic alterations in metastatic tumours in the methylcytosine dioxygenase ten-eleven translocation 2 (TET2), which is altered in 5-15% of myeloid, kidney, colon and PCas. Genome-wide association studies previously identified non-coding risk variants associated with PCa and melanoma. We perform fine-mapping of PCa risk across TET2 using genotypes from the PEGASUS case-control cohort and identify six new risk variants in introns 1 and 2. Oligonucleotides containing two risk variants are bound by the transcription factor octamer-binding protein 1 (Oct1/POU2F1) and TET2 and Oct1 expression are positively correlated in prostate tumours. TET2 is expressed in normal prostate tissue and reduced in a subset of tumours from the Cancer Genome Atlas (TCGA). Small interfering RNA-mediated TET2 knockdown (KD) increases LNCaP cell proliferation, migration and wound healing, verifying loss drives a cancer phenotype. Endogenous TET2 bound the androgen receptor (AR) and AR-coactivator proteins in LNCaP cell extracts, and TET2 KD increases prostate-specific antigen (KLK3/PSA) expression. Published data reveal TET2 binding sites and hydroxymethylcytosine proximal to KLK3. A gene co-expression network identified using TCGA prostate tumour RNA-sequencing identifies co-regulated cancer genes associated with 2-oxoglutarate (2-OG) and succinate metabolism, including TET2, lysine demethylase (KDM) KDM6A, BRCA1-associated BAP1, and citric acid cycle enzymes IDH1/2, SDHA/B, and FH. The co-expression signature is conserved across 31 TCGA cancers suggesting a putative role for TET2 as an energy sensor (of 2-OG) that modifies aspects of androgen-AR signalling. Decreased TET2 mRNA expression in TCGA PCa tumours is strongly associated with reduced patient survival, indicating reduced expression in tumours may be an informative biomarker of disease progression and perhaps metastatic disease.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Androgênicos/metabolismo , Proliferação de Células/fisiologia , Proteínas de Ligação a DNA/genética , Dioxigenases , Células HEK293 , Humanos , Íntrons , Calicreínas/genética , Calicreínas/metabolismo , Ácidos Cetoglutáricos/metabolismo , Masculino , Polimorfismo de Nucleotídeo Único , Antígeno Prostático Específico/genética , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas/genética , Receptores Androgênicos/genética , Succinatos/metabolismo
3.
J Control Release ; 224: 199-207, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26780173

RESUMO

Transarterial chemoembolization (TACE) is used to treat various types of hypervascular tumors such as hepatocellular carcinoma and renal cancer. However, embolization and blocking of blood vessels nourishing a tumor mass evokes an angiogenic response due to the secretion of vascular endothelial growth factor (VEGF), which results in the formation of new blood vessels and eventually limitation in therapeutic efficacy. The presented work investigates the feasibility of loading the clinically used embolic beads (DC Bead®) with Bevacizumab (BEV), an anti-VEGF antibody, and control its release kinetics via Layer-by-Layer (LbL) coating. This strategy has the aim to achieve high, localized and sustained concentrations of BEV at the tumor site and reduce drug exposure in the systemic circulation. High loading of BEV on lyophilized beads of about 76mg BEV/bead vial was achieved. LbL coating was carried out by depositing alternating layers of the biocompatible polymers alginate and poly-L-lysine. Coating was proven successful by monitoring the reversal of zeta potential after addition of each layer. Morphological changes of the bead surface before and after coating were illustrated using SEM imaging. Moreover, release profiles from different formulations were studied and results showed that optimizing the number of deposited layers effectively slows the release of BEV for three days. Activity of released BEV was studied in different 2D and 3D cell based assays. Released BEV fractions showed comparable activity to fresh BEV solution used as control after 3days. In conclusion, our results suggest the opportunity for loading anti-VEGF antibodies on commercially available embolic beads to increase the efficacy of TACE of hypervascular tumors.


Assuntos
Anticorpos Bloqueadores/administração & dosagem , Anticorpos Bloqueadores/farmacologia , Quimioembolização Terapêutica/métodos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Alginatos , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/uso terapêutico , Bevacizumab/administração & dosagem , Bevacizumab/uso terapêutico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Excipientes , Humanos , Tamanho da Partícula , Polilisina/química , Fator A de Crescimento do Endotélio Vascular/imunologia
4.
Am J Transplant ; 16(3): 960-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26731613

RESUMO

Solid organ transplant recipients have increased colorectal cancer (CRC) risk. We assessed CRC risk among transplant recipients and identified factors contributing to this association. The US transplant registry was linked to 15 population-based cancer registries (1987-2010). We compared CRC risk in recipients to the general population by using standardized incidence ratios (SIRs) and identified CRC risk factors by using Poisson regression. Based on 790 cases of CRC among 224 098 transplant recipients, the recipients had elevated CRC risk (SIR 1.12, 95% confidence interval [CI] 1.04 to 1.20). The increase was driven by an excess of proximal colon cancer (SIR 1.69, 95% CI 1.53 to 1.87), while distal colon cancer was not increased (SIR 0.93, 95% CI 0.80 to 1.07), and rectal cancer was reduced (SIR 0.64, 95% CI 0.54 to 0.76). In multivariate analyses, CRC was increased markedly in lung recipients with cystic fibrosis (incidence rate ratio [IRR] 12.3, 95% CI 6.94 to 21.9, vs. kidney recipients). Liver recipients with primary sclerosing cholangitis and inflammatory bowel disease also had elevated CRC risk (IRR 5.32, 95% CI 3.73 to 7.58). Maintenance therapy with cyclosporine and azathioprine was associated with proximal colon cancer (IRR 1.53, 95% CI 1.05 to 2.23). Incidence was not elevated in a subgroup of kidney recipients treated with tacrolimus and mycophenolate mofetil, pointing to the relevance of the identified risk factors. Transplant recipients have increased proximal colon cancer risk, likely related to underlying medical conditions (cystic fibrosis and primary sclerosing cholangitis) and specific immunosuppressive regimens.


Assuntos
Neoplasias Colorretais/etiologia , Rejeição de Enxerto/etiologia , Transplante de Órgãos/efeitos adversos , Complicações Pós-Operatórias , Sistema de Registros , Adulto , Idoso , Neoplasias Colorretais/epidemiologia , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco , Fatores de Risco , Transplantados , Estados Unidos/epidemiologia
5.
Free Radic Res ; 48(3): 380-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24437375

RESUMO

Both endogenous factors (genomic variations) and exogenous factors (environmental exposures, lifestyle) impact the balance of reactive oxygen species (ROS). Variants of the ND3 (rs2853826; G10398A) gene of the mitochondrial genome, manganese superoxide dismutase (MnSOD; rs4880 Val16Ala) and glutathione peroxidase (GPX-1; rs1050450 Pro198Leu), are purported to have functional effects on regulation of ROS balance. In this study, we examined associations of breast and prostate cancer risks and survival with these variants, and interactions between rs4880-rs1050450, and alcohol consumption-rs2853826. Nested case-control studies were conducted in the Breast and Prostate Cancer Cohort Consortium (BPC3), consisting of nine cohorts. The analyses included over 10726 post-menopausal breast and 7532 prostate cancer cases with matched controls. Logistic regression models were used to evaluate associations with risk, and proportional hazard models were used for survival outcomes. We did not observe significant interactions between polymorphisms in MnSOD and GPX-1, or between mitochondrial polymorphisms and alcohol intake and risk of either breast (p-interaction of 0.34 and 0.98, respectively) or prostate cancer (p-interaction of 0.49 and 0.50, respectively). We observed a weak inverse association between prostate cancer risk and GPX-1 Leu198Leu carriers (OR 0.87, 95% CI 0.79-0.97, p = 0.01). Overall survival among women with breast cancer was inversely associated with G10398 carriers who consumed alcohol (HR 0.66 95% CI 0.49-0.88). Given the high power in our study, it is unlikely that interactions tested have more than moderate effects on breast or prostate cancer risk. Observed associations need both further epidemiological and biological confirmation.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Estresse Oxidativo/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Estresse Oxidativo/fisiologia , Polimorfismo de Nucleotídeo Único , Espécies Reativas de Oxigênio/metabolismo , Análise de Sobrevida
6.
Br J Cancer ; 109(5): 1352-9, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23907431

RESUMO

BACKGROUND: Coffee and tea are commonly consumed and carry potential anticancer components that could reduce the risk of colorectal cancer; however, their relationships with colorectal cancer risk remain inconsistent. METHODS: A prospective analysis was carried out to examine the relationships of coffee and tea intake with colorectal cancer risk in 57,398 men and women in the intervention arm of the National Cancer Institute-Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, a national screening study that limits differential detection biases. Coffee and tea intakes were assessed by food frequency questionnaire. RESULTS: Six hundred and eighty-one incident colorectal cancer cases were ascertained during a median follow-up of 11.4 years. Greater coffee intake was not associated with risk of colorectal cancer (relative risk (RR)=1.08, 95% confidence interval (CI)=0.79-1.48, Ptrend=0.23). Stratifying by cancer site (Pheterogeneity=0.48) or stage (Pheterogeneity=0.83) did not alter the relationship. Associations remained unchanged in subsets of participants for either caffeinated or decaffeinated coffee or when stratifying by several colorectal cancer risk factors. Similarly, greater tea intake was not associated with colorectal cancer risk overall (RR=0.77, 95% CI=0.55-1.09, Ptrend=0.17) or by cancer site (Pheterogeneity=0.14) or stage (Pheterogeneity=0.60). These associations were not modified by several colorectal cancer risk factors. CONCLUSION: The findings of this study do not provide evidence to suggest that drinking coffee or tea is beneficial in protecting against colorectal cancer.


Assuntos
Cafeína , Café/efeitos adversos , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/mortalidade , Chá , Comportamento Alimentar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários
7.
Br J Cancer ; 108(6): 1378-86, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23361049

RESUMO

BACKGROUND: The chromosome 9p21.3 region has been implicated in the pathogenesis of multiple cancers. METHODS: We systematically examined up to 203 tagging SNPs of 22 genes on 9p21.3 (19.9-32.8 Mb) in eight case-control studies: thyroid cancer, endometrial cancer (EC), renal cell carcinoma, colorectal cancer (CRC), colorectal adenoma (CA), oesophageal squamous cell carcinoma (ESCC), gastric cardia adenocarcinoma and osteosarcoma (OS). We used logistic regression to perform single SNP analyses for each study separately, adjusting for study-specific covariates. We combined SNP results across studies by fixed-effect meta-analyses and a newly developed subset-based statistical approach (ASSET). Gene-based P-values were obtained by the minP method using the Adaptive Rank Truncated Product program. We adjusted for multiple comparisons by Bonferroni correction. RESULTS: Rs3731239 in cyclin-dependent kinase inhibitors 2A (CDKN2A) was significantly associated with ESCC (P=7 × 10(-6)). The CDKN2A-ESCC association was further supported by gene-based analyses (Pgene=0.0001). In the meta-analyses by ASSET, four SNPs (rs3731239 in CDKN2A, rs615552 and rs573687 in CDKN2B and rs564398 in CDKN2BAS) showed significant associations with ESCC and EC (P<2.46 × 10(-4)). One SNP in MTAP (methylthioadenosine phosphorylase) (rs7023329) that was previously associated with melanoma and nevi in multiple genome-wide association studies was associated with CRC, CA and OS by ASSET (P=0.007). CONCLUSION: Our data indicate that genetic variants in CDKN2A, and possibly nearby genes, may be associated with ESCC and several other tumours, further highlighting the importance of 9p21.3 genetic variants in carcinogenesis.


Assuntos
Biomarcadores Tumorais/genética , Cromossomos Humanos Par 9/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Metanálise como Assunto , Prognóstico
8.
Am J Physiol Endocrinol Metab ; 303(8): E950-8, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22811468

RESUMO

Human chorionic gonadotropin (hCG) displays a major role in pregnancy initiation and progression and is involved in trophoblast differentiation and fusion. However, the site and the type of dimeric hCG production during the first trimester of pregnancy is poorly known. At that time, trophoblastic plugs present in the uterine arteries disappear, allowing unrestricted flow of maternal blood to the intervillous space. The consequence is an important modification of the trophoblast environment, including a rise of oxygen levels from about 2.5% before 10 wk of amenorrhea (WA) to ∼8% after 12 WA. Two specific ß-hCG proteins that differ from three amino acids have been described: type 1 (CGB7) and type 2 (CGB3, -5, and -8). Here, we demonstrated in situ and ex vivo on placental villi and in vitro in primary cultures of human cytotrophoblasts that type 1 and 2 ß-hCG RNAs and proteins were expressed by trophoblasts and that these expressions were higher before blood enters in the intervillous space (8-9 vs. 12-14 WA). hCG was immunodetected in villous mononucleated cytotrophoblasts (VCT) and syncytiotrophoblast (ST) at 8-9 WA but only in ST at 12-14 WA. Furthermore, hCG secretion was fourfold higher in VCT cultures from 8-9 WA compared with 12-14 WA. Interestingly, VCT from 8-9 WA placentas were found to exhibit more fusion features. Taken together, we showed that type 1 and type 2 ß-hCG are highly expressed by VCT in the early first trimester, contributing to the high levels of hCG found in maternal serum at this term.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/biossíntese , Placenta/metabolismo , Primeiro Trimestre da Gravidez/genética , Primeiro Trimestre da Gravidez/metabolismo , Trofoblastos/metabolismo , Animais , Western Blotting , Fusão Celular , Separação Celular , Células Cultivadas , Gonadotropina Coriônica Humana Subunidade beta/genética , Vilosidades Coriônicas/metabolismo , Feminino , Expressão Gênica/fisiologia , Humanos , Imuno-Histoquímica , Consumo de Oxigênio/fisiologia , Gravidez , RNA/biossíntese , RNA/genética , Reação em Cadeia da Polimerase em Tempo Real
9.
Transl Psychiatry ; 2: e119, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22832964

RESUMO

The identification and exploration of genetic loci that influence smoking behaviors have been conducted primarily in populations of the European ancestry. Here we report results of the first genome-wide association study meta-analysis of smoking behavior in African Americans in the Study of Tobacco in Minority Populations Genetics Consortium (n = 32,389). We identified one non-coding single-nucleotide polymorphism (SNP; rs2036527[A]) on chromosome 15q25.1 associated with smoking quantity (cigarettes per day), which exceeded genome-wide significance (ß = 0.040, s.e. = 0.007, P = 1.84 × 10(-8)). This variant is present in the 5'-distal enhancer region of the CHRNA5 gene and defines the primary index signal reported in studies of the European ancestry. No other SNP reached genome-wide significance for smoking initiation (SI, ever vs never smoking), age of SI, or smoking cessation (SC, former vs current smoking). Informative associations that approached genome-wide significance included three modestly correlated variants, at 15q25.1 within PSMA4, CHRNA5 and CHRNA3 for smoking quantity, which are associated with a second signal previously reported in studies in European ancestry populations, and a signal represented by three SNPs in the SPOCK2 gene on chr10q22.1. The association at 15q25.1 confirms this region as an important susceptibility locus for smoking quantity in men and women of African ancestry. Larger studies will be needed to validate the suggestive loci that did not reach genome-wide significance and further elucidate the contribution of genetic variation to disparities in cigarette consumption, SC and smoking-attributable disease between African Americans and European Americans.


Assuntos
Negro ou Afro-Americano/genética , Fumar/genética , Adulto , Idoso , Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 15/genética , Feminino , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Proteoglicanas/genética , Receptores Nicotínicos/genética , Estatística como Assunto
10.
Br J Cancer ; 106(3): 608-16, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-22166801

RESUMO

BACKGROUND: Most studies of meat and colorectal adenoma have investigated prevalent events from a single screening, thus limiting our understanding of the role of meat and meat-related exposures in early colorectal carcinogenesis. METHODS: Among participants in the screening arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial who underwent baseline and follow-up sigmoidoscopy (n=17,072), we identified 1008 individuals with incident distal colorectal adenoma. We calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations between meat and meat-related components and incident distal colorectal adenoma using multivariate logistic regression. RESULTS: We observed suggestive positive associations for red meat, processed meat, haeme iron, and nitrate/nitrite with distal colorectal adenoma. Grilled meat (OR=1.56, 95% CI=1.04-2.36), well or very well-done meat (OR=1.59, 95% CI=1.05-2.43), 2-amino-1-methyl-6-phenyl-imidazo[4,5-b]pyridine (PhIP) (OR=1.75, 95% CI=1.17-2.64), benzo[a]pyrene (OR=1.53, 95% CI=1.06-2.20), and total mutagenic activity (OR=1.57, 95% CI=1.03-2.40) were positively associated with rectal adenoma. Total iron (diet and supplements) (OR=0.69, 95% CI=0.56-0.86) and iron from supplements (OR=0.65, 95% CI=0.44-0.97) were inversely associated with any distal colorectal adenoma. CONCLUSION: Our findings indicate that several meat-related components may be most relevant to early neoplasia in the rectum. In contrast, total iron and iron from supplements were inversely associated with any distal colorectal adenoma.


Assuntos
Adenoma/epidemiologia , Neoplasias Colorretais/epidemiologia , Carne , Adenoma/etiologia , Idoso , Colo/patologia , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/prevenção & controle , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Sigmoidoscopia , Estados Unidos/epidemiologia
11.
Ophthalmologe ; 109(1): 54-8, 2012 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-22130724

RESUMO

BACKGROUND: As techniques for cataract surgery have evolved, spontaneous intraocular lens (IOL) dislocation in patients with no ocular pathology arises less frequently. We present seven consecutive cases of uncomplicated cataract surgery with early in-the-bag spontaneous intraocular lens dislocation for which the same type of hydrophilic single piece lens was used. MATERIAL AND METHODS: A retrospective analysis was conducted on seven cases involving patients with IOL dislocation who underwent uncomplicated cataract surgery within a period of 4 months (October 2010 to January 2011) using the same type of single piece IOL. The median age of the 7 patients was 73 years and IOL repositioning was performed after an average of 10 weeks. RESULTS: Sulcus repositioning could be carried out in only five of the seven patients and IOL repositioning within the capsule was achieved in one patient. A second patient exhibited IOL dislocation after yttrium aluminium garnet (YAG) laser capsulotomy. Explantation of the IOL and sulcus implantation of another IOL type (Acrysof MA50 MB) was necessary for a third patient. A fourth case presented an angled IOL haptic and dislocation of the IOL in the sulcus position. DISCUSSION: Even after uncomplicated cataract surgery, spontaneous in-the-bag IOL dislocation in patients with no ocular pathology may occur due to a hydrophilic lens material which induces stronger anterior capsular phimosis (ACP) in comparison to alternative materials. In combination with a thin lens design this may result in angled IOL haptics and IOL dislocation. CONCLUSIONS: Careful selection of suitable lens design and material according to individual predisposing factors is necessary. This retrospective case study demonstrates that the combination of hydrophilic lens material and a thin lens design may result in early spontaneous IOL dislocation. Furthermore, as established in one case, YAG laser capsulotomy may induce IOL dislocation if the lens design cannot withstand capsular fibrosis.


Assuntos
Remoção de Dispositivo/métodos , Migração de Corpo Estranho/etiologia , Migração de Corpo Estranho/cirurgia , Lentes Intraoculares/efeitos adversos , Facoemulsificação/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Catarata/complicações , Feminino , Humanos , Masculino , Falha de Tratamento
12.
Oncogene ; 29(20): 3025-32, 2010 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-20208563

RESUMO

ADAMTS (a disintegrin and metalloproteinase domain with thrombospondin motifs) constitute a family of endopeptidases related to matrix metalloproteinases. These proteases have been largely implicated in tissue remodeling and angiogenesis associated with physiological and pathological processes. To elucidate the in vivo functions of ADAMTS-12, we have generated a knockout mouse strain (Adamts12(-/-)) in which Adamts12 gene was deleted. The mutant mice had normal gestations and no apparent defects in growth, life span and fertility. By applying three different in vivo models of angiogenesis (malignant keratinocyte transplantation, Matrigel plug and aortic ring assays) to Adamts12(-/-) mice, we provide evidence for a protective effect of this host enzyme toward angiogenesis and cancer progression. In the absence of Adamts-12, both the angiogenic response and tumor invasion into host tissue were increased. Complementing results were obtained by using medium conditioned by cells overexpressing human ADAMTS-12, which inhibited vessel outgrowth in the aortic ring assay. This angioinhibitory effect of ADAMTS-12 was independent of its enzymatic activity as a mutated inactive form of the enzyme was similarly efficient in inhibiting endothelial cell sprouting in the aortic ring assay than the wild-type form. Altogether, our results show that ADAMTS-12 displays antiangiogenic properties and protect the host toward tumor progression.


Assuntos
Proteínas ADAM/fisiologia , Neoplasias Experimentais/irrigação sanguínea , Neovascularização Patológica/prevenção & controle , Proteínas ADAMTS , Animais , Aorta/citologia , Aorta/metabolismo , Colágeno/metabolismo , Colágeno Tipo I/metabolismo , Combinação de Medicamentos , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Queratinócitos/transplante , Laminina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Invasividade Neoplásica , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Proteoglicanas/metabolismo , Ratos , Ratos Wistar
13.
Occup Environ Med ; 66(12): 848-53, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19773279

RESUMO

INTRODUCTION: Benzene is an established human haematotoxin, with substantial interindividual variation in benzene-induced toxicity. METHODS: To further examine if genetic variation contributes to benzene haematotoxicity, we analysed 1023 tagSNPs in 121 gene regions important for benzene metabolism, haematopoiesis, leukaemia and lymphoma among 250 workers exposed to benzene and 140 unexposed controls in a cross-sectional study carried out in China. Linear regression was used to analyse the relationship between genetic polymorphisms and total white blood cell (WBC) count and its subtypes, adjusting for potential confounders and occupational exposure to benzene and toluene among exposed workers. The minp test assessed the association on the gene region level. The false discovery rate method was used to control for multiple comparisons. RESULTS: VEGF (minp = 0.0030) and ERCC3 (minp = 0.0042) were the most significantly associated gene regions with altered WBC counts among benzene-exposed workers, after accounting for multiple comparisons. Highly significant changes were also found for WBC subtype counts, including granulocytes, CD4+ T cells and lymphocytes for VEGF and granulocytes and NK cells for ERCC3. Further, in workers exposed to <1 ppm, a SNP in VEGF was associated with changes in WBC and granulocyte counts, and SNPs in ERCC3 were associated with changes in WBC, NK cell and granulocyte counts. DISCUSSION: Our findings suggest that genetic variation in VEGF, which plays an important role in blood vessel growth, and ERCC3, which is a member of the DNA repair pathway and is responsible for repairing bulky DNA adducts formed by chemicals, may contribute to individual susceptibility to benzene-induced haematotoxicity at relatively low levels of benzene exposure.


Assuntos
Benzeno/toxicidade , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Doenças Hematológicas/induzido quimicamente , Doenças Profissionais/induzido quimicamente , Fator A de Crescimento do Endotélio Vascular/genética , Feminino , Predisposição Genética para Doença , Doenças Hematológicas/sangue , Doenças Hematológicas/genética , Humanos , Contagem de Leucócitos , Leucócitos/efeitos dos fármacos , Masculino , Doenças Profissionais/sangue , Doenças Profissionais/genética , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Polimorfismo de Nucleotídeo Único
14.
Br J Cancer ; 100(5): 822-8, 2009 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-19259097

RESUMO

Autoimmune conditions are associated with an elevated risk of lymphoproliferative malignancies, but few studies have investigated the risk of myeloid malignancies. From the US Surveillance Epidemiology and End Results (SEER)-Medicare database, 13 486 myeloid malignancy patients (aged 67+ years) and 160 086 population-based controls were selected. Logistic regression models adjusted for gender, age, race, calendar year and number of physician claims were used to estimate odds ratios (ORs) for myeloid malignancies in relation to autoimmune conditions. Multiple comparisons were controlled for using the Bonferroni correction (P<0.0005). Autoimmune conditions, overall, were associated with an increased risk of acute myeloid leukaemia (AML) (OR 1.29) and myelodysplastic syndrome (MDS, OR 1.50). Specifically, AML was associated with rheumatoid arthritis (OR 1.28), systemic lupus erythematosus (OR 1.92), polymyalgia rheumatica (OR 1.73), autoimmune haemolytic anaemia (OR 3.74), systemic vasculitis (OR 6.23), ulcerative colitis (OR 1.72) and pernicious anaemia (OR 1.57). Myelodysplastic syndrome was associated with rheumatoid arthritis (OR1.52) and pernicious anaemia (OR 2.38). Overall, autoimmune conditions were not associated with chronic myeloid leukaemia (OR 1.09) or chronic myeloproliferative disorders (OR 1.15). Medications used to treat autoimmune conditions, shared genetic predisposition and/or direct infiltration of bone marrow by autoimmune conditions, could explain these excess risks of myeloid malignancies.


Assuntos
Doenças Autoimunes/complicações , Síndromes Mielodisplásicas/etiologia , Doenças Mieloproliferativas-Mielodisplásicas/etiologia , Transtornos Mieloproliferativos/etiologia , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/epidemiologia , Feminino , Humanos , Masculino , Síndromes Mielodisplásicas/epidemiologia , Doenças Mieloproliferativas-Mielodisplásicas/epidemiologia , Transtornos Mieloproliferativos/epidemiologia , Razão de Chances , Fatores de Risco , Fatores de Tempo
15.
Gynecol Obstet Invest ; 64(3): 156-60, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17934312

RESUMO

The specific interaction of blastocyst-derived human chorionic gonadotropin (hCG) and endometrial LH/hCG-R constitutes a fundamental component of the molecular dialogue at the materno-fetal interface. From our observations and studies from other groups, hCG was indeed shown to play a significant role in implantation and tolerance of the embryo, decidual differentiation and remodeling, as well as in placentation. The profile pattern of LH/hCG-R expression by endometrial epithelium correlates with the theoretical timing of the implantation window. Studies are currently being conducted in assisted medical procreation and in an animal model of implantation to establish the index of LH/hCG-R expression as a new biomarker of uterine receptivity for embryo implantation.


Assuntos
Blastocisto/fisiologia , Gonadotropina Coriônica/fisiologia , Implantação do Embrião/fisiologia , Endométrio/fisiologia , Gravidez/fisiologia , Receptores do LH/fisiologia , Feminino , Humanos , Hormônio Luteinizante/fisiologia
16.
Ophthalmologe ; 104(10): 875-9, 2007 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-17653725

RESUMO

OBJECTIVE: The critical dose of chloroquine/hydroxychloroquine leading to a maculopathy or generalised retinopathy remains undetermined. In the literature, 100 g is considered the dose at which regular vision checks should be performed. Generally, chloroquine is said to be more toxic than hydroxychloroquine. A young patient presenting with toxic maculopathy after 57 g of hydroxychloroquine and a daily dosage of 2 mg/kg body weight prompted us to retrospectively look at our patients examined in this respect over about 1 year. METHODS: The data of patients who were examined because of chloroquine/hydroxychloroquine intake or a respective maculopathy/retinopathy were retrospectively analysed. The time period was January 2005 until March 2006. Retinal damage was defined by fundus changes and alteration of the multifocal electroretinogram (ERG). RESULTS: Twenty-one patients--18 women and three men--were examined. The mean age was 51 years (range 6-71). Five of the nine chloroquine-treated patients developed a maculopathy, and one of them developed an additional generalised retinopathy. Of the patients treated by hydroxychloroquine, three of 12 suffered from a maculopathy and one from an additional generalised retinopathy. The cumulative doses leading to retinal damage ranged from 170 g to 1650 g for chloroquine and from 57 g to 1190 g for hydroxychloroquine. The highest cumulative doses without leading to signs of retinopathy were 790 g for chloroquine and 1200 g for hydroxychloroquine. CONCLUSIONS: There is a high variability of cumulative doses of chloroquine/hydroxychloroquine that lead to a toxic retinopathy. Therefore, early and regular ophthalmologic examinations are recommended. Electrophysiological testing should be performed once a year, corresponding to about 60 g of base with one tablet a day. For electrophysiology, the multifocal ERG has turned out to be the most important test in this regard. However, visual acuity and funduscopy should be performed more frequently.


Assuntos
Antirreumáticos/toxicidade , Cloroquina/toxicidade , Hidroxicloroquina/toxicidade , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Retina/efeitos dos fármacos , Doenças Retinianas/induzido quimicamente , Adolescente , Adulto , Idoso , Azatioprina/administração & dosagem , Azatioprina/toxicidade , Criança , Cloroquina/administração & dosagem , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Eletrorretinografia/efeitos dos fármacos , Feminino , Fundo de Olho , Humanos , Hidroxicloroquina/administração & dosagem , Assistência de Longa Duração , Macula Lutea/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Oftalmoscopia , Prednisolona/administração & dosagem , Prednisolona/toxicidade , Doenças Retinianas/diagnóstico , Campos Visuais/efeitos dos fármacos
17.
Solid State Nucl Magn Reson ; 27(1-2): 122-31, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15589733

RESUMO

The motion of silver ions in (AgI)x-(Ag2O-B2O3)1-x glasses with AgI concentrations of x=0.5 and 0.7 was studied using 109Ag-NMR. The NMR spectra were analyzed in terms of a superposition of two different contributions. These are associated with Ag ions, which hop on vastly different time scales. The existence of dynamic heterogeneity, i.e. the existence of slow and of fast contributions to the hopping dynamics was directly demonstrated using a four-time stimulated-echo experiment. The results are compatible with an intrinsically exponential response. From measurements of the spectra and of two-time correlation functions a Gaussian distribution of energy barriers, hindering the ionic motion, could be mapped out.

18.
Hum Reprod ; 19(11): 2633-43, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15388676

RESUMO

BACKGROUND: The elucidation of the molecular mechanisms by which the embryo contributes to its implantation is an area of extensive research. The main objective of this study was to investigate the pattern of leukemia inhibitory factor (LIF) and interleukin-6 (IL-6) secretion by human endometrial epithelium, and their regulation by human chorionic gonadotropin (hCG) and other growth factors present at the embryonic-endometrial interface. METHODS: Endometrial epithelial cells (EEC) were isolated from biopsies collected at both proliferative and secretory phases of fertile women. RESULTS: HCG (1-50 IU/ml) increased LIF secretion by EEC cultures derived from follicular phase (up to 285+/-75%) or from secretory phase (up to 212+/-16%). In contrast, hCG reduced IL-6 secretion by EEC in both phases. The hCG/LH receptor gene was transcribed by EEC as evidenced by RT-PCR. Insulin-like growth factors 1 and 2 increased LIF secretion by EEC. Transforming growth factor beta1 stimulated LIF and reduced IL-6 secretion. CONCLUSIONS: Through hCG, the blastocyst may be involved in the control of its implantation (via an increase of proimplantatory LIF) and tolerance (via an inhibition of proinflammatory IL-6). Other growth factors present at the embryonic-endometrial interface are also involved in the control of LIF and IL-6 endometrial secretion.


Assuntos
Gonadotropina Coriônica/fisiologia , Endométrio/metabolismo , Substâncias de Crescimento/fisiologia , Interleucina-6/metabolismo , Proteínas/metabolismo , Adolescente , Adulto , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Citocinas/metabolismo , Implantação do Embrião , Endométrio/citologia , Endométrio/efeitos dos fármacos , Epitélio/metabolismo , Feminino , Substâncias de Crescimento/farmacologia , Humanos , Fator Inibidor de Leucemia , Ciclo Menstrual/fisiologia , Pessoa de Meia-Idade , Receptores do LH/efeitos dos fármacos , Receptores do LH/genética , Receptores do LH/metabolismo
19.
Vet Res Commun ; 28(3): 225-34, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15074768

RESUMO

Thirty-nine leaf samples of Narthecium ossifragum collected from eight sites in Møre og Romsdal County, Norway, during June-September 1997 and 41 leaf samples collected at five sites in the same county during June-August 1998 were analysed for the concentrations of steroidal sapogenins using GC-MS. The 1998 samples were also examined for fungal elements (conidia and hyphae) after incubation in a moist chamber for 10-14 days. The highest 1997 and 1998 leaf sapogenin concentrations (4881 and 7115 mg/kg dry matter, respectively) were 13-14 times greater than the lowest sapogenin concentrations found (344 and 531 mg/kg dry matter, respectively). The results did not reveal systematic differences in sapogenin concentrations between the two seasons, or between samples harvested early or late in the same seasons, or between sapogenin concentrations in plants harvested at different sites. Cladosporium magnusianum was the predominant fungus found in the samples. The degree of fungal infection on the samples was in generally low, but the number of C. magnusianum colonies in the moist chamber preparations and fungal elements (conidia and hyphae) in leaf washings and on leaves tended to increase with time. Factor analysis and multiple regression analysis performed on the chemical and fungal results suggest that sporulation may have occurred in the fungi in response to increase in sapogenin concentrations.


Assuntos
Cladosporium/crescimento & desenvolvimento , Liliaceae/metabolismo , Liliaceae/microbiologia , Doenças das Plantas/microbiologia , Plantas Tóxicas/microbiologia , Sapogeninas/metabolismo , Análise Fatorial , Noruega , Folhas de Planta/microbiologia , Análise de Regressão , Estações do Ano
20.
Fortschr Neurol Psychiatr ; 71(2): 67-71, 2003 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-12579469

RESUMO

Primary central nervous system lymphoma of non-Hodgkin's type are distinguished from systemic non-Hodgkin's lymphoma because of their different pathobiological behaviour. Predisposing factors are pharmacologically induced immunosuppression and those referring to diseases. We present the case of a patient who was sent to hospital in case of emergency due to pain of one half of the face. The symptoms corresponded essentially to neuralgia of the trigeminal nerve. During course other neurological symptoms showed up. The right diagnoses of a primary central nervous system lymphoma of non-hodgkin's type was finally made post mortem. The case especially reveals the difficulties of diagnosis - including negative and confusing MRI-findings - and the variety of differential diagnosis of this also in not immunosuppressed persons more and more frequent kind of tumor.


Assuntos
Neoplasias do Sistema Nervoso Central/complicações , Linfoma não Hodgkin/complicações , Neuralgia do Trigêmeo/etiologia , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/patologia , Evolução Fatal , Humanos , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/patologia , Imageamento por Ressonância Magnética , Masculino , Dor/etiologia , Neuralgia do Trigêmeo/diagnóstico , Neuralgia do Trigêmeo/patologia
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