Diensthuber M, Lenarz T, Stöver T
Klinik und Poliklinik für Hals-Nasen-Ohrenheilkunde, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, 30625 Hannover.
Laryngorhinootologie. 2006 Oct;85(10):731-7. doi: 10.1055/s-2006-925286. Epub 2006 Apr 10.
The vestibular schwannoma is a benign, slow-growing neoplasm that originates from the neurolemmal sheath of the vestibular branch of the VIIIth cranial nerve. This tumor entity accounts for 6 % of all intracranial tumors and the annual incidence of newly diagnosed vestibular schwannoma is reported as 13 per million. The molecular pathogenesis of both sporadic vestibular schwannoma and those occurring in neurofibromatosis type II appears to be associated with an aberration of a tumor suppressor gene on chromosome 22q12. The biological background for the various growth patterns of vestibular schwannoma is, however, largely unknown. This differing clinical and biological behaviour of vestibular schwannoma may be explained by the presence of neurotrophic factors. The results of recent immunohistochemical studies demonstrate the co-expression of transforming growth factor (TGF)-beta 1 and glial cell line-derived neurotrophic factor (GDNF) in vestibular schwannoma and suggest a trophic synergism of both neurotrophic factors in this tumor. Moreover, expression of numerous different neurotrophic factors has been shown in studies of nerve growth factor (NGF), vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), fibroblast growth factor (FGF), neuregulin (NRG) and erythropoietin (EPO) indicating a biological role in development, maintainance or growth of vestibular schwannoma. In this article, we summarize the findings on neurotrophic factor expression and discuss their characteristics and biological role in vestibular schwannoma.
前庭神经鞘瘤是一种良性、生长缓慢的肿瘤，起源于第八对脑神经前庭支的神经膜鞘。该肿瘤实体占所有颅内肿瘤的6%，据报道，新诊断的前庭神经鞘瘤的年发病率为百万分之十三。散发性前庭神经鞘瘤和II型神经纤维瘤病中出现的前庭神经鞘瘤的分子发病机制似乎都与22q12染色体上肿瘤抑制基因的畸变有关。然而，前庭神经鞘瘤各种生长模式的生物学背景在很大程度上尚不清楚。前庭神经鞘瘤这种不同的临床和生物学行为可能由神经营养因子的存在来解释。最近免疫组织化学研究的结果表明，转化生长因子（TGF）-β1和胶质细胞源性神经营养因子（GDNF）在前庭神经鞘瘤中共同表达，并提示这两种神经营养因子在该肿瘤中存在营养协同作用。此外，在神经生长因子（NGF）、血管内皮生长因子（VEGF）、表皮生长因子（EGF）、成纤维细胞生长因子（FGF）、神经调节蛋白（NRG）和促红细胞生成素（EPO）的研究中已显示出许多不同神经营养因子的表达，表明它们在前庭神经鞘瘤的发生、维持或生长中具有生物学作用。在本文中，我们总结了神经营养因子表达的研究结果，并讨论了它们在前庭神经鞘瘤中的特征和生物学作用。
