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PubMed1990

Epidermal growth factor receptors on ependymomas and other brain tumors.

Epidermal growth factor receptor (EGFR) and transferrin receptor levels were determined in 14 intracranial neoplasms (four glioblastomas multiforme, four medulloblastomas, four ependymomas, one cerebellar astrocytoma, and one acoustic neurinoma) and in four samples of "normal" brain tissue. A competitive radioreceptor assay with 125I-epidermal growth factor and 125I-transferrin was performed using the primitive neuroectodermal tumor-derived TE-671 tissue-culture cell line as a standard. Epidermal growth factor receptors were present on TE-671 cells, all four ependymomas, and two of the four glioblastomas multiforme. The number of EGFR's per cell for ependymomas were estimated to range from 1000 to 6000. Transferrin receptors were detected on TE-671 cells, two of the four medulloblastomas, and one of the four glioblastomas multiforme. A cell surface binding assay, performed directly on the rat ependymal cell monolayer, was also analyzed. The identification of EGFR's on ependymomas and TR's on medulloblastomas suggests that malignant central nervous system tumors that spread by cerebrospinal fluid pathways may be treatable by intrathecal antibody-toxin conjugates. The presence of EGFR's on all of the ependymomas may reflect a role of the receptor in the malignant phenotype of this tumor.

Animals↗
PubMed1996

Carcinosarcoma of the uterus with extensive neuroectodermal differentiation.

A case of uterine carcinosarcoma with extensive neuroectodermal differentiation occurring in a 54-year-old woman is described. Microscopically, the endometrial tumour was predominantly composed of a sheet-like proliferation of small- and medium-sized cells. These cells were characterized by fibrillary cytoplasmic processes, rosette-like formations, perivascular palisading patterns, and immunoreactivity for glial fibrillary acidic protein, synaptophysin, leu 7 and neuron-specific enolase. In limited areas, features of conventional carcinosarcoma, including squamous cell carcinoma, leiomyosarcoma and islands of the above mentioned small- to medium-sized cells that were intermingled, were observed. The tumour was aneuploid by flow cytometry. The patient is alive with tumour for three months. It is suggested that at least some cases of uterine primitive neuroectodermal tumour may be explained by one-sided neuroectodermal development within a carcinosarcoma.

Biomarkers↗
PubMed2002

The molecular pathology of p53 in primitive neuroectodermal tumours of the central nervous system.

One hundred and one pre-treatment primary central primitive neuroectodermal tumours were analysed for the expression of p53 protein by immunohistochemistry using the monoclonal antibody DO-7. The staining intensity was classified into four groups: strong, medium, weak and negative and strong staining intensity was associated with the poorest survival. DNA sequencing of the p53 gene was performed in 28 cases representing all four staining groups. Mutations were found in only three of the strong staining tumours suggesting that DNA mutations were not common events and that in the majority of the tumours with over-expressed p53, the protein was likely to be wild-type. Results of immunohistochemistry showed a significantly positive relationship between the expression of p53 and Bax and Bcl-2 proteins, but not Waf-1. Multivariate analyses supported the prognostic value of p53 immunostaining in central primitive neuroectodermal tumours and also of age and gender of patients.

Adolescent↗
PubMed1996

Gangliosides modulate the growth rate and cell phenotype of a murine primitive neuro-ectodermal tumour.

Intratumoural administration of gangliosides (GSD) into a murine primitive neuro-ectodermal tumour, growing in the epicranial subcutaneous tissue of syngenic rats, results in a decrease in the tumour growth rate and causes a more differentiated phenotype of tumour cell, with immunohistochemical expression of neuronal markers. These findings suggest that the potential usefulness of intralesional administration of GSD for the control of tumours of primitive neuro-epithelial character could be considered.

Animals↗
PubMed1997

Peripheral primitive neuroectodermal tumour with ganglioneuroma-like areas arising in the cauda equina.

Peripheral primitive neuroectodermal tumour (pPNET or peripheral neuroepithelioma) is one of the malignant small round cell tumours of peripheral nerves, soft tissues and bones, but rarely originates in the spinal canal. We report an example of pPNET arising in the cauda equina of a 14-year-old Japanese boy. At surgery, a well-demarcated tumour measuring 2 x 4 cm in diameter and involving one of the nerve roots of the cauda equina was located within the intradural space with no evidence of extradural extension. Microscopically the tumour was made up of sheets of closely packed small round cells, associated with ganglioneuroma-like islands. Immunohistochemically, the small round tumour cells were intensely positive for neuron-specific enolase (NSE), an MIC2 gene product (O13) and beta 2-microglobulin, whereas the foci with ganglion cell-like cells reacted positively to NSE, synaptophysin and beta 2-microglobulin but were negative for O13. A chimeric transcript of the EWS/FLI-1 fusion gene detected by a nested reverse transcriptase-polymerase chain reaction using formalin-fixed paraffin-embedded tissue justified the diagnosis of pPNET. Only 6 cases of PNET in the cauda equina have been described in the literature, and this is the first case of a pPNET with ganglio-neuroma-like areas. This finding suggests that the primitive tumour cells of pPNET may respond to unknown inductive effects and express a ganglion cell-like morphology.

Adolescent↗
PubMed1996

BCL2 regulates neural differentiation.

A main function attributed to the BCL2 protein is its ability to confer resistance against apoptosis. In addition to the constitutively high expression of BCL2, caused by gene rearrangement in follicular lymphomas, elevated expression of the BCL2 gene has been found in differentiating hematopoietic, neural, and epithelial tissues. To address the question of whether the expression of BCL2 is a cause or consequence of cell differentiation, we used a human neural-crest-derived tumor cell line, Paju, that undergoes spontaneous neural differentiation in vitro. The Paju cell line displays moderate expression of BCL2, the level of which increases in parallel with further neural differentiation induced by treatment with phorbol 12-myristate 13-acetate. Transfection of normal human BCL2 cDNA in sense and antisense orientations had a dramatic impact on the differentiation of the Paju cells. Overexpression of BCL2 cDNA induced extensive neurite outgrowth, even in low serum concentrations, together with an increased expression of neuron-specific enolase. Paju cells expressing the anti-sense BCL2 cDNA construct, which reduced the endogenous levels of BCL2, did not undergo spontaneous neural differentiation. These cells acquired an epithelioid morphology and up-regulated the intermediate filament protein nestin, typically present in primitive neuroectodermal cells. The manipulated levels of BCL2 did not have appreciable impact on cell survival in normal culture. Our findings demonstrate that the BCL2 gene product participates in the regulation of neural differentiation.

Adolescent↗
PubMed1979

Cerebral medulloepithelioma. Report of a case with multiple divergent neuroepithelial differentiation.

A cerebral medulloepithelioma, a rare embryonal multipotential central neuroepithelial neoplasm of childhood, is described, bringing to 16 the total number of cases reported in the literature. It is the first example recorded to date which displayed the entire range of differentiation from embryonal to mature cells, of both glial and neuronal lineage (i.e., primitive medullary epithelium, spongioblasts, astrocytes, oligodendroglia, ependymal cells, neuroblasts, and mature ganglion cells). The significance of this tumor as a paradigm of multipotential divergent neuroepithelial differentiation is discussed.

Adolescent↗
PubMed1977

Fine structure of medulloepithelioma.

A survey of published cases of medulloepitheliomas indicates that this tumor is highly malignant (average course 6 months), occurs in early childhood (average age 4,4 years) and has no sex predilection. Although it may originate in any part of the central nervous system, it is most common in the cerebral hemispheres. The first case studied with the electron microscope is reported here. The fine structure of the tumor is similar to that of the fetal neural tube in showing a primitive epithelium having uniform nuclei rich in chromatin but little cytoplasm and sparse organelles; it rests on a distinct basement membrane. The epithelial surface lacks cilia or microvilli and is covered with an irregular amorphous coat which is probably the cause of the light-microscopic misinterpretation of an inner limiting membrane. The lateral cell surfaces lack interdigitations but show extensive primitive forms of cell junctions. The case presented is also unusual in being the second case on record originating in the cerebellum and the first showing massive seeding along the spinal canal.

Cell Membrane↗
PubMed1999

Adult primitive neuroectodermal tumour. A case report and review of the literature.

A 19-year-old woman presented with left-sided sensorineural hearing loss. She was found to have a left cerebellopontine angle tumour, thought to be an acoustic neuroma on MRI, and was treated with radiosurgery. There was no evidence of tumour on MRI at 6 months. After 1 year, she was admitted with further neurological symptoms. Repeat MRI showed multiple craniospinal tumours. Biopsy of the cerebellar tumour revealed it to be a primitive neuroectodermal tumour (PNET). This is a rare tumour in this age group and its management is discussed.

Adult↗
PubMed1986

Primitive neuroectodermal (neuroepithelial) tumour of soft tissue of the neck in a child: demonstration of neuronal and neuroglial differentiation.

A 4-year-old girl had a pathologically proven primitive neuroectodermal (neuroepithelial) tumour of soft tissue in the left posterolateral aspect of the neck. The neoplasm consisted of primitive neuroepithelial cells forming Homer Wright rosettes, mature ganglion cells and astrocytes. Astroglia were identified by localization of cytoplasmic glial fibrillary acidic protein (GFAP). Striking similarity is noted between the current tumour and those found in the central nervous system, including cerebellar medulloblastomas. The diverse cellular elements of the present primitive neuroectodermal neoplasm suggest an origin of the tumour from the neuroectodermal component of an ectomesenchymal remnant of the neural crest. Differentiation of the neuroectodermal component of the neural crest into primitive neuroepithelial cells could result in the occurrence of a primitive neuroectodermal neoplasm which may further differentiate into neurons and neuroglia.

Cell Differentiation↗
PubMed1997

Disseminated congenital neuroblastoma involving the placenta.

Neuroblastoma, a tumor of primitive neuroectodermal cells, is one of the most common solid malignancies of neonates. Placental metastases have been described in rare cases of congenital neuroblastoma, usually in association with hydrops fetalis, placentomegaly, and widespread disease in the neonate. We report a case in which the unexpected diagnosis of neuroblastoma was made based on the postnatal finding of tumor emboli confined to fetal vessels of the placenta. Radiation and chemotherapy were given based on this diagnosis, obviating the need for an invasive diagnostic procedure.

Adult↗
PubMed1999

Intraspinal primitive neuroectodermal tumour: report of two cases and review of the literature.

Two patients with primary intraspinal primitive neuroectodermal tumour are presented. In a 32-year-old man, the tumour evolved intradurally from a sacral nerve root. Despite repeated surgery and radiochemotherapy, the patient suffered multiple intraspinal tumour relapses and intracranial seedings, and died 29 months after the first diagnosis. In a 17-year-old male adolescent, the tumour was located in the lumbar epidural space, extending into the paraspinal muscles. Following resection and radiochemotherapy, the patient is free from disease 23 months after the initial presentation. The clinical, radiological, histopathological and cytogenetic findings of both patients are presented and the relevant literature is reviewed. Particular attention is given to the histogenetic relationship between peripheral primitive neuroectodermal tumour and Ewing's sarcoma.

Adolescent↗
PubMed2005

Malignant non-teratoid medulloepithelioma with submandibular metastases.

Medulloepithelioma is a tumor of the primitive medullary epithelium overlying the ciliary body. Most become evident early in life, and they may be malignant, although distant metastases are rare. The purpose of this report is to describe a malignant nonteratoid neoplasm and its metastasis to the submandibular lymph nodes and to introduce this uncommon neoplasm with otolaryngologists.

Adolescent↗
PubMedDate not supplied

Immunocytochemical detection of the homeobox B3, B4, and C6 gene products in childhood medulloblastomas/primitive neuroectodermal tumors.

The homeobox was originally described as a conserved DNA motif of about 180 base pairs. The protein domain encoded by the homeobox, the homeodomain, is thus about 60 amino acids long. The homeodomain is a DNA-binding domain, and many homeobox genes have now been shown to bind to DNA and regulate the transcription of other genes. Thus homeodomain proteins are basically transcription factors, most of which play a role in development. The homeobox genes seem to represent another class of oncofetal antigens involved in both normal development and carcinogenesis, as well as tumor progression. It has been shown that HOX-B3 and HOX-B4 are preferentially expressed in primitive CD34+, lineage-committed hematopoietic stem cells (HSCs) in human bone marrow. HOX-B3 overexpression in HSCs causes defective lymphoid development and progressive myeloproliferation, while HOX-B4 leads to selective expansion of HSCs without altering their differentiation. The HOX-C6 gene product leads to cell differentiation in neuroblastomas, while also being associated with the neoplastically transformed mammary cell phenotype and progression in primary cutaneous lymphomas. The expression pattern of these three homeobox gene products (HOX-B3, HOX-B4, and HOX-C6) was examined immunocytochemically in childhood MEDs/PNETs employing an indirect alkaline phosphatase conjugated technique on formalin-fixed, paraffin-embedded tissue sections. Strong staining intensity (A, B) of HOX-B3 and HOX-B4 was registered in all MEDs/PNETs, with immunoreactivity in between 50% and 90% (+3), but usually over 90% (+4) of the tumor cells. HOX-C6 was detected at medium intensity (mostly B) in 50% to 90% (+3) of the MED/PNET cells. This report is the first to describe the expression of these three homeobox gene products in MEDs/PNETs, and provides further evidence for the role of these proteins in the progression of human malignancies. The value of these genes and proteins in the early diagnosis and possible treatment of various human neoplasms, including childhood brain tumors, should be assessed in further immunocytochemical and molecular biological experiments.

Adolescent↗
PubMedDate not supplied

Atypical neuronal-glial tumors of cerebral hemispheres in adults with PNET-like component: clinicopathological features of 5 cases.

We investigated 5 cases with brain tumors composed ofneuronal and astrocytic differentiated tumor cells occurring in the cerebral hemispheres of adults. Patients ranged from 33 - 69 years of age, 3 females and 2 males. Radiologically, contrast enhancement was demonstrated in these tumors. All tumors were surgically resected following radiotherapy and chemotherapy. Four patients have been free of recurrence for 2-5 years. One recurred 15 years after the operation. Histologically, tumor cells were mainly composed of round or oval nucleate cells with scant cytoplasm and compactly arranged with neurocytic features. Immunohistochemically, some tumor cells were immunoreactive for synaptophysin, neurofilament, beta-tubulin, chromogranin A, GFAP and vimentin. There were little immunoreactive cells for myelin basic protein and epithelial membrane antigen. Ultrastructurally, tumor cells were variably differentiated as follows: undifferentiated cells having prominent nuclei and scanty cytoplasm with inconspicuous organelles; neuronal cells consisting of neurosecretory granules or vesicles and abortive synapses, and astrocytic cells with cytoplasmic intermediate filaments. The Ki-67 labeling index ranged from 4.5 - 9.8%. Allelic loss of chromosome Ip occurred in 2 cases (50%) and allelic loss of chromosome 19q occurred in 2 cases (50%) of 4 informative cases. These tumors were characterized as neuronal and astrocytic differentiated tumors with primitive PNET-like component. However, there was little oligodendrocytic or ependymal differentiation in these tumors.

Adult↗