表皮生长因子受体活化与鼻咽癌患者无转移生存的关系

背景与目的:表皮生长因子受体(epidermal growth factor receptor,EGFR)在多种肿瘤中高表达,且与预后相关,然而,EGFR对鼻咽癌的预后价值尚存争议。本研究检测鼻咽癌组织中EGFR及其磷酸化形式(phosphorylated EGFR,pEGFR)的表达,探讨其与鼻咽癌预后的关系。方法:收集中山大学肿瘤防治中心1999年1月至12月住院治疗鼻咽癌患者的鼻咽癌组织110例,同时收集20例正常鼻咽组织。利用免疫组化方法检测鼻咽癌组织及正常鼻咽组织中EGFR及pEGFR的表达,半定量方法评价染色情况;采用单因素和多因素方法分析蛋白表达与临床病理特征及预后的关系。结果:EGFR及pEGFR在鼻咽癌组织和鼻咽正常组织的阳性率分别为100%(110/110)、10%(2/20)和60%(66/110)、15%(3/20),不同组织中两种蛋白表达的差异均具有统计学意义(P<0.001);EGFR蛋白高表达与T分期相关(P=0.034),而与其他临床病理特征无关。单因素分析显示pEGFR高表达患者5年无转移生存率显著低于pEGFR低表达患者(72.2%vs.91.0%,P=0.012),而多因素分析显示pEGFR表达不是鼻咽癌患者无转移生存的独立预后因素。结论:pEGFR高表达与鼻咽癌患者的无转移生存相关,EGFR活化可能与鼻咽癌的转移有关。

Correlation of epidermal growth factor receptor activation to metastasis-free survival of nasopharyngeal carcinoma patients

BACKGROUND & OBJECTIVE: Epidermal growth factor receptor (EGFR) is overexpressed in many tumors, and is correlated to poor prognosis. However, the prognostic value of EGFR expression in nasopharyngeal carcinoma (NPC) is controversial. This study was to investigate the expression of EGFR and its phosphorylated form (pEGFR) in NPC, and explore their correlations to the prognosis. METHODS: NPC samples were obtained from 110 NPC patients treated at Cancer Center of Sun Yat-sen University from Jan. 1999 to Dec. 1999. The expression of EGFR and pEGFR in 110 specimens of NPC and 20 specimens of normal nasopharyngeal tissues were detected by immunohistochemistry. The correlations of EGFR and pEGFR expression to clinical characteristics and prognosis of NPC were analyzed by univariate and multivariate analyses. RESULTS: The positive rates of EGFR and pEGFR were significantly higher in NPC than in normal tissues (100% vs. 10.0%, 60.0% vs. 15.0%, both P<0.001). High expression rate of EGFR was significantly higher in stage T3-4 tumors than in stage T1-2 tumors (63.6% vs. 43.2%, P=0.034), but it had no relationship with other clinical parameters. The 5-year metastasis-free survival rate was significantly lower in the patients with high pEGFR expression than in those with low pEGFR expression (72.2% vs. 91.0%, P=0.012). However, multivariate analysis revealed that pEGFR expression was not an independent prognostic factor for metastasis-free survival of NPC patients. CONCLUSION: Phosphorylation of EGFR is related with metastasis-free survival of NPC patients, suggesting an important role of activation of EGFR in the dissemination of NPC.