Disease relevance of Ependymoma

• Using single strand conformation polymorphism analysis and direct DNA sequencing, we screened 8 ependymomas and 30 fibrillary astrocytomas from non-NF2 patients for mutations in the coding sequence and portions of the 3' untranslated region of the NF2 gene [1].
• Children with primitive neuroectodermal tumors, anaplastic gliomas, and ependymomas most frequently had LMS [2].
• To evaluate whether morphological subsets of ependymomas are characterized by specific genetic lesions, we analyzed a series of 62 ependymal tumors, including myxopapillary ependymomas, subependymomas, ependymomas, and anaplastic ependymomas, for allelic losses on chromosome arms 10q and 22q and mutations in the PTEN and NF2 genes [3].
• Oligodendroglioma, ependymoma, choroid plexus papilloma, pituitary adenoma, and meningioma cells showed the same integrin pattern as their normal counterparts [4].
• Variable immunoreactivity for MAP2 could be observed in all gliomas with the exception of ependymomas [5].

Psychiatry related information on Ependymoma

• There were 34 cases of mental deficiency, 21 cases of psychosis, 13 of cerebral vascular disease, 10 cases of epilepsy, 4 of acrocephalosyndactyly, 3 of decompensation by slight craniocerebral trauma, and 1 case of ependymoma of the IV ventricle [6].

High impact information on Ependymoma

• Half of the choroid plexus tumors and most of the ependymomas that we studied contained and expressed a segment of T-antigen gene related to SV40 [7].
• Ependymoma carries a poor prognosis, and of the 4 late survivors, the 2 who received GH relapsed [8].
• Identification of a germ-line mutation in the p53 gene in a patient with an intracranial ependymoma [9].
• H&E stained sections revealed an ectopic ependymoma that was strongly positive for GFAP [10].
• Reduced or absent tuberin was observed in 2 of 6 (33%) ependymomas analyzed [11].

Chemical compound and disease context of Ependymoma

• Synaptophysin expression was studied in seven "ependymomas" induced by transplacental administration of ethyl-nitrosourea in rats [12].
• Loss of merlin expression in sporadic meningiomas, ependymomas and schwannomas [13].
• In contrast, most ependymal rosettes in two ependymomas stained positive for EMA along the luminal surface, consistent with a previous study, and were negative for S-Ag [14].
• CONCLUSION: Intramedullary ependymomas become enhanced after administration of gadopentetate dimeglumine; the enhanced borders are usually sharply marginated [15].
• The aim of this study was to examine the range of sensitivity of a panel of short-term cultures derived from different types of malignant childhood brain tumours including medulloblastoma, ependymoma and glioblastoma multiforme to three cytotoxic drugs, lomustine (CCNU), vincristine (VCR) and procarbazine (PCB) [16].

Biological context of Ependymoma

• These results suggest that the NF2 gene may be important in the formation of some ependymomas but the NF2 gene is probably not the critical chromosome 22q tumor suppressor gene involved in astrocytoma tumorigenesis [1].
• A candidate tumor suppressor gene on 22q is the neurofibromatosis 2 (NF2) gene since NF2 patients have an increased susceptibility to ependymomas and astrocytomas [1].
• Alleotyping showed loss of heterozygosity (LOH) involving the wild-type alleles in seven tumors in the family including the ependymoma, which is the first MEN1-related case that shows genetic abnormality in chromosome 11q13, suggesting that MEN1 gene might be involved in the tumorigenesis of a subset of ependymomas [17].
• ERBB receptor signaling promotes ependymoma cell proliferation and represents a potential novel therapeutic target for this disease [18].
• To determine whether NF2 and familial meningioma are allelic mutations, we studied a family with multiple meningiomas and ependymomas in two generations using genetic linkage analysis with DNA markers known to flank the NF2 locus [19].

Anatomical context of Ependymoma

• Such transgenic mice and derived cell lines may represent valid models for analysing (1) the role of SV40 T antigen in ependymoma formation and (2) CFTR function in ependymal cells [20].
• C pneumoniae DNA was searched in 15 surgically clipped and removed aneurysmal sac tissue and in two tumour (an ependymoma of the fourth ventricle and a craniofaringoma) samples by touchdown enzyme time release PCR (TETR PCR) targeting 16S rRNA gene and by nested PCR targeting ompA gene [21].
• Although the luminal surface of the ependymal cells of the human ventricular system is characterized by the presence of cilia with a typical 9 + 2 arrangement of microtubules, cilia are usually described as sparse or absent in ependymal cells of ependymomas [22].
• The PDGF A-chain was expressed in all of the tumors, with the exception of the malignant ependymoma and in both nontumor glial cell cultures [23].
• Finally, ligand blotting and chemical-linking experiments revealed the presence of a approximately 100 kDa putative TTR receptor on the ependymoma cell membrane [24].

Gene context of Ependymoma

• In contrast, none of the eight ependymomas contained keratin, but all were strongly positive for GFAP [25].
• Functional assessment of ERBB-dependent cell signaling and proliferation, in addition to novel therapeutic inhibition of these processes, was conducted using short-term cultures of human ependymoma cells [18].
• We investigated the amplification and overexpression of mdm2 gene, whose product (MDM2) is considered to be one of the major cellular regulators of p53-mediated growth control, in 26 specimens of ependymomas obtained from 20 patients [26].
• Results showed that VEGF was moderately to strongly expressed in 8 of 10 ependymomas and in all anaplastic oligodendrogliomas and glioblastoma multiforme cases [27].
• p14ARF protein (FL-132) immunoreactivity in intracranial ependymomas and its prognostic significance: an analysis of 103 cases [28].

Analytical, diagnostic and therapeutic context of Ependymoma

• The xenograft, HxBr5, was established from a fourth ventricular ependymoma, locally recurrent in an 11-yr-old girl who had been treated with radiation therapy to the posterior fossa [29].
• To determine whether TSC2 RNA and protein are reduced in astrocytomas from individuals without tuberous sclerosis, reverse transcriptase-polymerase chain reaction and immunoblotting analyses were performed on 49 adult astrocytomas, 10 pediatric astrocytomas, and 13 ependymomas [11].
• In order to test this hypothesis further, 101 myxopapillary, conventional, and anaplastic ependymomas (51 spinal and 50 intracranial tumors) were tested for RB and p16 deletions using fluorescence in situ hybridization [30].
• Additionally, frozen tissue from nine ependymomas (four intracranial and five spinal) was obtained for Western blot analysis for merlin, 4.1B and 4.1R expression [31].
• Treatment of ependymomas relies on surgery combined with radio- or chemotherapy, but the efficiency of chemotherapy is limited, probably because of their multidrug resistance (MDR) phenotype [32].

References