Yuan Yulin, Zhou Xuhong, Song Jian, Qiu Xiaoping, Li Jun, Ye Linfeng, Meng Xiaoping, Xia Dong
Department of Anatomy, Wuhan University School of Medicine, Hubei, People's Republic of China.
Ann Otol Rhinol Laryngol. 2008 Mar;117(3):192-200. doi: 10.1177/000348940811700306.
Epidermal growth factor (EGF) and type 1 insulin-like growth factor (IGF-1) receptors play an important role in the growth and apoptosis of nasopharyngeal carcinoma (NPC). They were separately found to be associated with prognosis in patients with NPC. To date, their expression correlation and clinicopathologic significance have never been specifically addressed in NPC.
Seventy-five patients with NPC and 21 noncancerous nasopharyngeal epithelial samples were accrued between 1998 and 2006 in a single hospital. The expressions of EGF and IGF-1 receptors were detected by immunohistochemical staining in the 75 NPC samples and the 21 noncancerous samples. Furthermore, the messenger RNA and protein expressions were assessed by real-time quantitative polymerase chain reaction and the Western blot technique, respectively, in NPC cell lines and normal nasopharyngeal epithelial cells.
The 5-year survival rates, assessed by the Kaplan-Meier method, were 71.4% and 66.6% in the EGF and IGF-1 receptor protein-negative groups, respectively, whereas they were only 28.6% and 33.3% in the receptor protein-positive groups. The levels of these two proteins significantly correlated with each other, and the overexpression rates of EGF and IGF-1 receptors were 65.3% and 56% in nasopharyngeal samples, respectively. Furthermore, both protein expressions were significantly higher in NPC patients with cervical lymph node or distant metastasis than in NPC patients without lymph node or distant metastasis. Recurrence more often appears in cases positive for both proteins than in cases negative for both proteins. The expression levels of the receptor messenger RNA and proteins were higher in several NPC cell lines than in normal nasopharyngeal epithelial cells.
These findings demonstrate that both receptor proteins may play an important role in the invasion, metastasis, and recurrence of NPC. Both receptors are valuable markers for assessing the prognosis of NPC. Their expression at such high frequencies provides the basis of combined targeted therapy with specific pharmacologic inhibitors to enhance the effects of radiotherapy and chemotherapy.
表皮生长因子（EGF）和1型胰岛素样生长因子（IGF-1）受体在鼻咽癌（NPC）的生长和凋亡中起重要作用。它们分别被发现与NPC患者的预后相关。迄今为止，它们在NPC中的表达相关性及临床病理意义尚未得到专门研究。
1998年至2006年期间，在一家医院收集了75例NPC患者和21例非癌性鼻咽上皮样本。通过免疫组织化学染色检测75例NPC样本和21例非癌样本中EGF和IGF-1受体的表达。此外，分别采用实时定量聚合酶链反应和蛋白质印迹技术评估NPC细胞系和正常鼻咽上皮细胞中受体信使核糖核酸和蛋白质的表达。
采用Kaplan-Meier法评估，EGF和IGF-1受体蛋白阴性组的5年生存率分别为71.4%和66.6%，而受体蛋白阳性组仅为28.6%和33.3%。这两种蛋白的水平显著相关，鼻咽癌样本中EGF和IGF-1受体的过表达率分别为65.3%和56%。此外，有颈部淋巴结转移或远处转移的NPC患者中这两种蛋白的表达均显著高于无淋巴结转移或远处转移的NPC患者。两种蛋白均阳性的病例比两种蛋白均阴性的病例更易复发。几种NPC细胞系中受体信使核糖核酸和蛋白质的表达水平均高于正常鼻咽上皮细胞。
这些发现表明这两种受体蛋白可能在NPC的侵袭、转移和复发中起重要作用。这两种受体都是评估NPC预后的有价值标志物。它们如此高频率的表达为联合使用特异性药理抑制剂进行靶向治疗以增强放疗和化疗效果提供了依据。
