PD-L1蛋白在晚期肺腺癌中的表达及其与EGFR基因状态的关系

Expression of PD-L1 protein in advanced lung adenocarcinoma and its relationship with EGFR gene status

目的分析晚期肺腺癌程序性死亡配体1(PD-L1)蛋白的表达与表皮因子生长受体(EGFR)基因状态之间的关系。方法收集晚期肺腺癌患者的临床病理资料、EGFR基因状态及临床样本,使用免疫组化法检测PD-L1蛋白的表达,并其分期与临床病理特征、EGFR基因状态及表皮因子生长受体-酪氨酸激酶抑制剂(EGFR-TKI)一线治疗无疾病生存时间(PFS)之间的关系。结果 PD-L1蛋白在肿瘤细胞及肿瘤浸润免疫细胞表达的阳性率分别为78. 7%(48/61)、59. 0%(36/61),二者之间无统计学差异(P=0. 669); PD-L1蛋白表达与年龄、性别、吸烟史、组织类型、分化级别、EGFR基因状态均无显著相关(P> 0. 05);不同EGFR突变类型间PD-L1蛋白的表达水平亦无明显差异;一线EGFR-TKI治疗的PFS仅与EGFR突变类型(19del最佳,中位PFS 15. 0±1. 52个月,P <0. 0001)有关,而与肿瘤细胞PD-L1蛋白表达、肿瘤免疫细胞PD-L1蛋白表达、EGFR-TKI用药类型均无显著相关(P> 0. 05)。结论 PD-L1蛋白在晚期肺腺癌的肿瘤细胞及肿瘤浸润免疫细胞均有表达,但二者之间无差异,且与EGFR基因状态、EGFR-TKI疗效未见明显相关性。

Objective To analyze programmed death-ligand 1 （PD-L1） protein expression and its relationship with EGFR status in advanced lung adenocarcinoma. Methods 61 advanced lung adenocarcinoma patients were enrolled in this study. The clinical and pathological information, epithelial growth factor receptor （EGFR） gene status and tissue specimens were collected. The expression of PD-L1 protein was tested by immunohistochemistry, and its relationship with clinical and pathological characters, EGFR mutation, and progression free survival （PFS） of EG- FR-Urosine kinase inhibitor （EGFR-TKI） was analyzed. Results The expression rate of PD-L1 protein in tumor cells and tumor immune infiltrating cells were 78.7% （48/61）, 59.0% （ 36/61 ） respectively, whereas there was no significant difference between them （ P = 0. 669 ）. There were no correlation of PD-L1 expression with age, gender, smoking history, tissue Upes, differentiation grade, or EGFR gene status （P 〉 0. 05）. The difference of PD-L1 expression in different EGFR mutation point was not found. As the progress free survival （PFS） of EGFR-TKI firstline treatment in EGFR mutation patients, it only had relation with EGFR mutation Upes （P 〈 0. 0001 ）, but had no correlation with EGFR-TKI drugs and expression of PD-L1. Conclusion The expression of PD-L1 protein has no difference in tumor cells and tumor immune infiltrating cells of advanced lung adenocarcinoma. There is no correlation of PD-L1 expression with clinical characters and EGFR mutation, so as to EGFR-TKI fist-line efficiency.