免疫检查点分子PD-L1和B7-H4在卵巢癌组织中的表达及意义

Significance of the expression of immune checkpoint molecules PD-L1 and B7-H4 in ovarian cancer tissues

为探讨免疫检查点分子PD-L1和B7-H4在卵巢癌组织中的表达特点以及临床意义,收集46例手术切除的卵巢癌组织,通过免疫组化染色技术检测PD-L1和B7-H4分子的表达水平和定位,采用χ2检验分析其与样本临床参数之间的关系,Spearman法分析相关性。结果显示,PD-L1和B7-H4分子在卵巢癌组织内中/高表达所占百分比分别为67.4%(31/46)和82.6%(38/46),二者同时中/高表达率为58.7%(27/46)。膜PD-L1中/高表达与病理类型、分化程度有关(P<0.05),膜B7-H4中/高表达与病理类型有关(P<0.05);膜PD-L1与膜B7-H4的表达有相关性(r=0.553,P<0.05),浆PD-L1和浆B7-H4的表达有相关性(r=0.429,P<0.05)。该研究提示,卵巢癌组织中癌细胞膜表面PD-L1中/高表达提示肿瘤分化差,胞膜同时中/高表达PD-L1和B7-H4分子主要集中在卵巢透明细胞癌亚组,PD-L1与B7-H4在胞膜和胞浆的表达具有相关性,在免疫治疗卵巢癌时需考虑PD-L1和B7-H4抗体联合靶向干预。

This study aims to investigate the expression characteristics and clinical significance of immune checkpoint molecules PD-L1 and B7-H4 in ovarian cancer tissues.For this purpose,46 surgically resected ovarian cancer tissues were collected.The expression and localization of PD-L1 and B7-H4 were detected by immunohistochemical staining.The correlation with patients’clinical parameters was tested by Chi-Square and Spearman’s tests.The results showed that the percentage of medium/high expression of PD-L1 and B7-H4 were 67.4%(31/46)and 82.6%(38/46),respectively,in ovarian cancer tissues.The rate of samples with medium/high expressions of both PD-L1 and B7-H4 was 58.7%(27/46).The medium/high expression of cytomembrane PD-L1 was related to the pathological type and degree of tumor differentiation(P<0.05).A correlation was also observed between medium/high cytomembrane B7-H4 expression and pathological type(P<0.05).Cytomembrane PD-L1 expression was correlated with cytomembrane B7-H4 expression(r=0.553,P<0.05),and cytoplasm PD-L1 expression was correlated with cytoplasm B7-H4 expression(r=0.429,P<0.05).In summary,this study shows that the medium/high expression of cytomembrane PD-L1 in ovarian cancer tissues strongly indicates poor tumor differentiation.The medium/high expression of both PD-L1 and B7-H4 in the cytomembrane mainly occurs in ovarian clear cell carcinoma.The expressions of PD-L1 and B7-H4 in the membrane and cytoplasm are correlated.Therefore,combined targeted intervention of PD-L1 and B7-H4 may be considered in immunotherapy of ovarian cancer.