Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10636 (tau protein)
 5,110 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seventy-one tumors of the central nervous system in children were studied immunohistologically. Thirty-seven were classified histologically as PNETs, of which 35 were located in the cerebellum (medulloblastomas), one in the cerebrum, and one in the spinal cord. The 34 non-PNETs included five ependymomas, seven gangliogliomas, 15 astrocytomas, and seven tumors of other histology. We used monoclonal antibodies specific for neurofilament (NF) triplet proteins, for microtubule associated protein 2 and tau protein and for glial fibrillary acidic protein (GFAP) and myelin basic protein. In addition, a monoclonal antibody to epithelial membrane antigen was applied. The presence or absence of these antigens defined four major groups of PNETs: 1) PNETs not otherwise specified (10 cases), 2) PNETs with neuronal differentiation (eight cases), 3) PNETs with astrocytic differentiation (six cases), and 4) PNETs with both neuronal and astrocytic differentiation (12 cases). One case showed ependymal differentiation. The pattern of expression of NF isoforms in PNETs was reminiscent of that seen during normal mammalian development, such that phosphorylated NF-H was only present in combination with NF-M and NF-L. Among the other central nervous system tumors, all astrocytomas and gangliogliomas were positive for GFAP, and the gangliogliomas also expressed all NF isoforms. Three atypical teratoid tumors and two rhabdoid tumors showed strong positivity for epithelial membrane antigen and also for GFAP. We conclude that the differentiation antigens described here serve to distinguish PNETs from other pediatric central nervous system tumors and to identify subsets of PNETs. Accordingly, PNETs represent a heterogeneous group of pediatric brain tumors capable of neuronal and glial differentiation.
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PMID:Molecular markers of primitive neuroectodermal tumors and other pediatric central nervous system tumors. Monoclonal antibodies to neuronal and glial antigens distinguish subsets of primitive neuroectodermal tumors. 255 87

Ewing's sarcoma/primitive neuroectodermal tumor (EWS/PNET) has a characteristic chimeric oncogene EWS-FLI1, which results from chromosomal translocation t (11; 22), that is believed to initiate tumorigenesis of EWS/PNET. However, the specific details of EWS/PNET oncogenesis and exact role of EWS-FLI1 remain largely unknown. In this study we explored the role of EWS-FLI1 in tumor differentiation using an embryonal carcinoma cell line P19 as a model, with forced expression of EWS-FLI1 in these cells. EWS-FLI1 has been reported to promote neural differentiation in fibroblasts, mesenchymal stem cells and rhabdomyosarcoma cells. We show forced expression of EWS-FLI1 causes absence of retinoic acid-induced neural morphology, and decreases expression of neural-specific proteins MAPT and NCAM. Critical transcriptional factors for neural differentiation and stem cells are also altered in the presence of EWS-FLI1, including decreases in levels of Oct-3 and Pax-6, and an increase in the level of Id2, which is a target of EWS-FLI1. Increased proliferation and decreased apoptotic rates are also observed in P19 cells with forced expression of EWS-FLI1. Our results raise the possibility that arrest of neural differentiation by forced expression of EWS-FLI1 as observed in this study may result from dysregulation of the cell cycle and cell proliferation. Taken together, our results demonstrate that the modulation of neural differentiation in P19 cells which have a stem cell-like pluripotency in vitro can provide a novel model system to study the neural differentiation effects of EWS-FLI1 tumorigenesis of EWS/PNET.
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PMID:Neural differentiation arrest in embryonal carcinoma cells with forced expression of EWS-FLI1. 1862 80