Situaçäo do Retinoblastoma nos últimos 17 anos em Curitiba - Paraná / Retinoblastoma incidence revision in the last 17 years in Curitiba - Paraná

Realizou-se uma revisäo de casos de retinoblastoma em quatro hospitais de Curitiba. Encontraram-se 92 casos nos últimos 17 anos, onde analisou-se: idade em que se estabeleceu o diagnóstico, sexo, tempo decorrido entre o início dos sintomas e o seu diagnóstico, sintomas mais comuns, lateralidade e extensäo do tumor, tempo de acompanhamento e óbito destes pacientes. Conclui-se que o tempo decorrido entre o diagnótico e o início dos sintomas é elevado, pela falta de esclarecimento da populaçäo e falta de trabalho direcionado a classe médica. Isto deverá ser melhorado com a formaçäo de equipes multidisciplinares envolvendo oftalmologistas, pediatras, oncologistas, radioterapeutas, geneticistas, psicólogos, sanitaristas e membros da comunidade

Retinoblastoma x exame do fundo do olho na criança / Retinoblastoma x fundus examination in children

Em que idade devemos fazer o exame do fundo do olho na criança com vistas a diagnosticar precocemente um retinoblastoma? Para responder essa pergunta säo revisados 244 casos de retinoblastoma atendidos, no Serviço de Oftalmologia do Hospital A.C. Camargo da Fundaçäo Antonio Prudente em Säo Paulo, no período de 1 de janeiro de 1975 a 31 dezembro de 1989. Foi analizada a relaçäo entre a idade dos pacientes, o início do tratamento e o estágio de evoluçäo da doença nesse momento. Verificou-se que 88.6 p/cento dos casos tratados até os 18 meses de idade, apresentavam doença intra-ocular, compatível com a cura pela enucleaçäo simples ou até passíveis de tratamento com conservaçäo do globo ocular. Os autores propöem que se incentive o exame do fundo do olho em toda criança até a idade de 18 meses, como forma de diagnóstico precoce dessa doença

Estadiamento no retinoblastoma / Staging in retinoblastoma

Desde meados deste século, várias classificacöes têm sido desenvolvidas para o estadiamento do retinoblastoma. O trabalho clássico de Reese-Ellsworth, baseado nos aspectos clínicos do tumor, foi complementado, posteriormente, com outras classificaçöes que deram ênfase a estrutura histopatológica e a diferenciaçäo celular tumoral. Neste trabalho realizamos uma revisäo crítica das classificaçöes de Reese-Ellsworth e Howarth e col. em suas principais características, usando amostra de 21 pacientes portadores de retinoblastoma. Os resultados mostraram que 80p/cento dos pacientes encontraram-se no estágio V da classificaçäo de Howarth e col., correspondendo aos estágios II, III e IV da classificaçäo de Howarth e col., que se baseia principalmente em aspectos histo-patológicos do tumor. Concluimos que as classificaçöes mais modernas baseadas em estudos histopatológicos, facilitam um conhecimento mais apurado da extensäo da neoplasia, bem como tornam possível a avaliaçäo mais detalhada da efetividade do tratamento

Retinoblastoma: análise cromossômica / Retinoblastoma: cytogenetic study

O artigo refere o resultado da análise cromossômica de 27 portadores de retinoblastoma uni ou bilateral, de ambos os sexos, esporádicos ou familiais, virgens de tratamento ou após 6 meses do término de quimioterapia sistêmica, triados no Ambulatório de Oftalmologia do Hospital A.C. Camargo da Fundaçäo Antônio Prudente/SP. Foi dada preferência àqueles que apresentavam, no quadro clínico geral, malformaçöes congênitas, alteraçöes fenotípicas ou retardo mental. Encontrou-se cromossomopatia inespecífica em 2 pacientes submetidos à poliquimioterapia e cromosssomopatia conhecidas em outros 3 (47,XX+G; 46,XY/47,XY+G; 46,XY/46, XY13q-). Os autores discutem os resultados, a associaçäo de cromossomopatia e retinoblastoma e a indicaçäo do exame do cariótipo nesses pacientes

Endogenous sugar receptor (lectin) profiles of human retinoblastoma and retinoblast cell lines analyzed by cytological markers, affinity chromatography and neoglycoprotein-targeted photolysis.

Plant lectins have previously been employed to map the composition of cellular glycoconjugates on retinoblastoma and other tumor cells. To characterize the cellular receptors in protein-carbohydrate interactions, we have applied cytological markers (fluorescent neoglycoproteins) containing common carbohydrate building-blocks to investigate the presence of endogenous carbohydrate-binding proteins in six human retinoblastoma cell lines and one established human retinoblast cell line. The staining patterns showed similar expression of endogenous sugar receptors in all cell lines, with few qualitative differences. However, application of affinity chromatography using resins with immobilized carbohydrates as affinity ligands to isolate sugar receptors (lectins) with binding specificities for beta-D-galactosides, alpha-D-mannosides, alpha-L-fucosides alpha-D-glucosides and to N-acetyl-D-glucosamine and N-acetyl-D-galactosamine, respectively, revealed significant differences between the cell lines, emphasizing the value of complementary biochemical analysis. To demonstrate the practical use of this type of glycobiochemical profiling, selective photodestruction of retinoblastoma cells in vitro was accomplished following incubation with synthetic neoglycoprotein-hematoporphyrin conjugates and subsequent exposure to light. This phototherapeutical approach thus combined the inherent specificity of a neoglycoprotein for a particular cellular phenotype with targeted drug activation.

Predictive value of flow cytometric DNA-analysis on fresh retinoblastoma tissue.

The cellular DNA content and the distribution of tumour cells in different phases of the cell cycles has been analysed in 8 consecutive enucleated eyes with retinoblastoma. All tumours had abnormal ploidy levels. The analysis did not reveal any specific pattern in 2 tumours which had metastasized compared to 6 local tumours. The flow cytometric analysis alone or in combination with histopathology appeared not to improve the classification of large retinoblastomas.

Retinoid-binding proteins in retinoblastoma tumors.

A combination of Western blot, Northern blot, and radiolabeled ligand-binding techniques was used to investigate retinoid-binding proteins in retinoblastoma (RB) cells from fresh tumors and from 19 RB tumor lines cultured in vitro. Using rabbit anti-bovine cellular retinal-binding protein (CRA1BP) antibodies, no CRA1BP could be detected. As determined by [3H]retinol binding, cellular retinol-binding protein was sometimes not detectable but averaged 2.3 +/- 2.7 means +/- SD, n = 7) pmol [3H]retinol bound/mg protein, similar to adult retina cytosol. Using [3H]retinoic acid as ligand, cellular retinoic acid-binding protein was not detectable in some lines and averaged 1.0 +/- 1.2 (means +/- SD, n = 7) pmol [3H]retinoic acid bound/mg protein, well below the adult retina cytosol level of 94.4 +/- 16.3 (means +/- SD, n = 4) pmol [3H]retinoic acid bound/mg. Using rabbit antibovine interstitial retinol-binding protein (IRBP) antibodies, IRBP of the same molecular mass as human IRBP (135,000) was detected in the medium from all cultured RB cells and averaged 75.9 +/- 19.2 pmol/10(8) cells (bovine IRBP immunochemical equivalents). Cytosol levels were less than 1% of the medium. Using a human IRBP complementary DNA probe, levels of IRBP RNA transcripts in 19 RB cell lines were comparable to adult retina. The Y-79 RB cell line was different from the others; the amount of IRBP in the medium was only about 1% of the RB cell lines. Levels of cellular retinol-binding protein were comparable with the other lines, but cellular retinoic acid-binding protein was 9 times more abundant. IRBP RNA transcripts in Y-79 cells were below the limits of detectability but appeared at low levels after induction of differentiation of Y-79 by 10(-6) M retinoic acid. Although this cell line has been in culture longer than the others, it may also have been initiated at an earlier stage of retinal development.

An immunocytochemical demonstration of calcineurin in human nerve cell tumors. A comparison with neuron-specific enolase and glial fibrillary acidic protein.

Human central and peripheral nerve cell tumors were examined in detail using antibodies to calcineurin, glial fibrillary acidic protein (GFAP) and neuron-specific enolase (NSE). Forty-eight formalin-fixed and paraffin-embedded specimens of human neuronal tumors, including 27 medulloblastomas, were examined. Calcineurin-positive cells were found in all peripheral nerve cell tumors and the two gangliogliomas, whereas 20 of the 27 medulloblastomas and one of the two cerebral neuroblastomas did not contain calcineurin-positive cells. Differentiation of cells along the neuronal lines was positively correlated with calcineurin immunoreactivity. NSE-positive cells were found in all of the tumors with the exception of the one cerebral neuroblastoma. NSE immunoreactivity was not invariably consistent with calcineurin immunoreactivity and non-neuronal cells were often positive. Calcineurin-positive cells were all devoid of GFAP, but NSE-positive cells expressed GFAP in some tumors. GFAP-immunoreactive cells were found only in central nerve cell tumors, and not in peripheral tumors. In addition, GFAP-positive cells in some tumors such as retinoblastoma and medulloblastoma morphologically revealed not only neoplastic but also reactive astrocytic features.

Immunohistochemical characterization of human retinoblastomas in situ with multiple markers.

We studied paraffin-embedded specimens from 18 surgically enucleated eyes with retinoblastoma by peroxidase-antiperoxidase immunohistochemistry with antibodies against glial fibrillary acidic protein, S-100 protein, Leu 7 epitopes, neuron-specific enolase, the 200-kilodalton subunit of the neurofilament triplet polypeptide, and retinal S-antigen. We found that (1) glial fibrillary acidic protein, S-100 protein, and Leu 7 epitopes were detected only in well-differentiated glial cells that were interpreted as reactive and not neoplastic, (2) undifferentiated neoplastic cells expressed both neuron-specific enolase and retinal S-antigen immunoreactivity, and (3) differentiated cells forming Flexner-Wintersteiner rosettes were found to express neuron-specific enolase, retinal S-antigen, and, occasionally, neurofilament protein. These results support the view that retinoblastomas are composed of neuron-committed cells and favor the origin of these tumors from photoreceptor progenitor cells. We did not find any morphologic or immunohistochemical evidence of glial differentiation from tumor cells that would support the concept that retinoblastoma arises from a primitive neuroectodermal cell capable of divergent differentiation along neuronal and glial lines.

Cellular retinoic acid binding protein (CRABP) in retinoblastoma.

Binding proteins for retinoic acid (cellular retinoic acid binding protein, CRABP) have been demonstrated in various cell types, and display the characteristics of receptors. Three retinoblastomas are described. The clinical diagnosis of retinoblastoma was established by ophthalmoscopic echographic and histological examination. One part of the tumor was frozen in liquid nitrogen immediately after surgery and used for the determination of CRABP. CRABP was present in cells from all three tumors. This may indicate sensitivity of this tumor to retinoic acid or synthetic retinoic acid derivatives with biologic activity.

Binding patterns of lectins to human retinoblastoma cells: preliminary findings.

Lectin binding patterns of cultivated retinoblastoma cell lines Y-79 and Mac-7 and freshly isolated tumor tissue revealed membrane-associated sugar residues NAcD-Gal, D-Gal, mannose, and D-GlcNAc. Compared to normal retinal pigment epithelium, LCA positively bound to retinoblastoma cells. Similarities in the glycoconjugate patterns with LV-B-1 cells are shown.

Analysis of retinoblastoma for human adenovirus and human JC virus genome integration.

Human adenovirus groups A and B have an oncogenic potential in newborn rodents. Especially, adenovirus type 12 is known to induce retinoblastoma-like tumor in baboons and transform human embryo retinoblast cells in vitro. Human JC virus is also known to produce a variety of tumors in newborn rodents, including retinoblastoma-like tumor. In this experiment, cell DNAs of human retinoblastomas were assayed for each of the transforming gene sequences of adenovirus groups A, B, C, D and E and for JC virus gene sequences, by using Southern blot hybridization. None of these viral gene sequences were detected at the level of 0.1-0.5 copy per diploid cell DNA in all of 11 retinoblastomas, including 6 retinoblastomas previously examined for adenovirus 12-transforming gene sequences. This led to a conclusion that most, if not all, adenoviruses and JC virus play no essential role in the etiology of human retinoblastoma, although there were experimental models of retinoblastoma induced by these viruses.

Immunohistochemistry of retinoblastomas.

Immunohistochemical stains using neuronal and glial marker proteins were applied to retinoblastomas tissues from 14 children. Among the neurofilament triplet proteins, NF68Kd positive cells were observed in 12. Few NF160Kd positive cells were noted in 2, and NF210Kd positive cells were not detected. The positive ratio of NF68Kd and gamma-enolase seems to relate to the Flexner-Wintersteiner rosettes. Gamma-enolase positive cells were observed in 13. The distribution in tumor tissues was broader than that of NF68Kd positive cells. The immunoreactivities of NF68Kd were in parallel with those of gamma-enolase. Few GFAP positive cells were present around blood vessels, while S-100 protein and MBP positive cells were never observed. Our results indicate that retinoblastoma possesses predominantly neuronal properties, albeit in an immature form.

Immunohistochemical demonstration of glial markers in retinoblastomas.

Twenty retinoblastomas were studied immunohistochemically in order to visualize glial cells. In the retina, the glial cells in the ganglion cell layer and the Müller cells were GFAP positive, while only the glial cells of the ganglion cell layer expressed S-100 reactivity. In the tumours S-100/GFAP positive glial cells were found in areas near the retina and along many tumour vessels. Some S-100 reactive cells previously interpreted as tumour cells were refound in a few tumours. In areas with Flexner-Winterstein rosettes and in areas with light cells showing photoreceptor-like differentiation, glial cells reactive for both S-100 and GFAP were demonstrated. The latter findings may represent differentiation in a glial direction in the more mature parts of retinoblastoma.

Intermediate filaments in the human retina and retinoblastoma. An immunohistochemical study of vimentin, glial fibrillary acidic protein, and neurofilaments.

Fifty-five retinoblastoma specimens were studied by a sensitive immunoperoxidase method to determine the intermediate filament types present in human retina and retinoblastoma. Polyclonal antiserum against vimentin and monoclonal antibodies to glial fibrillary acidic protein (GFAP) and to the 200 kD neurofilament triplet protein were used. In the human retina, Müller's cells coexpressed vimentin and GFAP in most instances, probably as a reactive phenomenon. Surprisingly, the horizontal cells did not stain with any of the antibodies used, and may thus lack intermediate filaments. Also, the meshwork of neural fibers in the inner plexiform layer was unusually sparse. Retinoblastoma cells were found to be devoid of all intermediate filament types studied. The tumors contained, however, vimentin and GFAP in the stromal cells. All neurofilament-positive cells in retinoblastoma apparently derived from infiltrated retina. One retinoblastoma eye was also studied by indirect immunofluorescence microscopy of frozen sections with identical results.

Neurotransmitter systems in morphologically undifferentiated human Y-79 retinoblastoma cells: studies of GABAergic, glycinergic, and beta-adrenergic systems.

Elements of three neurotransmitter systems were investigated in morphologically undifferentiated human Y-79 retinoblastoma cells in suspension culture. Specific gamma-aminobutyric acid (GABA) uptake, GABA binding, and glycine binding were absent from these cells, although the cells had been shown to exhibit an active uptake and release of [3H]glycine. Binding and competition studies using both alpha- and beta-adrenergic ligands indicated the presence of a beta-adrenergic receptor. This finding was confirmed by treatment of the cells with beta-agonists in competition with a beta-antagonist and with an alpha-antagonist; the level of cyclic AMP was competitively stimulated. Therefore, human Y-79 cells in suspension culture contain beta-adrenergic receptors, and not glycinergic or GABAergic ones. Thus, the Y-79 cells may be of use in studying the factors involved in developmental regulation of neurotransmitter function.

Antigenic modulation in retinoblastoma: a flow cytometric study.

Flow cytometry (FCM) was used to investigate antigenic expression and modulation during the cell cycle of Y-79 and WERI-Rb1 tissue cultured retinoblastoma cell lines using a polyclonal anti-Y-79 antibody and fluorescein conjugated lectins. Several Y-79 resting cell populations were identified by FCM analysis of antibody binding, while only a single population with uniform antigen expression was found to exist in the synthetic and mitotic phases. WERI-Rb1 cells bound antibody approximately equally in each phase of the cell cycle. Multiple cell populations with different lectin binding affinities were seen in the resting phase with FITC-concanavalin A, FITC-ricinus communis-60 and FITC-ricinus communis-120 (FITC-RCA-120). During the S-phase of the cell cycle, a higher percentage of cells bound FITC-RCA-120 and FITC wheat germ agglutinin. The relationship between antigenic expression during the cell cycle and treatment considerations in retinoblastoma is discussed.

Dual properties of cultured retinoblastoma cells: immunohistochemical characterization of neuronal and glial markers.

The dual properties of two human retinoblastoma cell lines, WERI-Rb1 and Y79, were investigated with immunohistochemistry. Two neuron-specific markers, dopamine-B-hydroxylase (DBH) and tetanus toxin, and an astrocyte-specific marker, the glial fibrillary acid protein (GFAP), were applied for immunohistochemical reactions. With peroxidase-antiperoxidase (PAP) and immunofluorescence techniques, all of the WERI-Rb1 and Y79 cells showed consistently positive results with both neuronal and glial markers. The findings demonstrate that cultured retinoblastoma cells WERI-Rb1 and Y79 have both neuronal and glial properties.