|
neurofibroma
|
0.500 |
Biomarker
|
disease |
BEFREE |
Somatic inactivation of the Nf1 tumor suppressor gene, which encodes neurofibromin, is necessary but not sufficient to initiate neurofibroma development.
|
16648142 |
2006 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
Our patient's neurofibromas were secondary to a postzygotic mutation in the NF-1 gene of neural crest-derived cells.
|
15868313 |
2006 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
To the best of our knowledge, this represents the first demonstration of a somatic biallelic inactivation of the NF1 gene in neurofibroma, providing further evidence for the importance of NF1 inactivation also in sporadic neurofibromas.
|
15986446 |
2005 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
If we assume that dual-color FISH analysis is sensitive enough to detect the majority of large somatic deletions present, then other mutational mechanisms affecting the NF1 gene are probably involved in neurofibroma formation, and other tumor suppressor genes may play an important role in NF1 tumorigenesis.
|
15066327 |
2004 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
Duplicon-mediated microdeletions around the NF1 gene are frequently associated with a severe form of neurofibromatosis type I in a subgroup of patients who show an earlier onset of cutaneous neurofibromas, dysmorphic facial features, and lower IQ values.
|
12696059 |
2003 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
The analysis of somatic NF1 gene mutations in neurofibromas from NF1 patients revealed that each neurofibroma results from an individual second hit mutation, indicating that factors that influence somatic mutation rates may be regarded as potential modifiers of NF1.
|
14635100 |
2003 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
LHGDN |
NF1 mutations and clinical spectrum in patients with spinal neurofibromas.
|
12746402 |
2003 |
|
neurofibroma
|
0.500 |
AlteredExpression
|
disease |
BEFREE |
Neurofibromin was not expressed in Schwann cells and sustentacular cells of composite pheochromocytomas and was very weakly or negatively expressed in neurofibroma of NF1 patients.
|
11904334 |
2002 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
We describe here a patient with segmental NF in which we could not demonstrate any NF1 gene mutation in fibroblasts cultured from neurofibromas by use of the protein truncation test, enzymatic mutation detection and fluorescence in situ hybridisation.
|
12077526 |
2002 |
|
neurofibroma
|
0.500 |
Biomarker
|
disease |
BEFREE |
Deletion of both copies of the Nf1 gene in Schwann cells combined with Nf1 heterozygosity in the tumor environment promotes neurofibroma formation in mice.
|
12124168 |
2002 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
Somatic point mutations or the presence of "two hits" in the NF1 gene have only been reported for a few neurofibromas.
|
11409870 |
2001 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
A total loss of the NF1 gene product by stochastic events inactivating the wild type allele in Schwann cells should precede the development of neurofibromas.
|
11701400 |
2001 |
|
neurofibroma
|
0.500 |
Biomarker
|
disease |
BEFREE |
Since the NF1 gene is supposed to be a tumour suppressor gene, these neurofibromas should develop upon inactivation of both NF1 alleles.
|
11175282 |
2000 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
Recent evidence demonstrates that somatic mutations at the NF1 gene are found in neurofibromas, but it has not been demonstrated whether SCs, fibroblasts and/or both cell types bear a somatic loss of NF1.
|
11115850 |
2000 |
|
neurofibroma
|
0.500 |
AlteredExpression
|
disease |
BEFREE |
Our results suggest that small subtle mutations occur with similar frequency to that of LOH in benign neurofibromas and that somatic inactivation of the NF1 gene is a general event in these tumors.
|
10677298 |
2000 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
However, since all other CpG sites were unmethylated in all tissues examined, it is unlikely that CpG hypermethylation within the NF1 promoter represents a common mutational mechanism leading to neurofibroma formation.
|
10982032 |
2000 |
|
neurofibroma
|
0.500 |
AlteredExpression
|
disease |
BEFREE |
EVI2B, a gene lying in an intron of the neurofibromatosis type 1 (NF1) gene, is as the NF1 gene involved in differentiation of melanocytes and keratinocytes and is overexpressed in cells derived from NF1 neurofibromas.
|
10360836 |
1999 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
This result suggests that genetic alterations of the NF1 gene in Schwann cells are responsible for the development of neurofibromas.
|
10451710 |
1999 |
|
neurofibroma
|
0.500 |
AlteredExpression
|
disease |
BEFREE |
Therefore, the recent reports mentioned above, together with our findings, strongly support the double inactivation of the NF1 gene in benign neurofibromas.
|
9326316 |
1997 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
Two tumor types that have been linked to specific gene alterations are schwannomas, which have mutations in the neurofibromatosis (NF) type 2 (NF2) gene, and neurofibromas, which characteristically possess NF type 1 (NF1) gene mutations.
|
9354454 |
1997 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
Clonal origin of tumor cells in a plexiform neurofibroma with LOH in NF1 intron 38 and in dermal neurofibromas without LOH of the NF1 gene.
|
9177273 |
1997 |
|
neurofibroma
|
0.500 |
AlteredExpression
|
disease |
BEFREE |
To explain the observation that transgenic mice expressing the human T-lymphotropic virus type 1 (HTLV-1) tax gene under the control of the viral regulatory element also develop multiple neurofibromas, we demonstrate that the Tax trans-regulator can functionally repress NF1 gene expression through a cis-acting element located immediately upstream of its transcriptional start site, thereby allowing the development of benign neurofibromas without the need for direct mutations in NF1.
|
8627811 |
1996 |
|
neurofibroma
|
0.500 |
AlteredExpression
|
disease |
BEFREE |
The molecular basis of neurofibroma development in NF1 is loss of expression of the NF1 gene and its gene product, neurofibromin, resulting in elevated levels of Ras-guanosine triphosphate.
|
8622163 |
1996 |
|
neurofibroma
|
0.500 |
GeneticVariation
|
disease |
BEFREE |
Single-cell PCR performed with neurofibroma Schwann cells reveals the presence of both alleles of the neurofibromatosis type 1 (NF1) gene.
|
8530015 |
1995 |
|
neurofibroma
|
0.500 |
Biomarker
|
disease |
BEFREE |
Western blot analysis demonstrated deficiency of neurofibromin in the tumours derived from three out of the four neurofibromatosis type 1 patients: a fibrolipoma, a malignant schwannoma and a neurofibroma.
|
7614817 |
1995 |