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1.
PLoS Negl Trop Dis ; 8(7): e2944, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24992686

RESUMO

UNLABELLED: Neurocysticercosis is a frequent parasitic infection of the human brain, occurring in most of the world, and requires imaging of the brain to diagnose. To determine the burden of disease and to simplify diagnosis, a field-friendly rapid lateral flow (LF) based antibody screening test was developed. The assay utilizes novel nano-sized up-converting phosphor (UCP) reporter particles in combination with a portable lightweight analyzer and detects antibodies in serum samples reactive with bacterial-expressed recombinant (r) T24H, a marker for detecting neurocysticercosis cases. Three sequential flow steps allow enrichment of antibodies on the Test (T) line and consecutive binding of protein-A coated UCP reporter particles. Antibody binding was determined by measuring 550 nm emission after excitation of the UCP label with a 980 nm infrared (IR) diode. Clinical sensitivity and specificity of the assay to detect cases of human neurocysticercosis with 2 or more viable brain cysts were 96% and 98%, respectively, using a sample set comprised of sera from 63 confirmed cases and 170 healthy parasite-naïve non-endemic controls. IN CONCLUSION: Proof-of-principle, of a rapid UCP-LF screening assay for neurocysticercosis was demonstrated. The assay utilized bacterial-expressed rT24H as a potential alternative for baculovirus-expressed rT24H. Performance of the UCP-LF assay was excellent, although further studies need to confirm that bacterial expressed antigen can entirely replace previously used baculovirus antigen. In addition, the increasing availability of commercial sources for UCP reporter materials as well as the accessibility of affordable semi-handheld scanners may allow UCP-based bioanalytical systems for point-of-care to evolve at an even faster pace.


Assuntos
Imunoensaio , Nanoestruturas , Doenças Negligenciadas , Neurocisticercose/diagnóstico , Parasitologia , Estudos de Viabilidade , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Nanotecnologia , Doenças Negligenciadas/diagnóstico , Doenças Negligenciadas/imunologia , Parasitologia/instrumentação , Parasitologia/métodos , Sensibilidade e Especificidade
2.
Anal Bioanal Chem ; 405(23): 7367-75, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23836086

RESUMO

Monitoring levels of biologicals against tumor necrosis factor (TNF) has been suggested to improve therapeutic outcomes in inflammatory bowel diseases (IBDs). This pilot study describes a rapid lateral flow (LF)-based assay for on-site monitoring of serum trough levels of humanized monoclonal antibody infliximab (IFX). The applied chromatographic method utilizes sequential flows of diluted serum, wash buffer, and an immunoglobulin generic label on LF strips with a Test line comprised of TNF-α. The successive flows permitted enrichment of IFX at the Test line before the label was applied. The label, luminescent upconverting phosphor (UCP) particles coated with protein-A, emits a 550-nm visible light upon excitation with 980-nm infrared light. IFX concentrations were determined through measurement of UCP fluorescence at the Test line. The assay was optimized to detect IFX levels as low as 0.17 µg/mL in serum. For patients with IBD, this limit is appropriate to detect levels associated with loss of response (0.5 µg IFX/mL). The assay was evaluated with clinical samples from patients with Crohn's disease and correlated well within the physiologically relevant range from 0.17 to 10 µg/mL with an IFX-specific ELISA. Performance of the assay was further successfully validated with samples from blood donors, IFX negative IBD patients, and rheumatoid arthritis patients that had developed anti-IFX antibodies. Because of its generic nature, the assay is suited for detecting most therapeutic anti-TNF-α monoclonal antibodies.


Assuntos
Anticorpos Monoclonais/sangue , Bioensaio/métodos , Doença de Crohn/sangue , Medições Luminescentes/métodos , Anticorpos Anti-Idiotípicos/sangue , Anticorpos Anti-Idiotípicos/química , Anticorpos Monoclonais/uso terapêutico , Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Bioensaio/normas , Doença de Crohn/tratamento farmacológico , Doença de Crohn/imunologia , Estudos de Viabilidade , Humanos , Infliximab , Limite de Detecção , Medições Luminescentes/normas , Fósforo/química , Ligação Proteica , Coloração e Rotulagem , Proteína Estafilocócica A/química , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/sangue
3.
Cell Oncol (Dordr) ; 35(5): 367-75, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22945509

RESUMO

AIM: Locoregional recurrences and distant metastases in adequately treated head and neck squamous cell carcinoma (HNSCC) patients have a dismal effect on survival. Tumor cells that escape histopathological detection might be the prime cause of this effect. We evaluated whether minimal residual cancer (MRC) in deep surgical margins and disseminated tumor cells (DTCs) in bone marrow aspirates are associated with clinicohistopathological parameters and outcome. METHODS: Submucosal samples of deep resection margins of 105 HNSCC patients with histopathologically tumor-free surgical margins were analysed for the presence of MRC using hLy-6D qRT-PCR. Bone-marrow aspirates of 76 of these patients were analysed for DTCs by immunocytochemical staining. Presence of molecular-positive deep surgical margins, presence of DTC in bone marrow aspirates, and clinicohistopathological parameters were tested for associations with survival parameters by univariate and multivariate analyses. RESULTS: In addition to lymph node stage, it appeared that vasoinvasive growth and particularly infiltrative growth pattern are significant predictors for locoregional recurrence (p = 0.041 and p = 0.006, respectively) and disease-free survival (p = 0.014 and p = 0.008, respectively). Remarkably, neither the presence of molecular-positive deep surgical margins nor that of DTC in bone marrow aspirates were significantly related to outcome. CONCLUSIONS: The presence of vasoinvasive and infiltrative growth in HNSCC tumor specimens are significant risk-factors for locoregional recurrence and disease-free survival. At present there seems no role for molecular analysis of deep surgical margins and bone marrow aspirates in predicting outcome with the methods used.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/genética , Técnicas de Diagnóstico Molecular , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Medula Óssea/patologia , Intervalo Livre de Doença , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Neoplasia Residual/patologia , Modelos de Riscos Proporcionais , Coloração e Rotulagem , Adulto Jovem
4.
J Gerontol A Biol Sci Med Sci ; 67(5): 456-64, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22080500

RESUMO

Respiratory chain function becomes less efficient with age resulting in increased levels of damaging reactive oxygen species. We compared rotenone-exposed fibroblast strains from young and old subjects and from offspring of nonagenarian siblings and the partners of the offspring. Rotenone increased reactive oxygen species levels, inhibited growth rate, and increased telomere shortening (all p < .05). Non-stressed strains from young subjects showed lower reactive oxygen species levels (p = .031) and higher growth rates (p = .002) than strains from old subjects. Stressed strains from young subjects showed smaller increases in reactive oxygen species levels (p = .014) and larger decreases in growth rate (p < .001) than strains from old subjects. Telomere-shortening rates were not different between groups. Stress-induced decreases in growth rate were larger in strains from offspring than from partners (p = .05). Strains from young and old subjects are differentially affected by chronic inhibition of the respiratory chain. Changed growth rates in strains from offspring resemble those from strains from young subjects.


Assuntos
Envelhecimento/fisiologia , Transporte de Elétrons/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Rotenona/farmacologia , Fatores Etários , Idoso de 80 Anos ou mais , Biópsia , Células Cultivadas , Feminino , Citometria de Fluxo , Humanos , Modelos Lineares , Masculino , Países Baixos , Espécies Reativas de Oxigênio/metabolismo , Encurtamento do Telômero , beta-Galactosidase/metabolismo
5.
Nucleus ; 2(3): 208-18, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21818414

RESUMO

Increased aggregation of misfolded proteins is associated with aging, and characterizes a number of neurodegenerative disorders caused by homopolymeric amino acid expansion mutations. PABPN1 is an aggregation-prone nuclear protein. Natural aggregation of wild-type (WT) PABPN1 is not known to be disease-associated, but alanine-expanded PABPN1 (expPABPN1) accumulates in insoluble intranuclear inclusions in muscle of patients with oculopharyngeal muscular dystrophy (OPMD). We applied microscopic image quantification to study PABPN1 aggregation process in living cells. We identified transitional pre-inclusion foci and demonstrate that these structures significantly differ between WT- and expPABPN1-expressing cells, while inclusions of these proteins are indistinguishable. In addition to the immobile PABPN1 in inclusions, in the nucleoplasm of expPABPN1 expressing cells we also found a fraction of immobile proteins, representing pre-aggregated species. We found that pre-aggregated and pre-inclusion structures are reverted by a PABPN1 specific affinity binder while inclusion structures are not. Together our results demonstrate that the aggregation process of WT- and expPABPN1 differs in steps preceding inclusion formation, suggesting that pre-aggregated protein species could represent the cytotoxic structures.


Assuntos
Corpos de Inclusão Intranuclear/metabolismo , Proteína II de Ligação a Poli(A)/química , Multimerização Proteica , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Corpos de Inclusão Intranuclear/genética , Mutação , Proteína II de Ligação a Poli(A)/genética , Proteína II de Ligação a Poli(A)/metabolismo , Estrutura Quaternária de Proteína , Fatores de Tempo
6.
BMC Cell Biol ; 11: 34, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20492670

RESUMO

BACKGROUND: In cytokinesis, when the cleavage furrow has been formed, the two centrioles in each daughter cell separate. It has been suggested that the centrioles facilitate and regulate cytokinesis to some extent. It has been postulated that termination of cytokinesis (abscission) depends on the migration of a centriole to the intercellular bridge and then back to the cell center. To investigate the involvement of centrioles in cytokinesis, we monitored the movements of centrioles in three mammalian epithelial cell lines, HeLa, MCF 10A, and the p53-deficient mouse mammary tumor cell line KP-7.7, by time-lapse imaging. Centrin1-EGFP and alpha-Tubulin-mCherry were co-expressed in the cells to visualize respectively the centrioles and microtubules. RESULTS: Here we report that separated centrioles that migrate from the cell pole are very mobile during cytokinesis and their movements can be characterized as 1) along the nuclear envelope, 2) irregular, and 3) along microtubules forming the spindle axis. Centriole movement towards the intercellular bridge was only seen occasionally and was highly cell-line dependent. CONCLUSIONS: These findings show that centrioles are highly mobile during cytokinesis and suggest that the repositioning of a centriole to the intercellular bridge is not essential for controlling abscission. We suggest that centriole movements are microtubule dependent and that abscission is more dependent on other mechanisms than positioning of centrioles.


Assuntos
Centríolos/metabolismo , Células Epiteliais/metabolismo , Microtúbulos/metabolismo , Animais , Biomarcadores/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Centríolos/ultraestrutura , Proteínas Cromossômicas não Histona/metabolismo , Citocinese , Células Epiteliais/ultraestrutura , Células HeLa , Humanos , Mamíferos , Camundongos , Microscopia , Microtúbulos/ultraestrutura , Tubulina (Proteína)/metabolismo
7.
BMC Cancer ; 10: 153, 2010 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-20406480

RESUMO

BACKGROUND: Large number of patients with colorectal liver metastasis show recurrent disease after curative surgical resection. Identification of these high-risk patients may guide therapeutic strategies. The aim of this study was to evaluate whether the presence of disseminated tumor cells in bone marrow from patients undergoing surgical resection of colorectal liver metastases can predict clinical outcome. METHODS: Sixty patients with colorectal liver metastases were planned for a curative resection between 2001 and 2007. All patients underwent bone marrow aspiration before surgery. Detection of tumor cells was performed using immunocytochemical staining for cytokeratin (CK-ICC) combined with automated microscopy or indirectly using reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Disseminated tumor cells were found in 15 of the 46 patients (33%) using CK-ICC and in 9 of 44 of the patients (20%) using RT-PCR. Patients with negative results for RT-PCR had a significant better disease-free survival after resection of their liver metastases (p = 0.02). This group also showed significant better overall survival (p = 0.002). CK-ICC did not predict a worse clinical outcome. CONCLUSIONS: The presence of disseminated tumor cells in bone marrow detected using RT-PCR did predict a worse clinical outcome. The presence of cells detected with CK-ICC did not correlate with poor prognosis.


Assuntos
Biomarcadores Tumorais/análise , Exame de Medula Óssea/métodos , Medula Óssea/patologia , Neoplasias Colorretais/patologia , Imuno-Histoquímica , Queratinas/análise , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Células Neoplásicas Circulantes/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Idoso , Biomarcadores Tumorais/genética , Biópsia por Agulha , Medula Óssea/química , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Queratinas/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Células Neoplásicas Circulantes/química , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
8.
Int J Cancer ; 126(11): 2644-52, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19676050

RESUMO

Up to 30% of stage II patients with curatively resected colorectal cancer (CRC) will develop disease recurrence. We evaluated whether examination of lymph nodes by multilevel sectioning and immunohistochemical staining can improve prognostication. Lymph nodes (n = 780) from 36 CRC patients who had developed disease recurrence (cases) and 72 patients who showed no recurrence of disease for at least 5 years (controls) were analyzed. Sections of 4 levels at 200-microm interval were immunohistochemically stained for cytokeratin expression. The first level was analyzed by conventional and automated microscopy, and the 3 following levels were analyzed by automated microscopy for the presence of tumor cells. Overall, cases showed more micrometastases (3 patients) than controls (1 patient). Analysis of a second level led to the additional detection of 1 patient with micrometastases (case) and 1 patient with macrometastasis (case). Examining more levels only led to additional isolated tumor cells, which were equally divided between cases and controls. Likewise, automated microscopy resulted only in detection of additional isolated tumor cells when compared with conventional microscopy. In multivariate analysis, micrometastases [odds ratio (OR) 26.3, 95% confidence interval (CI) 1.9-364.8, p = 0.015], T4 stage (OR 4.8, 95% CI 1.4-16.7, p = 0.013) and number of lymph nodes (OR 0.9, 95% CI 0.8-1.0, p = 0.028) were independent predictors for disease recurrence. Lymph node analysis of 2 levels and immunohistochemical staining add to the detection of macrometastases and micrometastases in CRC. Micrometastases were found to be an independent predictor of disease recurrence. Isolated tumor cells were of no prognostic significance.


Assuntos
Neoplasias Colorretais/patologia , Linfonodos/patologia , Metástase Neoplásica/patologia , Idoso , Neoplasias Colorretais/classificação , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/terapia , Terapia Combinada , Intervalos de Confiança , Feminino , Humanos , Imuno-Histoquímica/métodos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
9.
Mol Biol Cell ; 20(22): 4804-15, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19793919

RESUMO

The cell nucleus harbors a variety of different bodies that vary in number, composition, and size. Although these bodies coordinate important nuclear processes, little is known about how they are formed. Among the most intensively studied bodies in recent years is the PML body. These bodies have been implicated in gene regulation and other cellular processes and are disrupted in cells from patients suffering from acute promyelocytic leukemia. Using live cell imaging microscopy and immunofluorescence, we show in several cell types that PML bodies are formed at telomeric DNA during interphase. Recent studies revealed that both SUMO modification sites and SUMO interaction motifs in the promyelocytic leukemia (PML) protein are required for PML body formation. We show that SMC5, a component of the SUMO ligase MMS21-containing SMC5/6 complex, localizes temporarily at telomeric DNA during PML body formation, suggesting a possible role for SUMO in the formation of PML bodies at telomeric DNA. Our data identify a novel role of telomeric DNA during PML body formation.


Assuntos
DNA/metabolismo , Corpos de Inclusão/metabolismo , Telômero/genética , Animais , Células Cultivadas , DNA/genética , Humanos , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteína da Leucemia Promielocítica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Telômero/metabolismo , Proteína 1 de Ligação a Repetições Teloméricas/genética , Proteína 1 de Ligação a Repetições Teloméricas/metabolismo , Proteína 2 de Ligação a Repetições Teloméricas/genética , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
10.
Aging Cell ; 8(5): 595-603, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19681808

RESUMO

Unlike various model organisms, cellular responses to stress have not been related to human longevity. We investigated cellular responses to stress in skin fibroblasts that were isolated from young and very old subjects, and from offspring of nonagenarian siblings and their partners, representatives of the general population. Fibroblasts were exposed to rotenone and hyperglycemia and assessed for senescence-associated beta-galactosidase (SA-beta-gal) activity by flow cytometry. Apoptosis/cell death was measured with the Annexin-V/PI assay and cell-cycle analysis (Sub-G1 content) and growth potential was determined by the colony formation assay. Compared with fibroblasts from young subjects, baseline SA-beta-gal activity was higher in fibroblasts from old subjects (P = 0.004) as were stress-induced increases (rotenone: P < 0.001, hyperglycemia: P = 0.027). For measures of apoptosis/cell death, fibroblasts from old subjects showed higher baseline levels (Annexin V+/PI+ cells: P = 0.040, Sub-G1: P = 0.014) and lower stress-induced increases (Sub-G1: P = 0.018) than fibroblasts from young subjects. Numbers and total size of colonies under nonstressed conditions were higher for fibroblasts from young subjects (P = 0.017 and 0.006, respectively). Baseline levels of SA-beta-gal activity and apoptosis/cell death were not different between fibroblasts from offspring and partner. Stress-induced increases were lower for SA-beta-gal activity (rotenone: P = 0.064, hyperglycemia: P < 0.001) and higher for apoptosis/cell death (Annexin V+/PI- cells: P = 0.041, Annexin V+/PI+ cells: P = 0.008). Numbers and total size of colonies under nonstressed conditions were higher for fibroblasts from offspring (P = 0.001 and 0.024, respectively) whereas rotenone-induced decreases were lower (P = 0.008 and 0.004, respectively). These data provide strong support for the hypothesis that in vitro cellular responses to stress reflect the propensity for human longevity.


Assuntos
Envelhecimento/fisiologia , Senescência Celular/fisiologia , Fibroblastos/fisiologia , Envelhecimento da Pele/fisiologia , Fenômenos Fisiológicos da Pele , Estresse Fisiológico/fisiologia , Adulto , Idoso de 80 Anos ou mais , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Feminino , Fibroblastos/efeitos dos fármacos , Nível de Saúde , Humanos , Longevidade , Masculino , Estresse Oxidativo/genética , Rotenona/farmacologia , Irmãos , Fumar , beta-Galactosidase/metabolismo
11.
Cell Oncol ; 31(3): 169-78, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19478385

RESUMO

BACKGROUND: For stage I-II colon cancer a significant number (5-25%) of patients has recurrent disease within 5 years. There is need to identify these high-risk patients as they might benefit from additional treatment. Stroma-tissue surrounding the cancer cells plays an important role in the tumor behavior. The proportion of intra-tumor stroma was evaluated for the identification of high-risk patients. In addition, protein expression of markers involved in pathways related to stroma production and epithelial-to-mesenchymal transition (EMT) was analyzed: beta-catenin, TGF-beta-R2 and SMAD4. METHODS: In a retrospective study of 135 patients with stage I-II colon cancer, the amount of stroma was estimated on routine haematoxylin-eosin stained histological sections. Sections were also immunohistochemically stained for beta-catenin, TGF-beta-R2 and SMAD4. RESULTS: Of 135 analyzed patients 34 (25.2%) showed a high proportion of stroma (stroma-high) and 101 (74.8%) a low proportion (stroma-low). Significant differences in overall-survival and disease-free-survival were observed between the two groups, with stroma-high patients showing poor survival (OS p<0.001, HZ 2.73, CI 1.73-4.30; DFS p<0.001, HZ 2.43, CI 1.55-3.82). A high-risk group was identified with stroma-high and SMAD4 loss (OS p=0.008, HZ 7.98, CI 4.12-15.44, DFS p=0.005, HZ 6.57, CI 3.43-12.56); 12 of 14 (85.7%) patients died within 3 years. In a logistic-regression analysis a high proportion of stroma and SMAD4 loss were strongly related (HZ 5.42, CI 2.13-13.82, p<0.001). CONCLUSIONS: Conventional haematoxylin-eosin stained tumor slides contain more prognostic information than previously fathomed. This can be unleashed by assessing the tumor-stroma ratio. The combination of analyzing the tumor-stroma ratio and staining for SMAD4 results in an independent parameter for confident prediction of clinical outcome.


Assuntos
Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Proteína Smad4/genética , Células Estromais/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Proteína Smad4/metabolismo , Análise de Sobrevida
12.
Cell Oncol ; 31(3): 191-201, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19478387

RESUMO

BACKGROUND: Inherited mutations in the tumour suppressor gene BRCA2 greatly increase the risk of developing breast, ovarian and other types of cancers. So far, most studies have focused on the role of BRCA-pathways in the maintenance of genomic stability. In this study we investigated the potential role of the BRCA2 protein in cytokinesis in unmodified primary human fibroblast carrying a heterozygous mutation in the BRCA2 gene. METHODS: Cell divisions were monitored with time lapse live-cell imaging. BRCA2 mRNA expression levels in BRCA2+/- and BRCA2+/+ cells were quantified with quantitative real-time polymerase chain reaction (qRT-PCR). To investigate the localization of the BRCA2 protein during cytokinesis, immunofluorescence staining using antibody directed against BRCA2 was carried out. Immunofluorescence staining was performed directly after live-cell imaging and cells with delayed cytokinesis, of which the co-ordinates were saved, were automatically repositioned and visualized. RESULTS: We demonstrate that unmodified primary human fibroblasts derived from heterozygous BRCA2 mutation carriers show significantly prolonged cytokinesis. A Subset of the BRCA2+/- cells had delayed cytokinesis (40 min or longer) making the mean cell division time 6 min longer compared with BRCA2+/+ cells, 33 min versus 27 min, respectively. Lower BRCA2 mRNA expression levels were observed in the BRCA2 heterozygous samples compared with the BRCA2 wild type samples. The BRCA2 protein localizes and accumulates to the midbody during cytokinesis, and no difference was detected in distribution and localization of the protein between BRCA2+/- and BRCA2+/+ samples or cells with delayed cytokinesis and normal division time. CONCLUSIONS: The delayed cytokinesis phenotype of the BRCA2 heterozygous cells and localization of the BRCA2 protein to the midbody confirms that BRCA2 plays a role in cytokinesis. Our observations indicate that in a subset of cells the presence of only one wild type BRCA2 allele is insufficient for efficient cytokinesis.


Assuntos
Proteína BRCA2/genética , Citocinese , Fibroblastos/citologia , Mutação , Proteína BRCA2/metabolismo , Células Cultivadas , Fibroblastos/metabolismo , Heterozigoto , Humanos
13.
Clin Cancer Res ; 15(7): 2259-68, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19318479

RESUMO

PURPOSE: Ewing sarcoma is an aggressive sarcoma and is the second most common bone sarcoma in childhood. Disease-specific t(11;22) ( approximately 85-90%), t(21;22) ( approximately 5-10%), or rarer variant translocations with the involvement of chromosome 22 ( approximately 5%) are present. At the gene level, the EWSR1 gene fuses with FLI1, ERG, or other ETS transcription factor family members. Thus far, no Ewing sarcoma has been identified with a fusion to transcription factors other than ETS. EXPERIMENTAL DESIGN: Using molecular tools such as multicolor fluorescence in situ hybridization and array comparative genomic hybridization, a ring chromosome containing chromosomes 20 and 22 was identified in four Ewing sarcoma cases. The breakpoint was mapped with (fiber-) fluorescence in situ hybridization and reverse transcription-PCR followed by sequencing of the fusion partners. RESULTS: Molecular karyotyping showed the translocation and amplification of regions of chromosomes 20q13 and 22q12. Cloning of the breakpoint showed an in-frame fusion between the EWSR1 and NFATc2 genes, resulting in loss of the NH(2)-terminal, calcineurin-dependent control region and an intact active domain of NFATc2 controlled by the transactivation domains of EWSR1. CONCLUSION: A new translocation involving EWSRI and NFATc2 was cloned. NFATc2 is a transcription factor that is not a member of the ETS family and functions in T-cell differentiation and immune response. Direct involvement of NFATc2 has not yet been observed in oncogenesis. We show that due to the shared sequence recognition of NFATc2 and the ETS family, shared transcriptional control is possible using activating protein complex 1.


Assuntos
Neoplasias Ósseas/genética , Fatores de Transcrição NFATC/genética , Proteínas de Fusão Oncogênica/genética , Sarcoma de Ewing/genética , Translocação Genética , Adolescente , Adulto , Neoplasias Ósseas/patologia , Proteínas de Ligação a Calmodulina/genética , Clonagem Molecular , Hibridização Genômica Comparativa , Humanos , Hibridização in Situ Fluorescente , Interfase/genética , Masculino , Fatores de Transcrição NFATC/fisiologia , Proteínas de Fusão Oncogênica/química , Proteína EWS de Ligação a RNA , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma de Ewing/patologia , Análise de Sequência de DNA , Análise de Sequência de Proteína , Adulto Jovem
14.
Blood ; 113(12): 2715-22, 2009 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-19096014

RESUMO

Clinical responses of solid tumors after allogeneic human leukocyte antigen-matched stem cell transplantation (SCT) often coincide with severe graft-versus-host disease (GVHD). Targeting minor histocompatibility antigens (mHags) with hematopoiesis- and cancer-restricted expression, for example, HA-1, may allow boosting the antitumor effect of allogeneic SCT without risking severe GVHD. The mHag HA-1 is aberrantly expressed in cancers of most entities. However, an estimated 30% to 40% of solid tumors do not express HA-1 (ie, are HA-1(neg)) and cannot be targeted by HA-1-specific immunotherapy. Here, we investigated the transcriptional regulation of HA-1 gene expression in cancer. We found that DNA hypermethylation in the HA-1 promoter region is closely associated with the absence of HA-1 gene expression in solid tumor cell lines. Moreover, we detected HA-1 promoter hypermethylation in primary cancers. The hypomethylating agent 5-aza-2'-deoxycytidine induced HA-1 expression only in HA-1(neg) tumor cells and sensitized them for recognition by HA-1-specific cytotoxic T lymphocytes. Contrarily, the histone deacetylation inhibitor trichostatin A induced HA-1 expression both in some HA-1(neg) tumor cell lines and in normal nonhematopoietic cells. Our data suggest that promoter hypermethylation contributes to the HA-1 gene regulation in tumors. Hypomethylating drugs might extend the safe applicability of HA-1 as an immunotherapeutic target on solid tumors after allogeneic SCT.


Assuntos
Antígenos de Neoplasias/biossíntese , Azacitidina/análogos & derivados , Metilação de DNA/efeitos dos fármacos , DNA de Neoplasias/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Imunoterapia/métodos , Antígenos de Histocompatibilidade Menor/biossíntese , Neoplasias/genética , Oligopeptídeos/biossíntese , Acetilação/efeitos dos fármacos , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/metabolismo , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , Decitabina , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/imunologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias/imunologia , Neoplasias/patologia , Oligopeptídeos/genética , Oligopeptídeos/imunologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Linfócitos T Citotóxicos/imunologia , Transcrição Gênica
15.
Differentiation ; 76(1): 83-90, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18021258

RESUMO

The cell nucleus is highly organized with chromosomes occupying discrete, partially overlapping territories, and proteins that localize to specific nuclear compartments. This spatial organization of the nucleus is considered to be dynamic in response to environmental and cellular conditions to support changes in transcriptional programs. Chromatin, however, is relatively immobile when analyzed in living cells and shows a constrained Brownian type of movement. A possible explanation for this relative immobility is that chromatin interacts with a nuclear matrix structure and/or with nuclear compartments. Here, we explore the use of photoactivatable GFP fused to histone H4 as a potential tool to analyze the mobility of chromatin at various nuclear compartments. Selective photoactivation of photoactivatable-GFP at defined nuclear regions was achieved by two-photon excitation with 820 nm light. Nuclear speckles, which are considered storage sites of splicing factors, were visualized by coexpression of a fluorescent protein fused to splicing factor SF2/ASF. The results reveal a constrained chromatin motion, which is not affected by transcriptional inhibition, and suggests an intimate interaction of chromatin with speckles.


Assuntos
Cromatina/fisiologia , Proteínas de Fluorescência Verde/análise , Histonas/análise , Transporte Biológico/genética , Compartimento Celular , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Histonas/metabolismo , Humanos , Espaço Intranuclear/fisiologia , Espaço Intranuclear/ultraestrutura , Microscopia Confocal
16.
Clin Cancer Res ; 13(24): 7322-8, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18094413

RESUMO

PURPOSE: Angiomatoid fibrous histiocytoma (AFH) is a low-grade mesenchymal neoplasm which usually occurs in children and adolescents. Either FUS-ATF1 or EWSR1-ATF1 have been detected in the few cases published, pointing to the interchangeable role of FUS and EWSR1 in this entity. EWSR1-ATF1 also represents the most frequent genetic alteration in clear cell sarcoma, suggesting the existence of a molecular homology between these two histotypes. We investigated the presence of EWSR1-CREB1, recently found in gastrointestinal clear cell sarcoma, and FUS-CREB1, as well as the already reported FUS-ATF1 and EWSR1-ATF1 in a series of AFH. EXPERIMENTAL DESIGN: Fourteen cases were analyzed by fluorescence in situ hybridization (FISH) on paraffin-embedded tissue sections, using a commercial EWSR1 probe and custom-designed probes for FUS, ATF1, and CREB1. In two cases, four-color FISH was also done. Reverse transcription-PCR for the four hypothetical fusion genes was done in one case, for which frozen material was available. RESULTS: Thirteen cases showed rearrangements of both EWSR1 and CREB1, whereas one case showed the rearrangement of both EWSR1 and ATF1. Four-color FISH confirmed the results in two selected cases. Reverse transcription-PCR showed EWSR1-CREB1 transcript in the case analyzed. CONCLUSION: We identified the presence of either EWSR1-CREB1 or EWSR1-ATF1 in all the cases, strengthening the concept of chromosomal promiscuity between AFH and clear cell sarcoma. Either the occurrence of a second unknown tumor-specific molecular event or, perhaps more likely, divergent differentiation programs of the putatively distinct precursor cells of AFH and clear cell sarcoma might be invoked in order to explain the two different phenotypes.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Histiocitoma Fibroso Maligno/genética , Proteínas de Fusão Oncogênica/genética , Neoplasias de Tecidos Moles/genética , Fatores de Transcrição/genética , Adolescente , Adulto , Sequência de Bases , Criança , Pré-Escolar , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Cell Oncol ; 29(5): 387-98, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17726261

RESUMO

BACKGROUND: Tumor staging insufficiently discriminates between colon cancer patients with poor and better prognosis. We have evaluated, for the primary tumor, if the carcinoma-percentage (CP), as a derivative from the carcinoma-stromal ratio, can be applied as a candidate marker to identify patients for adjuvant therapy. METHODS: In a retrospective study of 63 patients with colon cancer (stage I-III, 1990-2001) the carcinoma-percentage of the primary tumor was estimated on routine H&E stained histological sections. Additionally these findings were validated in a second independent study of 59 patients (stage I-III, 1980-1992). (None of the patients had received preoperative chemo- or radiation therapy nor adjuvant chemotherapy.) RESULTS: Of 122 analyzed patients 33 (27.0%) had a low CP and 89 (73.0%) a high CP. The analysis of mean survival revealed: overall-survival (OS) 2.13 years, disease-free- survival (DFS) 1.51 years for CP-low and OS 7.36 years, DFS 6.89 years for CP-high. Five-year survival rates for CP-low versus CP-high were respectively for OS: 15.2% and 73.0% and for DFS: 12.1% and 67.4%. High levels of significance were found (OS p<0.0001, DFS p<0.0001) with hazard ratio's of 3.73 and 4.18. In a multivariate Cox regression analysis, CP remained an independent variable when adjusted for either stage or for tumor status and lymph-node status (OS p<0.001, OS p<0.001). CONCLUSIONS: The carcinoma-percentage in primary colon cancer is a factor to discriminate between patients with a poor and a better outcome of disease. This parameter is already available upon routine histological investigation and can, in addition to the TNM classification, be a candidate marker to further stratify into more individual risk groups.


Assuntos
Neoplasias do Colo/diagnóstico , Neoplasias do Colo/patologia , Linfonodos/patologia , Células Estromais/patologia , Idoso , Neoplasias do Colo/cirurgia , Neoplasias do Colo/terapia , Demografia , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Instabilidade de Microssatélites , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes
18.
Cancer Genet Cytogenet ; 176(2): 115-20, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17656253

RESUMO

Parosteal adipocytic tumors of the bone are extremely rare. As a result, (cyto-) genetic data on this entity are essentially lacking. In the literature there is debate as to whether these lesions should be classified according to the criteria used in soft-tissue tumor pathology, or if they should be considered a separate bone tumor entity. Here we present a 68-year-old male patient with a tumor in his right upper leg diagnosed as parosteal atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDLS) on the basis of clinico-radiologic and pathologic findings. Molecular cytogenetic investigations using combined binary ratio labeling fluorescence in situ hybridization and array comparative genomic hybridization showed abnormalities, which are in accordance with the histologic appearance of an atypical lipomatous tumor/well-differentiated liposarcoma. Therefore, on the basis of these molecular cytogenetic investigations, we conclude that parosteal liposarcoma is not a separate entity but should be categorized within the spectrum of soft-tissue ALT/WDLS.


Assuntos
Neoplasias Ósseas/diagnóstico , Hibridização in Situ Fluorescente , Lipoma/diagnóstico , Lipossarcoma/diagnóstico , Hibridização de Ácido Nucleico , Análise Serial de Tecidos/métodos , Idoso , Neoplasias Ósseas/genética , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 12 , Diagnóstico Diferencial , Progressão da Doença , Humanos , Hibridização in Situ Fluorescente/métodos , Lipoma/genética , Lipossarcoma/genética , Masculino , Hibridização de Ácido Nucleico/métodos , Periósteo
19.
Ann N Y Acad Sci ; 1098: 330-4, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17435139

RESUMO

Advances in genomics and proteomics increasingly contribute to the understanding of signal transduction pathways that control growth, differentiation, and death of cells. Since defects in these processes may result in the expression of inherited and or acquired disease, the identification of candidate disease genes and modifier genes by parallel use of genotyping together with an integrated study of gene expression and metabolite levels is instrumental for future health care. This approach, called systems biology, aims to recognize early onset of disease, institute preventive treatment, and identify new molecular targets for novel drugs in cancer, cardiovascular and metabolomic disease (e.g., diabetes), and neurodegenerative disorders. Gene interaction networks have recently been demonstrated, in which hub genes, that is, genes that show the highest level of interactions with other genes, play a special role. Hub genes, often chromatin regulators, may act as modifier genes (genes that modify the effect of other genes) in multiple mechanistically unrelated genetic diseases in humans. In addition, it has been shown that small metabolites such as hormones and cytokines, or proteins/enzymes such as C reactive protein (C-RP) and matrix metaloproteinase (MMP), reflect disease status in case of oral cancer, asthma, or periodontal and cardiac disease. Many of these molecular targets, as well as pathogen-specific DNA and RNA sequences, can be measured in oral fluids, providing a unique opportunity to develop novel noninvasive diagnostic tests. Efforts so far concentrate on the use of lab-on-a-chip technology in combination with novel reporters and microsensor arrays to measure multianalytes in oral fluids. Handheld devices that perform sensitive detection of multiple analytes in oral fluid will be obtainable in the near future.


Assuntos
Genômica , Doenças da Boca/diagnóstico , Doenças da Boca/genética , Proteômica , Diagnóstico Bucal , Genômica/métodos , Humanos , Doenças da Boca/metabolismo , Doenças da Boca/patologia , Proteômica/métodos
20.
Ann N Y Acad Sci ; 1098: 437-45, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17435148

RESUMO

A novel assay is described for multiplex detection of antibodies against different pathogens from a single sample. The assay employs a modified lateral flow format (consecutive flow, CF) together with a sensitive reporter particle technology (up-converting phosphor technology, UPT) that allows for fully instrumented assay analysis. Lateral flow (LF) strips developed for the detection of human antibodies against human immunodeficiency virus type-1 and -2 (HIV-1 and -2) with additional capture zones to detect antibodies against Myobacterium tuberculosis (TB) and hepatitis C Virus (HCV) provided the strips to test multiplexing. Data are presented that show the performance of the TB and HCV test, as well as two multiplex assays, TB with HIV and HCV with HIV. The TB/HCV assays demonstrate excellent detection capability, and HIV multiplexing does not affect the qualitative test result. The bench-top CF format was converted to a microfluidic platform and a first prototype semiautomated chip capable of performing CF is presented here.


Assuntos
Anticorpos Antibacterianos/sangue , Anticorpos Anti-HIV/sangue , HIV/imunologia , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Mycobacterium tuberculosis/imunologia , Anticorpos Antibacterianos/biossíntese , Anticorpos Anti-HIV/biossíntese , Anticorpos Anti-Hepatite C/biossíntese , Humanos , Microfluídica/instrumentação
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