Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The desmoplastic cerebral astrocytoma of infancy (DCAI) is a rare tumor that presents as a large hemispheric mass in infants. Despite an ominous histologic picture that may resemble a sarcoma, the tumor is astrocytic and has a good prognosis. We present two cases of DCAI, with histopathologic, immunohistochemical, ultrastructural, and molecular genetic data, and draw the following conclusions: (1) the diagnosis of DCAI requires a high index of suspicion and immunohistochemical or ultrastructural proof of astrocytic differentiation; (2) the data argue against nosologically equating these tumors with the desmoplastic infantile ganglioglioma, pleomorphic xanthoastrocytoma, or gliofibroma; (3) the components of the extensive tumor basal lamina may be elaborated by the tumor cells themselves and may contribute in an autocrine fashion to the slow growth of these lesions; and (4) if the lack of allelic loss on chromosomes 17p (including the p53 tumor suppressor gene locus) and 10 seen in our cases is found in other cases of DCAI, this may further distinguish the DCAI from other astrocytomas.
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PMID:Desmoplastic cerebral astrocytomas of infancy: a histopathologic, immunohistochemical, ultrastructural, and molecular genetic study. 146 78

Gangliogliomas are tumors composed of intimately admixed neuronal and glial components and account for approximately 1% of all brain tumors. Here we report the histopathological findings in 61 gangliogliomas. Epilepsy was the most common presenting symptom. Most gangliogliomas were located in the temporal lobes (74%). Thirteen percent of the gangliogliomas were associated with glioneuronal hamartias. There was considerable variation in neuronal size and density, presence of binucleated neurons, calcifications, desmoplasia, lymphocytic infiltrate, pilocytic differentiation, Rosenthal fibers, location, or histological uniformity. Fifteen percent of the gangliogliomas contained areas of purely astrocytic differentiation. All tumors were examined immunohistochemically for an aberrant p53 tumor suppressor gene product and for the presence of nuclear antigens associated with cell proliferation (Ki-67, Ki-S1, proliferating cell nuclear antigen). In 45 of 61 cases (74%) labeling indices for Ki-67 were less than 1%. Nuclear labeling for Ki-67 was observed exclusively in the astrocytic component. Gangliogliomas with very large neurons had higher Ki-67 labeling indices and occurred in younger patients than gangliogliomas with small- or intermediate-sized neurons. None of the tumors had an aberrant expression of p53. The observations suggest that gangliogliomas may arise from glioneuronal hamartias through neoplastic transformation of the astrocytic component.
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PMID:Ganglioglioma: a detailed histopathological and immunohistochemical analysis of 61 cases. 798 97

Gliofibromas are rarely encountered astrocytic neoplasms characterized by an admixture of astrocytic and fibroblastic cell components. The exact nature of these rare tumors are still a matter of considerable debate. This article reports a case of gliofibroma occurring in a 3-month-old boy. The astrocytic component of the tumor stained diffusely positive for glial fibrillary acidic protein (GFAP) and S-100 protein. Prominent reticulin staining was observed within the fibroblastic component of the tumor. The MIB1 labeling index (positive number of tumor cells divided by total tumor cells counted X 100) was low (0.9), supporting the general slow growth of these tumors. Immunohistochemical staining with antibody against p53 protein was negative. Gliofibromas seem to be a low-grade variant of an astrocytoma that shares many features with other desmoplastic astrocytic neoplasms (desmoplastic infantile astrocytoma, desmoplastic infantile ganglioglioma) including a generally favorable prognosis.
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PMID:Gliofibroma: a distinct entity or a subtype of desmoplastic astrocytoma? 866 74

We studied two cases of ganglioglioma immunohistochemically by MIB-1 and p53 staining. The positive rate of MIB-1 in the ganglionic cells was 5.5% in Case 1 and 7.8% in Case 2, and that of MIB-1 in the gliomatous cells was 1.4 and 6.6% respectively. The labeling index of p53 in the ganglionic cells was 7.3% in Case 1 and 7.7% in Case 2, and that of the gliomatous cells was 1.9 and 3.4% respectively. MIB-1 and p53 did not stain ganglionic precursor cells. These results indicate that the ganglionic cells also take part in proliferation and have potential of malignant transformation.
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PMID:Proliferative potential and malignant transformation of ganglioglioma: immunohistochemical studies by MIB-1 and p53 staining. 886 95

A gangliocytoma/ganglioglioma with no atypical or malignant features was subtotally resected from the right temporal lobe of a 16-year-old woman. A second resection was performed 8 years later to treat a locally recurrent lesion with increased cellularity that was diagnosed as a World Health Organization Grade II ganglioglioma on the basis of neuropathological examination. Molecular analysis of the recurrent tumor revealed a TP53 gene mutation, but no amplification of the epidermal growth factor receptor (EGFR) gene. Radiotherapy (60 Gy) was administered after the second resection. The patient returned 1 year later with a second focal recurrence. The specimen obtained during the third resection of tumor exhibited exclusively astrocytic differentiation, cellular pleomorphism with multinucleated cells, high mitotic activity, and endothelial proliferation. Therefore, the tumor was diagnosed to be a glioblastoma multiforme (GBM). Molecular analysis of tumor DNA from the second recurrent tumor demonstrated the presence of the TP53 mutation, which previously had been observed in the first recurrent tumor, but again no evidence of EGFR amplification. Findings demonstrate that the presence of TP53 mutation in progressed gangliogliomas should be interpreted as a progression-associated mutation rather than a consequence of treatment. This is the first report to indicate that the molecular pathways of gangliocytomas/gangliogliomas progressing to become GBMs may parallel those of diffuse astrocytomas progressing to become GBMs.
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PMID:Malignant transformation of a gangliocytoma/ganglioglioma into a glioblastoma multiforme: a molecular genetic analysis. Case report. 1145 85

The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59-year-old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB-1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB-1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double-positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10).
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PMID:Anaplastic ganglioglioma with sarcomatous component: an immunohistochemical study and molecular analysis of p53 tumor suppressor gene. 1203 Apr 14

In the present study the clinical data, histology, proliferation rate, DNA ploidy status and the results of TP53 mutation analysis and comparative genomic hybridization (CGH) of three typical cases of desmoplastic infantile astrocytoma and ganglioglioma are presented. Postoperative disease-free intervals of 11, 8 and 3 years were recorded and in none of the cases were radiological signs of tumor recurrence. No TP53 mutations (exons 5-8) were found. CGH analysis revealed loss of 8p22-pter in one case, while in another case gain of 13q21 was detected. In the case with the follow-up of 11 years an aneuploid DNA-flow cytogram along with slightly increased MIB-1 labeling index (LI) was found. The results demonstrate little genetic instability in these low-grade lesions. DNA-aneuploidy seems not to be indicative of tumor progression. It is concluded that the genetic aberrations found in desmoplastic infantile ganglioglioma differ from those encountered in common astrocytomas.
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PMID:Desmoplastic infantile astrocytoma and ganglioglioma: a search for genomic characteristics. 1211 57

Gangliogliomas generally behave as benign indolent tumors. However, gangliogliomas undergoing malignant transformation have also been reported. The molecular basis for the malignant transformation of gangliogliomas remains unclear. We describe a case of ganglioglioma, which had transformed to glioblastoma after the gross total resection of the original tumor, in a 4-year-old girl. The present case is unusual in four aspects: (i) it arose from a low-grade ganglioglioma in the absence of previous radiation or chemotherapy, which is the fourth reported case; (ii) the original tumor showed a high proliferative index on flow cytometry but a low Ki-67 labeling index, implying that the application of flow cytometry might play a certain role in predicting biological and clinical behavior of low grade gangliogliomas; (iii) p53 mutation and deletion appeared in the secondary glioblastoma, which was not shown in the original well-differentiated ganglioglioma; and (iv) the transformed glioblastoma showed p16 inactivation detected by methylation and deletion, which are relatively uncommon genetic events in secondary glioblastomas. This is the first report of a genetic alteration in glioblastoma arising from a well differentiated ganglioglioma prior to radiation or chemotherapy. Based on the above findings, irrespective of radiotherapy or chemotherapy, rare recurrence of malignant evolution, especially tumors of high S-phase fraction on flow cytometry, warrants long-term follow-up, even in a well-differentiated ganglioglioma.
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PMID:Glioblastomatous transformation of ganglioglioma: case report with reference to molecular genetic and flow cytometric analysis. 1462 54

Sclerosing meningioma is a distinct histologic subtype of meningioma, however, it is often confused with other tumors, especially malignant tumors. To widen our knowledge of sclerosing meningioma and to help neurosurgeons and neuropathologists diagnose this clinically and pathologically unfamiliar disease entity, we reviewed four such cases, which were originally misdiagnosed. Sclerosing meningiomas were assessed for cellularity, cellular pleomorphism, mitotic activity, brain invasion, and necrosis. Immunohistochemical staining was performed on paraffin-embedded sections using the avidin-biotin-peroxidase complex method. The histologic appearance of the underlying cerebral parenchyma invasion by tumor cells led to a diagnosis of malignant meningioma or to the completely erroneous diagnosis of ganglioglioma. The most conspicuous histologic finding of these four sclerosing meningiomas was extensive collagen deposition, so called 'sclerosis' and an intermingled small population of spindle or round cells with clear cytoplasmic halos, giving a 'fried egg' appearance. However, a typical meningothelial whorl pattern was identified in all cases. Tumor cells exhibited positive immunoreactivity for epithelial membrane antigen and vimentin, but were negative for glial fibrillary acidic protein, p53, S-100, and neuronal markers. Proliferative indices, using Ki-67, ranged from 0% to 4%, and brain invasion was present in three of four tumors. All four patients are doing well with no evidence of tumor recurrence (follow-up duration of 25 months to 12 years). Brain invasion needs to be re-evaluated as a criterion of malignancy in meningioma. Special attention should be paid to the diagnosis of this subtype of meningioma to prevent unnecessary postoperative radiotherapy and to ensure correct therapeutic decision.
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PMID:Sclerosing meningioma: clinicopathological study of four cases. 1521 54

Gangliogliomas are characterized by their different phenotypic composition of ganglion cells and glial cells. In contrast to the glial cells that are capable of mitotic activity, the ganglion cells are generally considered to lack a neoplastic nature. The authors report here the first unequivocal case of a ganglioglioma harboring aberrant TP53 product that was expressed predominantly in the neuronal component. GeneChip TP53 assay revealed a point mutation resulting in an exchange of amino acid. This case suggests that ganglion cells can participate in the neoplastic process of gangliogliomas.
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PMID:Aberrant TP53 protein accumulation in the neuronal component of ganglioglioma. 1592 88


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