p53、CD117及CD44v5在胸腺上皮肿瘤中的表达及其意义

Expression and clinical value of p53, CD117 and CD44v5 in thymus epithelial tumor

目的 观察p53基因、干细胞因子受体（CD117）和白细胞分化抗原44变异体5（CD44v5）在胸腺上皮肿瘤组织中的表达,结合其WHO分型及Masaoka分期,探讨三者与其病理特征及预后的关系.方法 利用组织芯片技术,通过免疫组织化学法检测p53、CD117和CD44v5在104例不同类型及分期的胸腺上皮肿瘤、10例正常胸腺组织中的表达,将结果与肿瘤病理学特征及预后进行分析.结果 p53、CD117及CD44v5在胸腺上皮肿瘤中阳性表达率分别为38.2%、15.7%和57.8%,三者在在正常胸腺组织中无明显表达.p53、CD117和CD44v5在不同WHO分型间表达差异有统计学意义（P＜0.05）,p53和CD44v5在不同Masaoka分期间表达差异有统计学意义（P＜0.05）.CD117和CD44v5在胸腺癌中显著高表达,阳性表达率分别为60.0%和100.0%.多因素分析提示CD117的表达和Masaoka分期是影响患者预后的独立危险因素.结论 p53、CD117和CD44v5表达可协助明确胸腺上皮肿瘤分型,尤其检测CD117和CD44v5表达可辅助鉴别诊断胸腺癌与胸腺瘤.p53和CD44v5表达可反映胸腺上皮肿瘤的侵袭性.

Objective To investigate the expression of p53, CD117 and CD44v5 in thymus epithelial tumor and their correlation with clinicopathological features and prognosis of thymus epithelial tumor in combining with WHO classification and Masaoka stage. Methods The immunohistochemical expression of p53, CD117 and CD44v5 in tissues from 104 resected thymus epithelial tumors with different types and stages and 10 normal thymuses by tissue microarray. The correlation between the expression of the proteins and the clinicopathological features or prognosis was analyzed. Results Of 104 thymus epithelial tumors,38.2% were positive for p53, 15.7% positive for CD117 and 57.8% positive for CD44v5 respectively.All 10 normal thymuses were not positive for the three proteins. There was significant difference in the expression of p53, CD117 and CD44v5 p53 among WHO histological classifications （ P 〈 0. 05 ）. The expression of p53 and CD44v5 showed significant difference among Masaoka stages （P 〈 0. 05）. The positive expression rate of CD117 （60. 0%） and CD44v5 （ 100. 0% ） was significantly increased in thymic carcinoma. COX regression multivariate analysis indicated that the increased CD117 expression and Masaoka staging were significant independent prognostic factors. Conclusion p53, CD117 and CD44v5 are useful immunohistochemical markers for the diagnosis of thymus epithelial tumor, and the examination of CD117 and CD44v5 would greatly help in the differential diagnosis of thymic carcinoma from thymoma. The expression of p53 and CD44v5 in thymus epithelial tumor can predict its invasive capacity.