EphA2基因在脑星形胶质细胞瘤的表达

Relationship of EphA2 gene expression with pathologic grade proliferation and apoptosis of brain actrocytic tumors

目的检测EphA2基因在脑星形胶质细胞瘤中的表达并探讨其与星形胶质瘤病理分级、增殖和凋亡的关系。方法选取90例人脑星形胶质瘤标本，以逆转录聚合酶链反应检测EphA2 mRNA表达，以免疫组化法检测EphA2和Ki67蛋白表达，以TUNEL法检测凋亡，分别计算EphA2免疫反应评分（IRS）、增殖指数（PI）和凋亡指数（AI）并进行统计学分析。结果EphA2 mRNA和蛋白阳性表达率分别为47．8％和43．3％。EphA2IRS、PI及A1分别为（2．90±3．89）％、（30．42±24．91）％和（1．42±0．99）％，三者均随肿瘤病理级别增高而升高。EphA2阳性组PI明显高于阴性组PI，PI与EphA2IRS旱显著正相关；EphA2阳性组与阴性组之间AI差异无统计学意义，但AI与EphA2｜RS呈显著负相关。结论EphA2在脑星形胶质瘤巾高表达，其表达水平与肿瘤病理分级、增殖和捌亡密切相关，提示EphA2可能是参与脑星形胶质瘤恶性进展的重要分子。

Objective To investigate the expression of EphA2 gene and its relationship with pathologic grade, proliferation and apoptosis of brain astrocytie tumors. Method The expression of EphA2 mRNA in ninety cases of brain astrocytic tumors, also the expression of EphA2 and Ki67 protein was investigated by reverse transcription-polymerase chain reaction （RT-PCR） and immunohistoehemistry method, respectively. The immunoreaetivity score （IRS） of EphA2 and the proliferative index （PI） were counted. Apoptotic cells were screened by TdT-mediated dUTP-biotin nick end labeling （TUNEL） method, and the apoptotic index （AI） of brain astrocytic tumors was calculated. Results The positive percentage of EphA2 mRNA and protein were 47.8% and 43.3% respectively. The EphA2 IRS, PI and AI were （2.90 ± 3.89） % , （30.42 ± 24.91 ） % and （ 1.42 ± 0.99 ） % , respectively. All the above three values increased with the upgrade of pathologic grade of tumor. PI in EphA2 positive group was significantly higher than EphA2 negative group, and PI was positively correlated with EphA2 IRS. AI presented no significant difference between EphA2 positive group and negative group; However, AI was negatively correlated with EphA2 IRS. Conclusions EphA2 is overexpressed in brain astrocytic tumors, and its expression level is closely associated with the proliferation, apoptosis and pathologic grade of brain astrocytic tumors.