|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
Mutations of the p53 tumor suppressor gene are a genetic hallmark of human astrocytic neoplasms, but their predictive role in glioma progression is still poorly understood.
|
9815715 |
1997 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
Wild-type p53 failed to sensitize glioma cells to cytotoxic drugs including BCNU, cytarabine, doxorubicin, teniposide and vincristine.
|
9760067 |
1998 |
|
Glioma
|
0.900 |
AlteredExpression
|
disease |
BEFREE |
Sequencing analysis demonstrated that a human glioma cell line (U-373MG) had only a class I mutant form of p53 of His273, which targets an Arg273 that contacts DNA but retains the native structure.
|
10328543 |
1998 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
The frequency of mutations within glioma-associated TSG, such as TP53 and RB, suggests that defects in TGFbeta's inhibitory signaling pathway may have analogous effects in the progression to HD-GM, and TGFbeta's conversion to a mitogen.
|
9525812 |
1998 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
Transfection of a vector expressing wild-type p53 into cells of two human glioma cell lines enhances radiation toxicity.
|
9650599 |
1998 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
The induction of p53 protein in glioma cell lines that overexpress wild-type p53 differs from normal control cells and glioma cell lines containing mutant p53.
|
9664113 |
1998 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
Comparisons were made to the glioma cell line U251MG, which contains a mutant p53 allele.
|
9647183 |
1998 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
In order to dissect (i) specific effects of wild-type versus mutant p53, and (ii) transdominant-negative versus gain-of-function effects of mutant p53, we included glioma cell lines with functional wild-type (LN-229), mutant (LN-18) or deleted (LN-308) p53 genes.
|
10352342 |
1999 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
Six constitutional missense mutations of the p53 gene were identified (13.6%), but no mutations of the p16 and PTEN genes were found, suggesting that (1) germline p53 mutations contribute to a small portion of astrocytic tumors, (2) inherited mutations of the p16 and PTEN gene do not predispose to the development of gliomas, and (3) other genes are involved in glioma predisposition.
|
10589545 |
1999 |
|
Glioma
|
0.900 |
AlteredExpression
|
disease |
BEFREE |
We have previously shown that massive apoptosis occurs when wild-type p53 or E2F-1 expression is induced in glioma.
|
9864390 |
1999 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
Neither baseline p27 levels nor p27 levels induced by confluency or serum deprivation correlate with p53 status or drug sensitivity of human glioma cell lines.
|
10441521 |
1999 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
Although mutation or inactivation of the p53 tumor suppressor gene occurs at early stages in gliomas and is associated with tumor progression, many tumors including high-grade glioblastoma multiforme carry a functionally intact p53 gene.
|
10100717 |
1999 |
|
Glioma
|
0.900 |
AlteredExpression
|
disease |
BEFREE |
The ability to enhance the radiosensitivity of malignant glioma cells that express wild-type p53 by using adenoviral transduction to induce overexpression of p53 offers hope for this approach as a therapeutic strategy, not only in human gliomas that express mutant p53, but also in those that express wild-type p53.
|
10584846 |
1999 |
|
Glioma
|
0.900 |
AlteredExpression
|
disease |
BEFREE |
In contrast, the lines that had mutant, nonfunctional P53 did not undergo spontaneous apoptosis, but they were rendered more sensitive to the apoptosis-inducing effect of ara-C. Modulation of BAX expression may be a useful therapeutic modality for gliomas, regardless of p53 genotype.
|
10470825 |
1999 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
Growth inhibition and apoptosis were independent of the endogenous p53 status of the glioma cell lines.
|
10200333 |
1999 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
Radioresistance was acquired when p21 was overproduced in the glioma cell lines irrespective of p53 status.
|
10429656 |
1999 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
This indicates that the gene(s) on the 17p13.3 region of the human chromosome may be influencing the p53 immunopositivity status of glial tumors and possibly other tumors in general.
|
10840825 |
2000 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
We analysed p53 and p14arf in relation with five other genetic loci encoding the most frequently mutated genes in human gliomas: cdkn2a, mdm2, egfr, pten and the chromosomal regions 10q23.3 and 10q25-26.
|
10949938 |
2000 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
To override the resistance mechanism of glioma cells with p53 mutation to radiation, we transduced U-373MG malignant astrocytoma (glioma) cells harboring mutant p53 with Fas ligand via an adenovirus (Adv) vector in combination with X-ray irradiation, and evaluated the degree of apoptosis.
|
11050476 |
2000 |
|
Glioma
|
0.900 |
PosttranslationalModification
|
disease |
BEFREE |
These results suggest that mutation of the PTEN gene is a later event than that of the p53 gene in glioma progression and is associated with both the genetic pathways.
|
11051241 |
2000 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
Here, we assessed the expression levels of GST-pi and GST-mu RNA and protein as well as total GST activity in a panel of 12 human glioma cell lines and correlated these data with p53 status, BCL-2 family protein expression and drug sensitivity in these cells.
|
11054494 |
2000 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
A human glioma cell line (U-87MG) that expresses wild-type p53, one that expresses mutant p53 (T-98G), and a T-98G derivative (T-98G/p53) that was transfected with a wild-type p53 expression vector (pCDM8-p53/neo) were used.
|
10930016 |
2000 |
|
Glioma
|
0.900 |
GeneticVariation
|
disease |
BEFREE |
Thus, whereas germ-line mutations of PTEN, p53, p16(INK4A)/p14(ARF), and CDK4 are not common events in familial glioma, outside of familial cancer syndromes, point mutations of p53 and hemizygous deletions and other rearrangements of the p16(INK4A)/p14(ARF) tumor suppressor region may account for a subset of familial glioma cases.
|
10797439 |
2000 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
Virus producing single cell clone GP+envAm12/ p53clC8 (8 x 10(5) cfu/ml, determined on NIH 3T3 cells) was isolated and used to transfer wt-p53 gene into human glioma cell lines in vitro.
|
11043823 |
2000 |
|
Glioma
|
0.900 |
Biomarker
|
disease |
BEFREE |
The p53 status of the four human glioma cell lines tested was not a predictor for either their relative sensitivity to ionizing radiation or ability to be protected by WR-1065.
|
10866285 |
2000 |