Disease relevance of Neurilemmoma

• Carney complex (CNC) is a multiple neoplasia syndrome characterized by spotty skin pigmentation, cardiac and other myxomas, endocrine tumours and psammomatous melanotic schwannomas [1].
• Increased proteolysis of merlin by calpain in some schwannomas and meningiomas exemplifies tumorigenesis linked to the calpain-mediated proteolytic pathway [2].
• GFA and S 100 protein levels as an index for malignancy in human gliomas and neurinomas [3].
• Neuroectodermal cell lines used as illustrative examples included subclones of the C6 astrocytoma and of the RN-2 schwannoma [4].
• None of the fibrosarcomas, malignant schwannomas, and liposarcomas examined had mutated TP53 [5].

High impact information on Neurilemmoma

• Neurofibromatosis type 2 is an autosomal dominant disorder characterized by tumors, predominantly schwannomas, in the nervous system [6].
• Adenosine 3',5'-monophosphate analogs promote a circular morphology of cultured Schwannoma cells [7].
• The Vectstain avidin-biotin-peroxidase complex immunoperoxidase staining procedure for S-100 protein revealed that the S-100 protein existed in an ependymoblastoma and in areas of typical nuclear palisading in a malignant schwannoma in coho salmon [8].
• Genetics of susceptibility of rats to trigeminal schwannomas induced by neonatal administration of N-ethyl-N-nitrosourea [9].
• Similarly, the more malignant a neurinoma was, the lower was its S 100 protein content [3].

Chemical compound and disease context of Neurilemmoma

• Sequential development of ethylnitrosourea-induced neurinomas: morphology, biochemistry, and transplantability [10].
• Effect of levamisole on malignant experimental neurinoma grown subcutaneously in a young rat: brief communication [11].
• Polyacrylamide gels of antilaminin immunoprecipitates of conditioned medium and solubilized Schwannoma cells contained bands of reduced Mr 200,000 and 150,000 [12].
• We show enhanced adhesion in primary human schwannoma cells and present evidence that this is dependent on the integrin chains alpha6beta1 and alpha6beta4 [13].
• Rat RN22 schwannoma cells in vitro release into their growth medium a macromolecular factor that, when bound to polyornithine-coated culture substrata, will stimulate neuritic regeneration from axotomized peripheral and central neurons [14].

Biological context of Neurilemmoma

• We tested whether this mechanism may also apply for the neurofibromatosis type-2 gene (NF2) which, when mutated, leads to schwannoma development [15].
• Patients with multiple schwannomas without vestibular schwannomas have been postulated to compose a distinct subclass of neurofibromatosis (NF), termed "schwannomatosis." To compare the molecular-genetic basis of schwannomatosis with NF2, we examined the NF2 locus in 20 unrelated schwannomatosis patients and their affected relatives [16].
• Upregulation of the Rac1/JNK signaling pathway in primary human schwannoma cells [17].
• We also find that schwannomin inhibits Stat3 and Stat5 phosphorylation in the rat schwannoma cell line RT4 [18].
• Exon scanning for mutation of the NF2 gene in schwannomas [19].

Anatomical context of Neurilemmoma

• Tumor cell lines derived from malignant schwannomas removed from patients with neurofibromatosis type 1 (NF1) have been examined for the level of expression of NF1 protein [20].
• Non-neuronal drg cells obtained by a procedure designed for the preparation of pure Schwann cells, as well as RN6 Schwannoma cells, were beta NGF receptor positive [21].
• Schwannoma-derived growth factor (SDGF) was initially isolated from schwannoma cells as a mitogen for glial cells and fibroblasts [22].
• Among these factors are bona fide growth factors such as Fibroblast Growth Factor-1 and -2 and Schwannoma Derived Growth Factor, for which internalization and nuclear translocation have been demonstrated [23].
• Similarly, tissue-specific ablation of Prkar1a from a subset of facial neural crest cells caused the formation of schwannomas with divergent differentiation [24].

Gene context of Neurilemmoma

• We demonstrate that regulated overexpression of HRS in rat schwannoma cells results in similar effects as overexpression of merlin, including growth inhibition, decreased motility and abnormalities in cell spreading [25].
• Prkar1a(+/-) mice developed nonpigmented schwannomas and fibro-osseous bone lesions beginning at approximately 6 months of age [24].
• In contrast, PCNA is more highly expressed in cellular schwannomas [26].
• Neuregulin growth factors and their ErbB receptors form a potential signaling network for schwannoma tumorigenesis [27].
• Rearrangements of the intermediate filament GFAP in primary human schwannoma cells [28].

Analytical, diagnostic and therapeutic context of Neurilemmoma

• Western blotting with antibodies directed against ezrin, radixin, and moesin, however, showed expression of these proteins in all schwannomas [29].
• Western blotting and immunohistochemistry with antibodies directed against the amino and carboxy termini of merlin demonstrated loss of merlin expression in all studied schwannomas, including 12 tumors lacking genetic evidence of biallelic NF2 gene inactivation [29].
• Gene therapy for schwannomas was evaluated in two mouse models of neurofibromatosis type 2 (NF2): (1) a transgenic model in which mice express a dominant mutant form of merlin and spontaneously develop schwannomas, and (2) a xenograft model in which human schwannoma tissue is implanted subcutaneously into immune- compromised mice [30].
• Apolipoprotein E is expressed in neurofibrosarcoma and Schwannoma cell cultures derived from two patients with different types of neurofibromatosis, but not in six cell cultures derived from the benign neurofibromatosis neurofibromas [31].
• The level and number of CYP2E1 gene transcripts were investigated by northern blot analysis in various human adult tissues including liver, lung, placenta, skin and neurinoma [32].

References