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1.
Stem Cell Reports ; 17(4): 775-788, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35334217

RESUMO

The generation of retinal organoids from human pluripotent stem cells (hPSC) is now a well-established process that in part recapitulates retinal development. However, hPSC-derived photoreceptors that exhibit well-organized outer segment structures have yet to be observed. To facilitate improved inherited retinal disease modeling, we determined conditions that would support outer segment development in maturing hPSC-derived photoreceptors. We established that the use of antioxidants and BSA-bound fatty acids promotes the formation of membranous outer segment-like structures. Using new protocols for hPSC-derived retinal organoid culture, we demonstrated improved outer segment formation for both rod and cone photoreceptors, including organized stacked discs. Using these enhanced conditions to generate iPSC-derived retinal organoids from patients with X-linked retinitis pigmentosa, we established robust cellular phenotypes that could be ameliorated following adeno-associated viral vector-mediated gene augmentation. These findings should aid both disease modeling and the development of therapeutic approaches for the treatment of photoreceptor disorders.


Assuntos
Organoides , Células-Tronco Pluripotentes , Antioxidantes/farmacologia , Suplementos Nutricionais , Humanos , Lipídeos , Retina , Células Fotorreceptoras Retinianas Cones
2.
Clin Transl Gastroenterol ; 11(3): e00139, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32352723

RESUMO

INTRODUCTION: The burden of hepatocellular carcinoma (HCC) occurring in patients with alcoholic liver disease (ALD) is increasing at an alarming rate. The aims of this study were to compare the patient and tumor characteristics of HCC occurring in ALD-alone relative to and in addition to other chronic liver diseases. METHODS: Patients diagnosed with HCC between 2000 and 2014 were identified at 5 US clinical centers. The patients were categorized as ALD-alone, ALD plus viral hepatitis, or a non-ALD etiology. Clinical and tumor characteristics among the 3 groups were compared, and survival probability was estimated by the Kaplan-Meier method. The frequency of noncirrhotic HCC was compared across the 3 groups. RESULTS: A total of 5,327 patients with HCC were analyzed. Six hundred seventy (12.6%) developed HCC due to underlying ALD. Ninety-one percent of ALD-related HCC arose in men, in contrast to non-ALD etiologies where men accounted for 70% of HCCs cases (P < 0.001). Patients with ALD-alone-related HCC were older at diagnosis and had tumors less likely to be detected as part of routine surveillance. The ALD-alone cohort was least likely to be within the Milan criteria and to undergo liver transplantation. Overall survival in the ALD-alone HCC cohort was lower than the other 2 groups (1.07 vs 1.31 vs 1.41 years, P < 0.001). HCC in the noncirrhotic ALD cohorts occurred in only 3.5% of the patients compared with 15.7% in patients with non-ALD etiologies (P < 0.001). DISCUSSION: HCC occurring in patients with ALD occurred mostly in older men and almost exclusively in a cirrhotic background. They present with advanced tumors, and their survival is lower than HCCs occurring in non-ALD.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Hepatopatias Alcoólicas/patologia , Neoplasias Hepáticas/epidemiologia , Fígado/patologia , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Progressão da Doença , Feminino , Humanos , Hepatopatias Alcoólicas/mortalidade , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Estados Unidos/epidemiologia
3.
Stem Cell Res Ther ; 9(1): 156, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29895313

RESUMO

BACKGROUND: The use of human pluripotent stem cell-derived retinal cells for cell therapy strategies and disease modelling relies on the ability to obtain healthy and organised retinal tissue in sufficient quantities. Generating such tissue is a lengthy process, often taking over 6 months of cell culture, and current approaches do not always generate large quantities of the major retinal cell types required. METHODS: We adapted our previously described differentiation protocol to investigate the use of stirred-tank bioreactors. We used immunohistochemistry, flow cytometry and electron microscopy to characterise retinal organoids grown in standard and bioreactor culture conditions. RESULTS: Our analysis revealed that the use of bioreactors results in improved laminar stratification as well as an increase in the yield of photoreceptor cells bearing cilia and nascent outer-segment-like structures. CONCLUSIONS: Bioreactors represent a promising platform for scaling up the manufacture of retinal cells for use in disease modelling, drug screening and cell transplantation studies.


Assuntos
Reatores Biológicos/normas , Organoides/metabolismo , Células Fotorreceptoras/metabolismo , Células-Tronco Pluripotentes/metabolismo , Retina/metabolismo , Humanos
4.
Hum Gene Ther ; 29(10): 1124-1139, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29580100

RESUMO

Adeno-associated viral vectors are showing great promise as gene therapy vectors for a wide range of retinal disorders. To date, evaluation of therapeutic approaches has depended almost exclusively on the use of animal models. With recent advances in human stem cell technology, stem cell-derived retina now offers the possibility to assess efficacy in human organoids in vitro. Here we test six adeno-associated virus (AAV) serotypes [AAV2/2, AAV2/9, AAV2/8, AAV2/8T(Y733F), AAV2/5, and ShH10] to determine their efficiency in transducing mouse and human pluripotent stem cell-derived retinal pigment epithelium (RPE) and photoreceptor cells in vitro. All the serotypes tested were capable of transducing RPE and photoreceptor cells in vitro. AAV ShH10 and AAV2/5 are the most efficient vectors at transducing both mouse and human RPE, while AAV2/8 and ShH10 achieved similarly robust transduction of human embryonic stem cell-derived cone photoreceptors. Furthermore, we show that human embryonic stem cell-derived photoreceptors can be used to establish promoter specificity in human cells in vitro. The results of this study will aid capsid selection and vector design for preclinical evaluation of gene therapy approaches, such as gene editing, that require the use of human cells and tissues.


Assuntos
Dependovirus/fisiologia , Vetores Genéticos/genética , Células Fotorreceptoras/citologia , Células Fotorreceptoras/metabolismo , Células-Tronco Pluripotentes/citologia , Epitélio Pigmentado da Retina/citologia , Tropismo Viral , Animais , Diferenciação Celular , Células Cultivadas , Dependovirus/classificação , Imunofluorescência , Expressão Gênica , Técnicas de Transferência de Genes , Genes Reporter , Humanos , Camundongos , Especificidade de Órgãos/genética , Regiões Promotoras Genéticas , Transdução Genética , Transgenes
5.
Am J Surg Pathol ; 34(6): 767-76, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20421783

RESUMO

The importance of HER2 status in breast cancer management has focused attention on the ability of clinical assays to correctly assign HER2 amplification status. There is no consensus as to the best method for assessing HER2 status. Disadvantages of fluorescence in situ hybridization (FISH) testing include longer time required for staining and scoring slides, requirements for specialized training and fluorescence microscopy, and loss of the signal due to quenching of the fluorescent dye. Silver-enhanced in situ hybridization (SISH) is a rapid fully automated assay providing permanently stained slides that are interpreted by conventional bright field microscopy which enables pathologists to evaluate slides within the context of tissue morphology. This study evaluates the concordance between SISH and FISH assays in determining the status of HER2 gene amplification in a cohort of 298 primary invasive breast carcinomas. Furthermore, we assessed in detail the variables contributing to interobserver interpretive reproducibility of HER2 SISH among 10 pathologists. HER2 was quantified using the ratio of HER2 to CHR17 signals using the conventional historical interpretation scale and also by the American Society of Clinical Oncology/College of American Pathologists reporting scheme. For SISH status determined by consensus among 10 pathologists, overall concordance between SISH and FISH was identified in 288 of 298 cases (96.6%) using the conventional Food and Drug Administration approved criteria. Overall agreement was observed in 282 of 285 cases (98.9%) using the American Society of Clinical Oncology/College of American Pathologists result reporting scheme (with equivocal cases removed). In conclusion, SISH represents a novel approach for the determination of HER2 status in breast cancer. The overall concordance between SISH and FISH is excellent, and the interpretation of SISH results by pathologists is most reproducible using the HER2/CHR17 ratio.


Assuntos
Neoplasias da Mama/genética , Genes erbB-2 , Hibridização In Situ/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Compostos de Prata , Feminino , Humanos , Hibridização in Situ Fluorescente , Variações Dependentes do Observador , Reprodutibilidade dos Testes
8.
Hum Pathol ; 38(8): 1145-59, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17640553

RESUMO

Metallographic methods, in which a target is visualized using a probe or antibody that deposits metal selectively at its binding site, offers many advantages for bright-field in situ hybridization (ISH) detection as well as for other labeling and detection methods. Autometallographically enhanced gold labeling procedures have demonstrated higher sensitivity than conventional enzyme chromogens. Enzyme metallography, a novel procedure in which an enzymatic probe is used to deposit metal directly from solution, has been used to develop bright-field ISH methods for HER2 gene determination in breast cancer and other biopsy specimens. It provides the highest level of sensitivity and resolution, both for visualizing endogenous gene copies in nonamplified tissues and for resolving multiple gene copies to allow copy enumeration in amplified tissues without the need for oil immersion or fluorescence optics. An automated enzyme metallography procedure, silver ISH, has been developed for use in slide-staining instruments. Metallographic staining also provides excellent results for immunohistochemistry and may be combined with other staining procedures for the simultaneous detection of more than one gene or combinations of genes and proteins.


Assuntos
Coloide de Ouro/química , Hibridização In Situ/métodos , Ácidos Nucleicos/química , Compostos de Prata/química , Coloração pela Prata/métodos , Adenocarcinoma/química , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Neoplasias da Mama/química , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Enzimas/química , Feminino , Coloide de Ouro/imunologia , Humanos , Receptor ErbB-2/análise , Receptor ErbB-2/genética , Compostos de Prata/imunologia
9.
Appl Immunohistochem Mol Morphol ; 15(1): 94-102, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17536315

RESUMO

The 2 methodologies in current clinical use to assess HER2 status in breast cancer are: fluorescence in situ hybridization (FISH) (gene amplification) and immunohistochemistry (protein over-expression). A consistent finding has been that 3% to 15% of breast cancers over-express HER2 protein without evidence for gene amplification. Accurate determination of the HER2 status has implications for selecting patients most likely to respond to trastuzumab. We report here our preliminary experience with a new anti-HER2 rabbit monoclonal antibody, 4B5. The evaluation of HER2 status in 2 different cohorts of breast cancer cases (Single Institution (SI) and Multinational (MN)) with a total of 322 breast cancer cases was performed on an automated staining system (Ventana Medical Systems, Inc, Tucson, AZ) and scored by 3 pathologists (0-3+), for comparison with CB11 staining results (PATHWAY) and FISH (PathVysion). Interlaboratory reproducibility of automated staining results and interpretation was determined on a subset of the SI cohort at 3 separate laboratories. Rabbit monoclonal 4B5 demonstrated sharper membrane staining with less cytoplasmic and stromal background staining than CB11. In the SI cohort, the staining results for 4B5 were highly comparable with those obtained for CB11 with an overall concordance of 93.3%. In the multinational cohort, the overall concordance with CB11 was 84.7%. This lower level of concordance was associated with a much higher overall agreement of 4B5 with FISH (89.5%), compared with agreement of CB11 with FISH (81.2%). The difference in the performance of CB11 in the MN cohort versus the SI cohort may be due to differences in tissue fixation and processing in a centralized, high volume laboratory in an academic medical center versus multiple sites in the international community with potentially nonstandardized techniques. The staining results with 4B5 indicate that it has a more robust performance than CB11 because the correlation of 4B5 with FISH was nearly equivalent (88.2% MN; 89.3% SI) in both cohorts. Interlaboratory reproducibility was also excellent (kappa 1.0). RMoAb 4B5 provides excellent sensitivity, specificity, and interlaboratory reproducibility for the detection of HER2 status in breast cancer.


Assuntos
Anticorpos Monoclonais/biossíntese , Neoplasias da Mama/diagnóstico , Receptor ErbB-2/análise , Animais , Corantes , Feminino , Humanos , Imuno-Histoquímica/métodos , Imuno-Histoquímica/normas , Hibridização in Situ Fluorescente/normas , Métodos , Coelhos , Receptor ErbB-2/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
J Mol Histol ; 38(2): 129-34, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17205377

RESUMO

Molecular morphologic tools exist for simultaneously visualizing immunophenotype and genotype of tumors, but are frequently hampered by a delicate balance between removing sufficient amount of the protein blocking full access of the probe to hybridize to target nucleic acids while still preserving sufficient target antigen for immunophenotyping. The result is often suboptimal, with either insufficiently visualized gene deletions and amplifications due to masking protein, or overdigestion of the protein target. Our purpose was to design and validate a gated genotyping assay that enables optimal and concomitant detection of both gene and protein. Using the proliferating endothelial cell compartment within gliomas organized in a tissue microarray (TMA), we tested the hypothesis that tyramide signal amplification (TSA) with deposition of a fluorochrome could be used during immunophenotyping, permitting sufficient protein digestion while insuring probe accessibility to nucleic acid target. The method was successfully validated using a TMA containing 38 glioma cases previously genotyped for EGFR amplification. CD31 positive endothelial cells were segregated via TSA-based Alexa-Fluor 647 immunofluorescence for analysis of EGFR amplification of the gliomas organized in the TMA. Enhanced immunoFISH (TSA) successfully segregates immunophenotypically-defined cell populations for gated genotyping.


Assuntos
Imuno-Histoquímica/métodos , Imunofenotipagem/métodos , Hibridização in Situ Fluorescente/métodos , Neoplasias/genética , Neoplasias/patologia , Tiramina , Receptores ErbB/metabolismo , Genótipo , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo , Fenótipo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo
11.
J Mol Histol ; 38(2): 159-65, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17094016

RESUMO

Implementation of interphase fluorescence in situ hybridization (FISH) assays in the clinical laboratory requires validation against established methods. Validation tools in common use include exchange of consecutive sections with another institution that has already established the FISH assay, comparison with conventional banded metaphase cytogenetics, confirmation of specificity using probed normal metaphases, consecutive paraffin sections of a validation set tested by a reference laboratory, and specificity assessment against well characterized cell lines. We have investigated the feasibility of using tissue microarrays (TMA) constructed from murine xenografts as a preliminary specificity-screening tool for validation of interphase FISH assays. Cell lines currently in use for FISH controls are used to generate xenografts in SCID mice which are fixed in formalin and paraffin embedded. A TMA is constructed using duplicate donor cores from the xenograft blocks. Xenografts used represent a wide range of translocations used routinely for formalin fixed paraffin embedded sections evaluated by FISH. Probe cocktails (Abbott-Vysis), for several non-random translocations associated with hematologic neoplasms and soft tissue sarcomas have been used in this manner. On-line deparaffinization, cell conditioning, and prehybridization steps are automated using a staining workstation (Ventana Discovery XT); hybridization and stringency washes are performed manually offline. FISH-probed TMAs are tracked using a Metasystems image scanner and analyzed using classifiers specifically developed for each molecular abnormality. FISH results for each xenograft in the TMA correspond exactly to the genotype previously established for the parent cell line from which the xenograft was prepared. Moderate complexity tissue microarrays constructed from murine xenografts are excellent validation tools for initial assessment of interphase FISH probe specificity.


Assuntos
Sondas de DNA/genética , Formaldeído , Hibridização in Situ Fluorescente/métodos , Inclusão em Parafina/métodos , Análise Serial de Tecidos/métodos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Neoplasias/genética
12.
Arch Pathol Lab Med ; 130(10): 1440-5, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17090184

RESUMO

CONTEXT: Correct assessment of human epidermal growth factor receptor 2 (HER2) status is essential in managing patients with invasive breast carcinoma, but few data are available on the accuracy of laboratories performing HER2 testing by immunohistochemistry (IHC). OBJECTIVE: To review the results of the 2004 and 2005 College of American Pathologists HER2 Immunohistochemistry Tissue Microarray Survey. DESIGN: The HER2 survey is designed for laboratories performing immunohistochemical staining and interpretation for HER2. The survey uses tissue microarrays, each consisting of ten 3-mm tissue cores obtained from different invasive breast carcinomas. All cases are also analyzed by fluorescence in situ hybridization. Participants receive 8 tissue microarrays (80 cases) with instructions to perform immunostaining for HER2 using the laboratory's standard procedures. The laboratory interprets the stained slides and returns results to the College of American Pathologists for analysis. In 2004 and 2005, a core was considered "graded" when at least 90% of laboratories agreed on the result--negative (0, 1+) versus positive (2+, 3+). This interlaboratory comparison survey included 102 laboratories in 2004 and 141 laboratories in 2005. RESULTS: Of the 160 cases in both surveys, 111 (69%) achieved 90% consensus (graded). All 43 graded cores scored as IHC-positive were fluorescence in situ hybridization-positive, whereas all but 3 of the 68 IHC-negative graded cores were fluorescence in situ hybridization-negative. Ninety-seven (95%) of 102 laboratories in 2004 and 129 (91%) of 141 laboratories in 2005 correctly scored at least 90% of the graded cores. CONCLUSION: Performance among laboratories performing HER2 IHC in this tissue microarray-based survey was excellent. Cores found to be IHC-positive or IHC-negative by participant consensus can be used as validated benchmarks for interlaboratory comparison, allowing laboratories to assess their performance and determine if improvements are needed.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma/metabolismo , Carcinoma/patologia , Imuno-Histoquímica/métodos , Laboratórios/normas , Receptor ErbB-2/análise , Coleta de Dados , Feminino , Genes erbB-2 , Humanos , Hibridização in Situ Fluorescente , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Reprodutibilidade dos Testes , Coloração e Rotulagem
13.
Appl Immunohistochem Mol Morphol ; 14(4): 436-40, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17122642

RESUMO

Determination of HER2 status by fluorescence in situ hybridization (FISH) in breast carcinoma correlates well with response to targeted therapy and prognosis. However, manual time consuming methods and quantification aspects of the procedure may be challenging for some laboratories. We examined the feasibility of automating these components of the FISH assay using a tissue microarray (TMA-118 clinically annotated cases) and a series of 41 whole sections. An in situ hybridization automated staining workstation was used to automate a programmed overnight start, on line baking, deparaffinization, cell conditioning, protease digestion, and prehybridization buffer washing. Dual label probe/target codenaturation/hybridization and stringency washing were done off line. The HER2 and CEP17 spot counts were quantified, and the HER2/CEP17 ratio calculated, via an imaging workstation. Results were benchmarked against manual counts for whole sections, and bright field in situ hybridization [silver in situ hybridization (SISH)] for the TMA. Automated FISH results using whole sections correlated well with manual results: HER2/CEP17 ratio correlation coefficient r = 0.9154, r = 0.8380, P < 0.0001. Correlation between automated and manual TMA FISH results was also excellent, and disease-free survival was significantly shorter (P < 0.001) for the HER2 amplified cases. Automation of the laborious manual prehybridization and image quantification components of FISH using directly labeled probes is feasible. Operational gains and enhanced consistency are inherent in this automated approach to HER2 clinical FISH testing.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Amplificação de Genes , Genes erbB-2 , Automação , Estudos de Viabilidade , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Processamento de Sinais Assistido por Computador , Análise Serial de Tecidos
14.
Arch Pathol Lab Med ; 130(6): 779-82, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16740027

RESUMO

CONTEXT: We have developed tissue microarray-based surveys to allow laboratories to compare their performance in staining predictive immunohistochemical markers, including proto-oncogene CD117 (c-kit), which is characteristically expressed in gastrointestinal stromal tumors (GISTs). GISTs exhibit activating mutations in the c-kit proto-oncogene, which render them amenable to treatment with imatinib mesylate. Consequently, correct identification of c-Kit expression is important for the diagnosis and treatment of GISTs. OBJECTIVE: To analyze CD117 immunohistochemical staining performance by a large number of clinical laboratories. DESIGN: A mechanical device was used to construct tissue microarrays consisting of 3 x 1-mm cores of 10 tumor samples, which can be used to generate hundreds of tissue sections from the arrayed cases, suitable for large-scale interlaboratory comparison of immunohistochemical staining. RESULTS: An initial survey of 63 laboratories and a second survey of 90 laboratories, performed in 2004 and 2005, exhibited >81% concordance for 7 of 10 cores, including all 4 GIST cases, which were immunoreactive for CD117 with >95% staining concordance. Three of the cores achieved less than 81% concordance of results, possibly due to the presence of foci of necrosis in one core and CD117-positive mast cells in 2 cores of CD117-negative neoplasms. CONCLUSIONS: There was good performance among a large number of laboratories performing CD117 immunohistochemical staining, with consistently higher concordance of results for CD117-positive GIST cases than for nonimmunoreactive cases. Tissue microarrays for CD117 and other predictive markers should be useful for interlaboratory comparisons, quality assurance, and education of participants regarding staining nuances such as the expression of CKIT by nonneoplastic mast cells.


Assuntos
Coleta de Dados , Imuno-Histoquímica/normas , Laboratórios/normas , Proteínas Proto-Oncogênicas c-kit/metabolismo , Garantia da Qualidade dos Cuidados de Saúde , Análise Serial de Tecidos/normas , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Técnicas de Laboratório Clínico/normas , Neoplasias Gastrointestinais/química , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/metabolismo , Humanos , América do Norte , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-kit/análise , Sociedades Médicas , Análise Serial de Tecidos/métodos
15.
Appl Immunohistochem Mol Morphol ; 13(4): 371-5, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16280669

RESUMO

Ultrasensitive bright field in situ hybridization assays using enzyme metallography (EnzMet) have been developed and validated, but little is known regarding the applicability of EnzMet for immunophenotypic detection of protein via IHC. Superior resolution via discrete metallographic deposits offers the potential for enhancing high-resolution immunophenotyping. Using high-complexity tissue microarrays (TMAs), 88 common solid tumors were evaluated by automated EnzMet (Nanoprobes and Ventana). Targets were chosen to assess the ability of EnzMet to specifically localize encoded antigens in the nucleus (estrogen receptor), cytoplasm (cytokeratins), and cytoplasmic membrane (HER2) in TMAs. Results were compared with conventional IHC diaminobenzidine (DAB) immunostaining. There was full concordance between the EnzMet and conventional IHC results. Furthermore, the EnzMet reaction products did not appreciably diffuse, were dense and sharply defined, and provided excellent high-resolution differentiation of cellular compartments in paraffin sections for the nuclear, cytoplasmic, and cell membrane-localized antigens evaluated. The higher density of elemental silver deposited during enzyme metallography permitted evaluation of core immunophenotypes at a relatively low magnification, allowing more tissue to be screened in an efficient manner. This preliminary study shows the utility of using enzyme metallography for high-resolution immunophenotyping in TMAs.


Assuntos
Carcinoma/patologia , Compartimento Celular , Estruturas Celulares/patologia , Imunofenotipagem/métodos , Neoplasias/patologia , Análise Serial de Tecidos , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Carcinoma/imunologia , Compartimento Celular/imunologia , Estruturas Celulares/imunologia , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Feminino , Humanos , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Masculino , Sondas Moleculares/imunologia , Neoplasias/imunologia , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Prata/imunologia
16.
Am J Surg Pathol ; 29(11): 1505-11, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16224218

RESUMO

Fluorescence in situ hybridization (FISH) has both excellent sensitivity and specificity in detecting HER2 gene amplification in invasive breast carcinoma. FISH has not been widely implemented in clinical practice because of reagent costs and the special instrumentation and expertise required to perform and integrate the assay. Immunohistochemistry (IHC) for HER2 protein is widely used, but false-positive and false-negative results are problematic. We developed a bright-field assay to visualize HER2 gene amplification and concomitant HER2 protein expression (EnzMet GenePro). This assay detects HER2 gene amplification via deposition of metallic silver by enzyme metallographytrade mark (EnzMettrade mark, Nanoprobes, Yaphank, NY) combined with HER2 protein detection by IHC using alkaline phosphatase and fast red K substrate visualization (CB11;Ventana, Tucson, AZ). The assay was performed on 94 invasive breast carcinomas, for which FISH (PathVysiontrade mark, Vysis, Downer's Grove, IL), conventional IHC (CB11), and enzyme metallography (EnzMettrade mark) results were known. The EnzMettrade mark component of the assay was scored as either HER2 gene amplified, polysomic, or nonamplified. The IHC component was scored using the conventional FDA scale of 0 to 3+. Concordance of the EnzMet component of the assay versus FISH was assessed and showed an excellent correlation (Pearson coefficient of 0.95; P < 0.001). The combination of gene and protein detection (EnzMet GenePro) displayed a specificity of 100% and an accuracy of 92.6% (95% confidence interval 85.3-97.0), facilitated recognition of gene/protein discordances, and allowed for efficient interpretation of the slide by conventional light microscopy. The interobserver kappa for each component was excellent (IHC, kappa = 0.94; and EnzMettrade mark, kappa = 0.96). EnzMet is the first bright-field ISH assay in our experience that routinely and nonambiguously detects endogenous HER2 signals, essential for a reliable clinical HER2 assay, and in combination with HER2 protein enables improved diagnosis in borderline cases.


Assuntos
Adenocarcinoma/genética , Neoplasias da Mama/genética , Genes erbB-2/imunologia , Imuno-Histoquímica/métodos , Receptor ErbB-2/imunologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/imunologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/imunologia , Feminino , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes
17.
Am J Surg Pathol ; 29(9): 1221-7, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16096413

RESUMO

Breast carcinomas with amplification of HER2 on chromosome 17 are associated with HER2 protein overexpression, adversely affecting prognosis and predicting response to Herceptin therapy. Chromosome 17 polysomy is encountered in assessing HER2 gene status, and its impact on HER2 gene and protein expression remains unclear. This impact was investigated in breast carcinomas identified by fluorescence in situ hybridization (FISH) to have a gain of chromosome 17 (CEP17+; n = 56), using a dual probe assay, which detects HER2 gene copy number and enumerates chromosome 17 (HER2/CEP17; Vysis). Cases were immunostained for HER2 protein (CB-11, Ventana), and scored blinded to FISH. A subgroup was evaluated by isotopic in situ hybridization for HER2 mRNA expression. Controls included ten HER2 amplified and ten nonamplified tumors, eusomic for chromosome 17. Immunohistochemistry (IHC) for HER2 protein was negative (0 or 1+) in 69% (39 of 56), 2+ in 27% (15 of 56), and 3+ in 3% (2 of 56) of CEP17+ cases. The mean CEP17 copy number among the three groups was similar (3.1, 3.0, and 3.1 for IHC 0/1+, 2+, and 3+, respectively). Isotopic in situ hybridization for HER2 mRNA performed on 26 CEP17+ cases (16 IHC 0-1+, 10 IHC 2+ or 3+) showed no increased HER2 mRNA expression (normalized to beta-actin mRNA). The mRNA expression and the IHC staining of the HER2-amplified and nonamplified controls was concordant with their FISH status. These results suggest that chromosome 17 polysomy in the absence of HER2 amplification does not have a significant biologic influence on HER2 gene expression in breast carcinoma.


Assuntos
Adenocarcinoma/genética , Neoplasias da Mama/genética , Cromossomos Humanos Par 17/genética , Genes erbB-2/fisiologia , Feminino , Dosagem de Genes , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , RNA Mensageiro/análise
18.
Clin Cancer Res ; 11(10): 3722-32, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15897569

RESUMO

PURPOSE: We examined the feasibility of using molecular characterization of circulating tumor cells as a method for early detection of breast cancer. RESEARCH DESIGN: Women without a prior history of cancer who had a breast abnormality detected on imaging followed by a breast biopsy were enrolled in this study. Density gradient centrifugation and immunomagnetic capture were used to enrich for epithelial cells from approximately 20 mL of blood. Real-time reverse transcription-PCR was used to quantitate the expression levels of the highly breast-specific genes, mammaglobin, gamma-aminobutyric acid type A receptor pi subunit (GABA A(pi)), B305D-C, and B726P in the epithelial cell-enriched samples. RESULTS: The assay was technically feasible in 154 of 199 accrued patients. From their clinical assessment, 100 patients had benign breast disease, 10 patients had ductal carcinoma in situ, and 44 patients had invasive breast cancer. We constructed a diagnostic test that classified patients with mammaglobin levels of at least 32.2 copies/pg beta-actin (units) in their circulating epithelial cells as positive for invasive breast cancer. This resulted in a sensitivity and specificity of 63.3% and 75.0%, respectively. A diagnostic test that classified patients as positive for invasive breast cancer when either mammaglobin levels were >46.3 units or B305D-C levels were >11.6 units increased the sensitivity and specificity to 70.5% and 81.0%, respectively. In the latter test, 12 of the 14 node-positive breast cancer patients were correctly identified. Including GABA A(pi) and B726P in the test did not increase its diagnostic potential. CONCLUSIONS: These results suggest that molecular characterization of circulating epithelial cells using mammaglobin and B305D-C offers potential for early detection of invasive breast cancer.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Perfilação da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Células Neoplásicas Circulantes , Uteroglobina/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Diagnóstico Diferencial , Feminino , Humanos , Mamoglobina A , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Uteroglobina/genética
19.
Gynecol Oncol ; 96(3): 594-600, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15721399

RESUMO

OBJECTIVE: To determine whether histologic or molecular markers assessed in pretreatment curettage specimens predict nodal metastasis in endometrial cancer. METHODS: Phenotypic and molecular variables (ploidy, proliferating cell nuclear antigen, MIB-1, p53, HER-2/neu, and bcl-2) were analyzed in preoperative specimens from 82 patients with endometrial cancer who had lymph nodes dissected. These 82 patients had been selected from a total population of 283 patients with endometrial cancer, using a case-cohort design. Weighted logistic regressions were then used to determine significant predictors of positive lymph nodes, and results were estimated for the total population of 283 patients. RESULTS: Of the overall population, 12% of patients were estimated to have positive lymph nodes. Histologic subtype, p53, and bcl-2 each were significantly correlated (P <0.05) with lymph node status. With application of stepwise logistic regression, p53 was the only independent predictor of lymph node status. In addition, a statistical model predictive of positive lymph nodes was generated which incorporated the risk factors p53, bcl-2, and histologic subtype. CONCLUSION: In pretreatment curettage specimens, the presence of unfavorable levels of p53 or bcl-2 or of nonendometrioid histologic features, or combinations of those, significantly predicted lymph node status, thus facilitating the preoperative identification of patients at risk of lymph node metastases.


Assuntos
Curetagem/métodos , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Linfonodos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ciclo Celular/fisiologia , Estudos de Coortes , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Ploidias , Valor Preditivo dos Testes
20.
Breast Cancer Res Treat ; 86(1): 75-88, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15218362

RESUMO

TGF beta/Smad signaling pathway members are potent tumor suppressors for many types of cancers. We hypothesize that breast tumors differentially express these genes and that this expression pattern plays a role in the proliferation of breast cancer. We examined the mRNA levels of TIEG, Smad7, Smad2, and Bard1 using real-time RT/PCR in 14 normal breast, five non-invasive, 57 invasive (including 29 with outcome data), and five metastatic breast tumor tissues. TIEG and Smad7 mRNA levels were lower in non-invasive tumors compared to normal breast tissues. TIEG, Bard1, and Smad2 mRNA levels were lower in invasive cancers compared to normal breast tissues. In addition, TIEG, Smad2, and Bard1, provided discriminatory ability to potentially distinguish between normal and tumor samples, N- and N+ tumors, and N-/good (no recurrence for at least 5 years) and N-/bad (recurrence within 3 years) outcome patients. TIEG mRNA levels accurately discriminated between normal breast tissue and primary tumors with a sensitivity and specificity of 96 and 93%, respectively. TIEG, in combination with Smad2, distinguished between N+ and N- primary tumors with a sensitivity and specificity of 75 and 85%, respectively. TIEG in combination with Bard1 discriminated between N-/bad outcome from N-/good tumors with a sensitivity and specificity of 83 and 82%, respectively. Our results support the hypothesis that the differential gene expression of TIEG, Smad2, and Bard1, which are tumor suppressor genes, plays a significant role in the proliferation of breast cancer. Further investigation is necessary to validate the ability of these genes to discriminate between different populations of breast cancer patients.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas de Ligação a DNA/biossíntese , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Transativadores/biossíntese , Fatores de Transcrição/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Ubiquitina-Proteína Ligases/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Divisão Celular , Fatores de Transcrição de Resposta de Crescimento Precoce , Feminino , Humanos , Fatores de Transcrição Kruppel-Like , Pessoa de Meia-Idade , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Proteína Smad2 , Proteína Smad7 , Fator de Crescimento Transformador beta , Dedos de Zinco
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