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4.
Am J Pathol ; 137(1): 85-92, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1695484

RESUMO

Basic fibroblast growth factor (bFGF) is thought to be of major importance for fibrosis and angiogenesis. Despite intensive studies dealing with the biochemistry and multiple biologic effects of bFGF, the cellular distribution is virtually unknown. Therefore, using the indirect immunoperoxidase technique, we examined the effect of bFGF on a large pattern of normal, inflammatory, and tumorous human tissues. Staining was performed on cryostat sections with a highly specific affinity-purified antiserum. In normal tissues, especially those of the thymus and placenta, mainly dendritic cells contained the growth factor. High levels of bFGF were also detected in basal cells and gland epithelial cells of skin biopsies. A conspicuous expression was observed in chronic inflammatory tissues corresponding to a generally pronounced proliferation of fibroblasts and endothelial cells in these situations. Tumors revealed a very heterogenous staining pattern. In some lesions, bFGF was predominantly present in infiltrating and endothelial cells. In several, neoplasms tumor cells exhibited an intensive staining. In some, especially vascular tumors, bFGF could not be detected. From the staining results it is concluded that angiogenesis is not simply controlled by the presence of bFGF but is mediated by a balance of several angiogenic inducers and inhibitors.


Assuntos
Fatores de Crescimento de Fibroblastos/análise , Células Sanguíneas/análise , Fatores de Crescimento de Fibroblastos/imunologia , Humanos , Inflamação/metabolismo , Tecido Linfoide/análise , Neoplasias/análise , Neovascularização Patológica , Pele/análise , Coloração e Rotulagem
5.
Int J Dev Biol ; 34(2): 309-17, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1696829

RESUMO

We have developed a biochemical method for purifying human tenascin from cultured fibroblasts or the culture medium. The method is a series of biochemical procedures including gel filtration, gelatin gel affinity chromatography and ion-exchange high performance liquid chromatography. The final preparation was identified as tenascin from its immunological cross-reactivity to antibody against chicken tenascin, strong hemagglutination activity which has been reported to be one of the biological functions of chicken tenascin, and from the electron microscopic study demonstrating a six-armed structure. Gel chromatography showed that intact human tenascin has an apparent molecular weight of over one million. Analysis of the purified tenascin with SDS-PAGE under reducing conditions demonstrated that tenascin consists of two kinds of subunits (250K and 190K). We established rat x mouse heterohybridoma cell lines which produce tenascin-specific antibodies. One monoclonal antibody (RCB1) was selected for immunohistochemical study and partially characterized. RCB1 bound native tenascin but not reduced and alkylated tenascin. Immunohistochemistry of normal and neoplastic tissues demonstrated that RCB1 bound the connective tissues surrounding the cancer nests and various normal tissues including interstitium of renal distal tubule, periosteum, endosteum, smooth muscles of digestive tract and media of arteries and arterioles.


Assuntos
Moléculas de Adesão Celular Neuronais/isolamento & purificação , Fibroblastos/análise , Anticorpos Monoclonais , Moléculas de Adesão Celular Neuronais/imunologia , Moléculas de Adesão Celular Neuronais/farmacologia , Linhagem Celular , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Hemaglutinação , Humanos , Hibridomas/imunologia , Técnicas Imunoenzimáticas , Microscopia Eletrônica , Estrutura Molecular , Peso Molecular , Neoplasias/análise , Tenascina , Distribuição Tecidual
7.
Am J Clin Pathol ; 93(5): 637-42, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2327365

RESUMO

With nuclei extracted from paraffin-embedded tissues, resolution of normal diploid DNA and abnormal near-diploid/aneuploid populations by flow cytometry (FCM) is especially difficult. These samples, compared with fresh tissue, tend to show a broader DNA distribution, appearing as a wide (high) coefficient of variation (CV) of the G0/G1 peak. To address the question of whether there may be aneuploid populations hidden in wide CV diploid G0/G1 peaks, the authors measured DNA content in nuclei extracted from paraffin-embedded tumor tissue by morphometric image analysis (IA) in addition to FCM. Of 29 samples showing little evidence of DNA aneuploidy by FCM, in 20 of 20 with G0/G1 CVs greater than or equal to 5.50% there was an aneuploid population when analysis was performed by IA. Of the remaining nine samples with CVs less than or equal to 4.41%, all were diploid in the G0/G1 region by both FCM and IA. The presence of aneuploid populations in FCM distributions with wide CV G0/G1 peaks can be confirmed by IA.


Assuntos
Aneuploidia , DNA de Neoplasias/análise , Citometria de Fluxo , Processamento de Imagem Assistida por Computador , Neoplasias/análise , DNA de Neoplasias/genética , Densitometria , Diploide , Citometria de Fluxo/métodos , Humanos , Neoplasias/genética , Análise de Regressão
8.
Oncology (Williston Park) ; 4(4): 116-22; discussion 122, 125-6, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2143921

RESUMO

The identification of prognostic factors is an important area of cancer research. This article contains an introduction to the uses of prognostic factors, statistical methods for their identification, and a summary of the literature concerning the evolution of serum beta 2 microglobulin as a prognostic factor in multiple myeloma.


Assuntos
Biomarcadores Tumorais/análise , Ensaios Clínicos como Assunto , Mieloma Múltiplo/metabolismo , Neoplasias/análise , Microglobulina beta-2/análise , Feminino , Humanos , Masculino , Mieloma Múltiplo/terapia , Neoplasias/terapia , Valor Preditivo dos Testes , Prognóstico
9.
Clin Lab Med ; 10(1): 59-76, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2184980

RESUMO

An ideal immunohistochemical screening panel would be one in which each antibody is 100% sensitive and specific for the target cell type (e.g., markers for epithelial neoplasms, lymphomas, sarcomas, etc.). Anyone who has practiced immunochemistry is well aware that this situation does not exist. High sensitivity is hindered by the loss of key antigens through formalin fixation and routine tissue processing. Although sensitivity can be improved by dealing with fresh-frozen, lyophilized, or plastic-embedded specimens, these procedures are often perceived as inconvenient by pathologists. Specificity is a more insidious problem. With the advent of monoclonal antibody technology, many individuals equated the monospecificity (e.g., marking one antigen a determinant) with tissue specificity. This, of course, is not the case as determinants recognized by one monoclonal antibody may be expressed on cells of different lineage. High sensitivity and high specificity are important for different reasons. By definition, an undifferentiated neoplasm lacks morphologic features to unequivocally substantiate sarcoma, lymphoma, carcinoma, or melanoma. Thus, antibodies with low sensitivity that fail to mark a significant percent of cases will provide inconclusive or erroneous information. The failure of an antibody to stain a particular tissue could be a true-negative (valuable information) or a false-negative (misleading information) result. Obviously, when antibodies have a sufficiently low sensitivity, their use is a liability rather than an advantage. Specificity is obviously important. When an undifferentiated neoplasm is found to be "positive" for a particular marker, there is a tendency to immediately categorize the neoplasm. In this setting, when histologic features of cellular differentiation are totally lacking, an extreme degree of trust is being placed on the immunohistochemical technique. From our earlier discussion it is apparent that perfect sensitivity and specificity do not exist among most immunohistochemical reagents. Accordingly, the safest approach is to use a panel of antibodies that will disclose anomalous immunohistochemical reactions (e.g., a neoplasm positive for both keratin and LCA). Specimens from such cases should be carefully evaluated with additional monoclonal antibodies and scrutinized by light microscopy. Furthermore, while immunohistochemistry provides for rapid and cost-effective diagnosis, electron microscopy may still contribute valuable information. Despite our best intentions and desires, it is also clear that a small percentage of "undifferentiated" neoplasms will remain undifferentiated. Quality control and quality assurance are two final, but important, issues to address. An extraordinary large number of variables in tissue selection, fixation, and processing can skew results.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Biomarcadores Tumorais/análise , Imuno-Histoquímica , Neoplasias/patologia , Patologia Cirúrgica , Antígenos de Neoplasias/análise , Proteínas do Citoesqueleto/análise , Citoesqueleto , Diagnóstico Diferencial , Humanos , Neoplasias/análise
10.
Clin Lab Med ; 10(1): 77-103, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2184981

RESUMO

The focus of this review has been the application of MAbs as adjuncts in the interpretation of cytology specimens. It is evident that most if not all of the MAbs studied thus far are neither completely tumor-specific nor -sensitive; however, when used to address a directed clinical question, they may be "operationally specific." More important, there continues to be no current substitute for the understanding and practice of sound diagnostic cytopathologic principles. Ultimately, the application of MAbs resides in the importance of tumor-associated antigen expression and phenotyping of tumors with therapeutic and prognostic implications.


Assuntos
Anticorpos Monoclonais , Citodiagnóstico , Neoplasias/diagnóstico , Biomarcadores Tumorais/análise , Biópsia por Agulha , Diagnóstico Diferencial , Epitélio/patologia , Exsudatos e Transudatos/citologia , Humanos , Neoplasias/análise , Neoplasias/patologia , Lavagem Peritoneal
11.
APMIS ; 98(3): 191-9, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1690556

RESUMO

The immunohistochemical approach to tumor typing has dramatically improved our possibilities in the objective diagnosis of neoplasms. Use of optimal material and careful techniques will help to maintain good sensitivity, specificity, and reproducibility of immunohistochemistry. However, the complexity of antigen patterns in tumors, and lack of comprehensive knowledge about them requires caution in the interpretation of results, and may prohibit the simple use of diagnostic algorithms. Especially it is not certain whether the results obtained from typical representatives of various tumor entities will pertain to borderline cases and to undifferentiated variants of the same entities. Use of panels of antibodies rather than the use of single "diagnostic" tests will help to avoid these diagnostic pitfalls. However, all tumor types do not have immunohistochemically distinctive features. This emphasizes the need to use other techniques in such cases, and also suggests that some entities, such as malignant fibrous histiocytoma, are from the point of view of immunohistochemistry diagnoses only made by exclusion rather than being specifically diagnosable entities. All diagnostic immunohistochemistry has to be interpreted in the context of standard histological examination.


Assuntos
Imuno-Histoquímica/métodos , Neoplasias/análise , Antígenos de Neoplasias/análise , Diagnóstico Diferencial , Fixadores , Formaldeído , Secções Congeladas , Humanos , Queratinas/análise , Neoplasias/classificação , Peptídeo Hidrolases
12.
Int J Cancer ; 45(3): 457-61, 1990 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-1968437

RESUMO

The human homolog of the rat neu oncogene, HER2 (also termed c-erbB2) has been demonstrated in amplified form in human breast tumors with poor prognosis. Although amplification of the gene correlates with expression of a 185-kDa transmembrane glycoprotein, no extensive information is available regarding the extent of tissue and tumor specificity of this gene product. We have addressed this issue by immunohistochemically evaluating the expression of p185 HER2 in normal tissue and various tumors using monoclonal antibodies (MAbs) to distinct epitopes of its extracellular domain. No detectable levels of p185 HER2 were found in fetal tissues analyzed, with the exception of renal tubules in 2 out of 3 specimens tested and in intestinal epithelium. In adult tissues, detectable levels of this glycoprotein were found in a restricted number of cell types, the expression being heterogeneous among individuals and cell histotypes. Among the neoplasms assayed p185 HER2 was expressed in 46% of primary breast cancers, in 28% of ovarian tumors and in 30% of colon rectum malignancies. No male breast adenocarcinomas were p185-positive. A large number of other tumors tested revealed only a low incidence of expression of the p185. In metastatic breast tumors p185 HER2 was demonstrated homogeneously among multiple autologous lesions and almost invariably (80%) the expression of p185 in the primary lesion correlated with that of the deriving metastases. Our findings indicate that the expression of the p185 HER2 represents a tumor marker of clinical relevance in breast cancer. Whether this holds true for other malignancies remains to be explored.


Assuntos
Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Proteínas Oncogênicas Virais/genética , Proteínas Proto-Oncogênicas/análise , Anticorpos Monoclonais , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Humanos , Neoplasias/análise , Proteínas Proto-Oncogênicas/genética , Receptor ErbB-2
13.
J Clin Endocrinol Metab ; 70(3): 661-9, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1968467

RESUMO

The binding characteristics of several somatostatin (SS-14) analogs developed in our laboratory were examined in various human and animal tumors and normal tissues. In rat cerebral cortex and human breast cancer membranes the interaction of SS-14 with its binding sites was rapid, specific, saturable, linear with protein concentrations, and dependent on time and temperature. Analysis of kinetic and equilibrium experimental data showed that the interaction of [125I-Tyr11]SS-14 with the binding sites in all normal and tumoral tissue specimens was consistent with the presence of a single class of noncooperative binding sites. Superactive octapeptide analogs of somatostatin-containing hexapeptide sequences Cys-Phe-D-Trp-Lys-Thr-Cys or Cys-Tyr-D-Trp-Lys-Val-Cys showed significant binding affinities to SS-14 receptors. Among these analogs, D-Trp-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH2 (RC-98-I) showed the highest binding affinity to normal human pancreatic tissue and human pancreatic adenocarcinoma. In contrast, Sandostatin (SMS 201-995) bound only to normal pancreas, not to human pancreatic cancers. Analog RC-98-I also showed a high binding to human and rat prostate cancers. In human epithelial ovarian cancers and an arrhenoblastoma, analogs D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Trp-NH2 (RC-95-I), D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH2 (RC-121) and D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH2 (RC-160) appeared to be the most potent in displacing labeled SS-14. Analogs Ac-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH2 (RC-101-I) as well as RC-121, RC-160, and RC-95-I, but not SMS-201-995, showed high binding affinity in human breast cancers. In specimens of human meningioma the highest binding was found with analogs RC-121, RC-95-I, and RC-101-I. Since marked variations in binding affinities were noted for several analogs in the tissues of origin and the tumors, this suggest that differences may exist between somatostatin receptors not only in normal vs. cancerous tissues, but also among various tumors. Our findings also imply that some analogs could be therapeutically superior to others in the treatment of certain tumors.


Assuntos
Neoplasias/análise , Receptores de Neurotransmissores/análise , Somatostatina/análogos & derivados , Sequência de Aminoácidos , Animais , Sítios de Ligação/efeitos dos fármacos , Ligação Competitiva , Neoplasias Encefálicas/análise , Neoplasias da Mama/análise , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Neoplasias Ovarianas/análise , Neoplasias Pancreáticas/análise , Neoplasias da Próstata/análise , Ratos , Ratos Endogâmicos , Receptores de Somatostatina , Somatostatina/farmacologia , Células Tumorais Cultivadas
14.
Am J Clin Oncol ; 13(1): 70-4, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2305720

RESUMO

We developed an autoradiographic screening test for hormone sensitivity of single cell suspensions of tumor tissues on cell mats, which inhibited the growth of normal cells alone. We applied this method to our newly established KSE-1 line derived from esophageal carcinoma and compared this method with well-established cytoplasmic and nuclear assays. Our assay, though taking longer to implement and providing only qualitative information, requires significantly smaller specimens than the current biochemical assay and will predict the hormone sensitivity of only viable neoplastic cells.


Assuntos
Autorradiografia/métodos , Neoplasias/análise , Receptores de Estradiol/análise , Animais , Neoplasias da Mama/análise , Carcinoma/análise , Núcleo Celular/análise , Células Cultivadas , Citosol/análise , Neoplasias Esofágicas/análise , Estradiol/metabolismo , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Células Tumorais Cultivadas
15.
Pathologica ; 82(1077): 71-81, 1990.
Artigo em Italiano | MEDLINE | ID: mdl-2362786

RESUMO

The role of immunocytochemistry in fine-needle aspiration cytology. The Authors review the literature about fine-needle aspiration biopsy cytology in different organs and show the feasibility of the application to cytological specimen of immunocytochemical methods. Thus, they analyze 15 cases of tumors of various localization diagnosed by F.N.A.C. where immunocytochemistry succeeded in their correct typization. They also show the encouraging results of the immunocytochemical search of specific hormones in pituitary adenomas. Therefore the Authors emphasize the great usefulness of immunocytochemical techniques for the improvement of the diagnostic possibilities in the fine-needle aspiration cytology.


Assuntos
Anticorpos Antineoplásicos/análise , Biópsia por Agulha , Neoplasias/patologia , Adolescente , Adulto , Estudos de Avaliação como Assunto , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias/análise
16.
Br J Cancer ; 61(1): 65-8, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2297492

RESUMO

Rice et al. (1986) have described a flow cytometric method where the non-fluorescent probe monochlorobimane (mBCl) forms a fluorescent adduct with cellular glutathione (GSH) under the action of glutathione-S-transferase. We show here that for EMT6 carcinosarcoma cells there is a close correlation between mean cell fluorescence, expressed as a ratio to that of fluorescence calibration beads, and biochemically determined GSH content over the range 0.2-2.0 fmol cell-1. Single cell suspensions from 14 human cancers were prepared by 23-gauge needle aspiration or mechanical disaggregation of surgical specimens, stained using mBCl and examined by flow cytometry. There was a wide range in individual cell fluorescence, which in contrast to EMT6 cells was not strongly correlated with Coulter volume. By comparing tumour cell fluorescence to that of calibration beads, and assuming that the relationship with GSH content for EMT6 holds for other cells, a mean GSH content of 0.95 fmol cell-1 was derived for nine carcinomas, and 0.21 fmol cell-1 for five non-Hodgkin's lymphomas. Although this semi-quantitation needs further validation, the method used here is rapid, gives an indication of heterogeneity of tumour cell GSH content, and can be applied to fine needle biopsy samples. It therefore shows promise as a means for studying prospectively the relationship of GSH content to clinical drug and radiation sensitivity, and for monitoring the effects of agents such as buthionine sulphoximine which are intended to improve treatment results through tumour cell GSH depletion.


Assuntos
Citometria de Fluxo , Glutationa/análise , Neoplasias/análise , Biópsia por Agulha , Feminino , Humanos , Linfoma não Hodgkin/análise , Linfoma não Hodgkin/patologia , Masculino , Neoplasias/patologia
17.
Biotechniques ; 8(1): 70-5, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2322456

RESUMO

A rapid method for the measurement of the immunoreactive fraction of a radiolabeled monoclonal antibody or antibody fragment has been developed. This may be used as a quality control test prior to patient administration of the radiolabeled antibody preparation. The test employs solid phase antigens and the assay is conducted under conditions of antigen excess. Assay parameters have been evaluated and a standardized procedure has been developed. The assay has been compared to a standard extrapolation method and found to give approximately the same result. The test has been used on four different radiolabeled antibodies currently in clinical trials in patients with colorectal cancer. Mean immunoreactive fractions for these radiolabeled antibodies ranged from 35 to 65% and the variability of the immunoreactive fraction ranged from 140 to 240% for different antibodies. We conclude that the quality, defined as the immunoreactive fraction, of radiolabeled antibodies is both low and highly variable, indicating the need for a quality control test of these radiopharmaceuticals in the clinic prior to patient administration.


Assuntos
Anticorpos Monoclonais/análise , Anticorpos/imunologia , Neoplasias/análise , Radioimunoensaio/normas , Animais , Reações Antígeno-Anticorpo , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/análise , Neoplasias da Mama/análise , Neoplasias do Colo/análise , Humanos , Camundongos , Controle de Qualidade
19.
Am J Surg Pathol ; 14(1): 35-43, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2294779

RESUMO

We analyzed the distribution of chromogranins A and B in normal and neoplastic endocrine tissues with secretory granules using 35S-labeled and biotin-labeled oligonucleotide probes by in situ hybridization (ISH). Both radioactive and nonradioactive probes detected messenger RNAs (mRNAs) in frozen and paraffin tissue sections. Endocrine tissues with variable immunoreactivities for chromogranin A protein, such as small-cell lung carcinomas, neuroblastomas, insulinomas, and parathyroid adenomas, expressed the mRNA for chromogranins A and B in most cells. Some technical problems with the biotinylated probes included nonspecific nuclear staining and endogenous alkaline phosphatase, which was not completely abolished by levamisole pretreatment. A differential distribution of chromogranins A and B was seen in pituitary prolactinomas, which expressed abundant chromogranin B but not chromogranin A mRNAs, and in parathyroid adenomas, which expressed abundant chromogranin A but only small amounts of chromogranin B mRNAs. These results indicate that ISH can be used to detect chromogranins A and B in endocrine tissues with radioactive and biotinylated oligonucleotide probes and that the mRNAs for chromogranin A and B are demonstrable in some tumors even when the chromogranin proteins cannot be detected by immunohistochemistry.


Assuntos
Biotina/análise , Cromograninas/análise , Glândulas Endócrinas/análise , Doenças do Sistema Endócrino/metabolismo , Neoplasias/análise , Proteínas do Tecido Nervoso/análise , Northern Blotting , Humanos , Hibridização de Ácido Nucleico , Sondas de Oligonucleotídeos , RNA Mensageiro/análise , RNA Neoplásico/análise , Radioisótopos de Enxofre
20.
Neoplasma ; 37(3): 333-42, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1695327

RESUMO

Reactivity patterns of seven mouse monoclonal antibodies to human keratin 7 were compared using immunoblotting and immunohistochemistry on cultured cells and normal human and animal tissues. Differences in keratin specificities as determined by two-dimensional immunoblots and interspecies cross-reactivity data on 8 mammalian species suggest that at least six nonidentical epitopes of the keratin 7 molecule are recognized by this panel of reagents. Immunohistochemical examination of a panel of various human neoplasms with monoclonal antibodies monospecific for keratins 7, 18 and 19 revealed potential value of keratin subtyping in differential diagnosis of tumors in general and in subclassification of carcinomas in particular.


Assuntos
Anticorpos Monoclonais , Queratinas/imunologia , Neoplasias/diagnóstico , Animais , Neoplasias da Mama/diagnóstico , Neoplasias do Colo/diagnóstico , Reações Cruzadas , Imunofluorescência , Humanos , Proteínas de Filamentos Intermediários/análise , Queratinas/análise , Neoplasias/análise , Coloração e Rotulagem , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/diagnóstico
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