Wang Lei, Sun Moyi, Jiang Yuegui, Yang Lianjia, Lei Delin, Lu Chao, Zhao Yinghua, Zhang Pu, Yang Yaowu, Li Jianhu
Department of Oral and Maxillofacial Surgery, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China.
J Oral Maxillofac Surg. 2006 Apr;64(4):636-41. doi: 10.1016/j.joms.2005.12.011.
Perineural invasion is a frequent occurrence in salivary adenoid cystic carcinoma (ACC) and may prevent complete surgical resection. Studies have indicated that nerve growth factor (NGF) and its high-affinity receptor tyrosine kinase A (TrkA) may play a role in perineural invasion in several malignancies in which perineural invasion is observed. The present study was conducted to investigate the expression of NGF and TrkA in salivary ACC and to examine the effects of NGF on adhesion, migration and invasion capacities of a salivary ACC cell line (SACC-83) in vitro.
Expression of NGF and TrkA was explored using immunohistochemistry in paraffin-embedded tissues of 32 cases of salivary ACC. The effects of NGF on in vitro adhesion, migration, and invasion capacities of the SACC-83 cell line were examined using an MTT assay and a modified Boyden chamber assay respectively.
In ACC specimens, 31 (96.9%) and 32 (100%) tumors showed immunoreactivity for NGF and TrkA respectively. Significant correlations were found between NGF/TrkA expression levels and perineural invasion (P < .05). In cell adhesion assay, the percent adherences of SACC-83 cells co-cultured with 25 ng/ml NGF at 1.5 hours and 5, 25 ng/ml NGF at 6 hours were significantly higher than that co-cultured with 0 ng/ml NGF (P < .05). However, high concentration of NGF (500 ng/ml) resulted in a significant inhibition of invasion (P < .05).
Overexpression of NGF and TrkA in human salivary ACC tissues may constitute a reason for perineural invasion in salivary ACC.
神经周围浸润在涎腺腺样囊性癌（ACC）中很常见，可能会妨碍手术完全切除。研究表明，神经生长因子（NGF）及其高亲和力受体酪氨酸激酶A（TrkA）可能在几种观察到神经周围浸润的恶性肿瘤的神经周围浸润中起作用。本研究旨在调查NGF和TrkA在涎腺ACC中的表达，并检测NGF对涎腺ACC细胞系（SACC-83）体外黏附、迁移和侵袭能力的影响。
采用免疫组织化学方法检测32例涎腺ACC石蜡包埋组织中NGF和TrkA的表达。分别采用MTT法和改良的Boyden小室法检测NGF对SACC-83细胞系体外黏附、迁移和侵袭能力的影响。
在ACC标本中，分别有31例（96.9%）和32例（100%）肿瘤对NGF和TrkA呈免疫反应性。发现NGF/TrkA表达水平与神经周围浸润之间存在显著相关性（P < 0.05）。在细胞黏附试验中，与25 ng/ml NGF共培养1.5小时以及与5、25 ng/ml NGF共培养6小时的SACC-83细胞的黏附百分比显著高于与0 ng/ml NGF共培养的细胞（P < 0.05）。然而，高浓度的NGF（500 ng/ml）导致侵袭显著受到抑制（P < 0.05）。
人涎腺ACC组织中NGF和TrkA的过表达可能是涎腺ACC发生神经周围浸润的一个原因。
