Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A survey of in vitro cytotoxic effects of camptothecin in human epitheliod sarcoma, colon, breast and ovarian carcinomas, glioblastoma, and neuroblastoma (PNET) cell lines, was done. We chose the MTT assay to measure survival and observed that 24 h exposures to camptothecin caused consistently greater toxicity than 1 h exposures. The LD50 for camptothecin was in the 12.5-25 ng/ml range. There was a 10-fold range of growth rates measured by OD after 5 days exposure and varied expression of MDR1 in these cell lines--none of which could be correlated with tumor sensitivity to drug. The most sensitive cell lines were colon and glioblastoma, and the most resistance were ovarian, breast and epithelioid sarcoma.
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PMID:Camptothecin cytotoxic effects in vitro: dependency on exposure duration and dose. 757 68

The karyotypes of 47 pediatric brain tumors (14 cerebellar pilocytic astrocytomas, six cerebral pilocytic astrocytomas, seven anaplastic astrocytomas and glioblastomas, nine medulloblastomas [PNETs], one cerebral neuroblastoma, four ependymomas, and seven miscellaneous other neoplasms) are presented. Most of the pilocytic astrocytomas and ependymomas had normal karyotypes. In contrast, the majority of the anaplastic astrocytomas-glioblastomas were abnormal. The abnormalities included losses and structural abnormalities of chromosomes 9, 13, and 17, and double minutes. There were no losses of chromosomes 10 and 19q or gains of chromosome 7, which are among the most common abnormalities of adult glioblastomas. The chromosomal abnormalities in the medulloblastomas were similar to those reported in the literature but less frequent. Four tumors (choroid plexus papilloma, meningioma, cerebral malignant rhabdoid tumor, and immature teratoma) had losses of chromosome 22.
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PMID:Chromosomal abnormalities in 47 pediatric brain tumors. 762 8

We investigated tyrosine kinase activity of the ret proto-oncogene products (proto-Ret proteins), using a cell lysate of NB-39-nu neuroblastoma cells. The 150 kDa and 170 kDa proto-Ret proteins immunoprecipitated with antibodies against their carboxy-terminal 20 amino acids were shown to be phosphorylated predominantly on tyrosine residues in immunocomplex kinase assay. The level of tyrosine phosphorylation of the 150 kDa proto-Ret protein was approximately 10-fold higher than that of the 170 kDa proto-Ret protein, although both proteins were expressed at similar levels in neuroblastoma cells. This result was confirmed by using a lysate of SK-N-MC human primitive neuroectodermal tumor cells transfected with the ret proto-oncogene. The kinase activity of proto-Ret proteins was significantly inhibited by antibodies against their kinase domain, indicating that these antibodies recognize crucial epitopes for the enzymatic activity. On the other hand, the proto-Ret proteins were not phosphorylated in vivo in NB-39-nu cells and SK-N-MC transfectants.
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PMID:Tyrosine kinase activity of the ret proto-oncogene products in vitro. 768 95

Five brain tumors in infancy were studied histopathologically. Though four of them could be included in primitive neuroectodermal tumor, histopathological findings were diverse. The diagnoses were medulloblastoma, cerebellar neuroblastoma, pineoblastoma, ependymoblastoma and ependymoma. While conventional stain for microscopy exhibited their specific findings, immunohistochemical and electron microscopical studies revealed morphological findings related functional structures of the tumor cells. These methodology is mandatory in order to elucidate cytogenesis and differentiation of infantile brain tumors.
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PMID:Pathology of infantile brain tumor. 769 30

The ability to accurately assess tumor size and orientation to surrounding vital structures is an important consideration during preoperative evaluation. The authors report on nine children with solid tumors (hepatoblastoma [1], neuroblastoma [2], adrenal cortical carcinoma [2], liver adenoma [1], primitive neuroectodermal tumor [PNET] [1], and stage V Wilms' tumor [2]) for whom tumor resectability was questioned because of the tumors' close proximity to major blood vessels (noted through conventional radiographic imaging). The children had scanning with spiral volumetric acquisition computerized tomography, (CT) which obtains images during continuous rotation of the x-ray source while the patient moves at a constant velocity through the gantry. This technique is rapid (18 to 30 seconds), and is similar with respect to radiation exposure; little or no sedation is required, and the contrast dose is lower than that of conventional CT. Three-dimensional reconstruction of spiral CT imaging provided useful information that allowed successful resection in all nine cases. The authors suggest that spiral CT may become an important imaging modality in the preoperative evaluation of pediatric solid tumors and that further evaluation of this new methodology is warranted.
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PMID:The role of spiral (helical) computerized tomography with three-dimensional reconstruction in pediatric solid tumors. 773 57

Malignancies of childhood include a well-defined spectrum of hematolymphoid, organ specific (adrenal, kidney, liver), soft tissue, bone, and nervous system (central and peripheral) neoplasms with variable biology. Small round cell neoplasms, a subset of childhood malignancies, are histologically similar but differ markedly in their histogenesis, therapy, and prognosis. Traditionally, clinical information and light microscopy, with the aid of histochemistry and ultrastructural evaluation, establish a diagnosis or at least narrow the differential diagnosis. Additionally, immunohistology, cytogenetics, and molecular studies have become important in diagnosis and in defining phenotype/genotype, patient treatment modalities, and prognosis in specific cases. The 11;22 chromosomal translocation typifies Ewing's sarcoma, primitive neuroectodermal tumor, and Askin's tumor, as does the resultant chimeric transcript, while expression and amplification of N-myc oncogene are predictive of the prognosis in neuroblastoma. Furthermore, studies of genes and gene products are elucidating mechanisms of oncogenesis and tumor progression.
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PMID:Immunohistology, cytogenetics, and molecular studies of small round cell tumors of childhood. A review. 776 71

Pediatric tumors which are conventionally considered to be small round cell tumors (SRCTs) include the prototypical neuroblastoma as well as rhabdomyosarcoma (RMS), Ewing's sarcoma (ES), malignant lymphoma, and primitive neuroectodermal tumor (PNET). Other malignancies may be considered in the differential diagnosis such as small-cell osteogenic sarcoma, undifferentiated (anaplastic) hepatoblastoma, granulocytic sarcoma, blastemal type Wilms' tumor, and desmoplastic small-cell tumor of the peritoneum. The cytomorphologic features of conventional SRCTs is presented as well as the utility of ancillary studies performed on the aspirated material in making a specific and correct diagnosis. The role of the immediate cytologic assessment of the aspirate is stress, since this is a critical step in formulating an initial diagnostic impression that should prompt the need for additional material for pertinent ancillary studies. Although challenging, FNA cytology of SRCTs of childhood can be diagnostic in the majority of cases, allowing specific therapy to be given to patients with unresectable SRCTs without a tissue biopsy as well as documenting recurrent and/or metastatic disease.
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PMID:FNA biopsy of small round cell tumors of childhood: cytomorphologic features and the role of ancillary studies. 805 Mar 33

The cytotoxic effects of taxol at concentrations of 0.001-1.0 microgram/ml were determined in two human glioblastoma multiforme, two neuroblastoma and two primitive neuroectodermal tumor cell lines. The neuroectodermal cell lines were established from previously treated patients, while the glioblastomas were from untreated patients. At exposure durations of 1, 4 and 24 h there was an inverse taxol concentration-survival relationship for all six cell lines as measured by the MTT method. Significant differences in sensitivity to taxol among these cell lines were observed; the most resistant cell line SK-N-FI is characterized by very high levels of MDR1 expression and the most sensitive SK-N-AS by very low levels. An additional level of complexity concerns a saturation threshold for taxol-induced cytotoxic effects which when reached precludes additional effects of prolonged or additional exposure. Tumors of the brain and peripheral nervous system appear to be sensitive to taxol. However, dosage necessary to maximize cytocidal effects in tumors requires knowledge of at least the range of each tumors constitutive sensitivity to taxol and a way to optimize drug delivery.
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PMID:A saturation threshold for taxol cytotoxicity in human glial and neuroblastoma cells. 810 44

Sixty-seven childhood tumors were studied immunohistochemically for the extracellular matrix element type IV collagen, laminin, and fibronectin. Tumors included Ewing's sarcoma, primitive neuroectodermal tumor, small cell osteosarcoma, neuroblastoma or ganglioneuroblastoma, rhabdomyosarcoma, and lymphoma. It was found that small cell osteosarcoma was often positive for fibronectin but not type IV collagen or laminin, a new observation. In the lymphomas, matrix proteins were rarely found. Ewing's sarcoma was variably positive for type IV collagen and laminin, but fibronectin was absent. Extracellular laminin and fibronectin were found in one of two cases of primitive neuroectodermal tumor. In neuroblastoma and ganglioneuroblastoma, the matrix components were rarely found. These results, discrepant with findings in cultured cells, may reflect the altered capacity of tumors to produce these proteins in vitro, which suggests that caution should be exercised in drawing conclusions regarding the nature or histogenesis of tumors from data obtained with cultured tumor cells. Embryonal rhabdomyosarcoma frequently contained all matrix elements in the extracellular space and in a dotlike pattern in the cytoplasm; alveolar rhabdomyosarcoma rarely contained these proteins and never exhibited the dotlike pattern. The frequent finding of matrix proteins in embryonal rhabdomyosarcoma but only rarely in alveolar rhabdomyosarcoma and the unique immunostaining pattern in embryonal rhabdomyosarcoma may prove to be a useful adjunct in the diagnosis of childhood tumors.
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PMID:Extracellular matrix of small round cell tumors of childhood: an immunohistochemical study of 67 cases. 815 9

Immature teratoma occurs occasionally in the brain of children and contains a large amount of immature neuronal tissue. These primitive neuronal components are a good target for studying the morphology of primitive neuroectodermal tumors, including neuroblastoma, ependymoblastoma, medulloepithelioma and so on. Primitive neural tubes are immunohistochemically and ultrastructurally studied in two cases of primary immature teratoma of the child brains, compared to true rosettes in a case of neuroblastoma, primitive neural tube in the fetal rat brain (9 to 13 days of gestational age). The study also extends to the pathology of PNET. Ultrastructurally the primitive neural tube like structures in two teratomas were virtually identical those of developing fetal rat brains and true rosettes in a neuroblastoma. However, these tubular structures are different from each other in immunohistochemistry. These differences are considered to reflect the different developmental lineage of the tumor cells, that is, neuroblastoma produces only neuroblastic cells, and primitive neural tubes in teratoma both neuroblastic and glioblastic cells. Rejuvenation of neuroblastoma cells seems to render a VIM-positivity of the tumor cells.
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PMID:[Immunohistochemical and ultrastructural studies of intracranial immature teratoma--a comparative observation on neuroblastoma, PNET and ependymal tumor, with a special reference to rosette structures]. 816 54


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